Nevertheless, hot and poorly ventilated spaces are common in many older buildings where new "high-tech" tenants are occupants. Despite increases in office equipment use, however, office power on a gross-area basis does not usually exceed 2. 0 watts per square foot.

Though harmonic and power factor problems are not common in VSD applications, VSDs should generally be equipped with integral harmonic filters (or a three-phase AC line reactor) and internal power factor correction capacitors (or a single capacitor on the VSDs' main power line). Perform harmonic, power factor, electric load, and torsional analyses before selecting a VSD. In general, this equipment is not standard and must be specified.

There's one trend that's sure to make underfloor air distribution a viable alternative for a wider range of buildings in the near future: the progress being made in developing window glass that can regulate solar transmittance and heat rejection.

Oversizing the tower to allow for closer approach to ambient wetbulb temperature can improve its efficiency. Generously sizing the tower and increasing its share of the chiller load can make economic sense because a cooling tower's initial cost and energy use per ton are less than a chiller's. Cellular fill (aka film packing) increases efficiency over other fill types. Fill material, size and fan configurations affect cooling tower efficiency.

If the static pressure reading is less than the static pressure setpoint when inlets or dampers are open and VAV boxes open 100 percent, as on a hot summer day, the system is oversized. If a fan's inlet vanes or outlet dampers are closed more than 20 percent, it is oversized. If a motor's measured amperage is 25 percent less than its nameplate rating, it is oversized. Again, be sure to consider IAQ requirements when downsizing air handling systems. There are several ways to determine if VAV fan systems are oversized.

Installing a new pulley or adjusting the existing one can also be an alternative to a VSD when the cost for the VSD is prohibitive or the load has been reduced. Some energy-efficient motors have less "slip" than standard-efficiency motors, causing energy-efficient motors to run at slightly higher speeds; consider a larger pulley to compensate for the higher speed and to maximize energy savings.

Optimal start/stop enables the entire system to look ahead several hours and, relative to current conditions, make decisions about how to proceed; this allows the system to ramp up slowly, avoiding morning demand spikes or unnecessary run times.

(Sensors that monitor other contaminants, such as volatile organic compounds, are also available, though their relatively high cost has so far limited their use. The ability to know how much outside air should be brought into a space at any given time has been greatly enhanced by the refinement of low-cost electronic monitoring devices that accurately measure carbon dioxide levels.

Instead, the focus must be placed on applying those technologies that make the most sense in a given situation - and on simplifying and integrating systems. Given all the new alternatives, facility executives can't make decisions based on what's been done in the past. "Rules of thumb" provided a better road map when HVAC system goals and technology options were fewer and less complex than today.

Smaller units arranged in modular systems increase efficiency up to 85 percent while small units replacing those with open-loop condensing systems shoot combustion efficiency up to 95 percent. Especially in colder climates, improved boiler performance -- with improved fuel and airflow controls over a range of load conditions and increased heat transfer surface areas -- can contribute substantially to energy savings.

Having a master plan, defining clear long-range goals, and making sure that systems are as simple and integrated as possible is the most sound advice that can be offered as HVAC technologies and approaches to system design continue to change.

Installation problems related to fan control, reduced supply air distribution, location of pressure sensors and their reliability, in addition to deficient design, can diminish a VAV retrofit's performance. Careful zone designation -- according to occupancy, internal loads and solar gain -- will maximize efficiency, increase comfort and reduce reheat. Because VAV boxes are relatively expensive and one is required for each zone, it is generally not cost effective to partition the space into many zones. VAV retrofit costs and paybacks can vary widely.

An EMS can provide an abundance of information about building performance, but someone has to figure out what they want the EMS to do and then give it directions. Calibrating controls, testing and balancing are key to any well-maintained HVAC system, but are especially critical to optimize control efforts.

Air that arrives at an interior space at such a low temperature, however, cannot be released directly into the room. But if the cold air is combined with room air before it enters the space, it can be brought to an acceptable temperature - warm enough that the occupants below won't feel cold downdrafts. Dumping 46-48 F air into a room through a ceiling diffuser would likely cause some very real discomfort.But to maximize benefits and minimize capital investment, load-reducing measures, such as lighting upgrades, should precede HVAC system upgrades. HVAC upgrades can provide tremendous economic benefits, improve occupant comfort and system reliability, and reduce operating costs.

o complete load reduction measures and calculate the maximum and minimum air flow requirements,
o measure existing fan performance; examine duct system for possible improvements,
o stage fans that are in parallel configurations,
o commission the system thoroughly,
o optimize static pressure setpoint and implement reset control, and
o possibly remove return air fans.

In some cases, leaving enough space to accommodate future additions of equipment is a good approach for avoiding initial oversizing. Obviously, each project must be reviewed individually. However, monitoring actual building use provides a sound basis for establishing diversity in lieu of design-day calculations and guesswork on diversity values. Building owners can be of great help to engineers if they keep actual records of equipment use, calculate performance data and make this information available to the design community.

Systems with VSDs and several fans are more efficient when all tower cells are operating at reduced speed as opposed to one or two cells at full speed. At part-load conditions, applying a VSD to the fan (or pump) will improve the tower's efficiency.

Of course, it is crucial to maintain indoor air quality (IAQ) when altering air handling systems. VAVs respond to load requirements by varying the volume of the air through a combination of pressure controls and dampers rather than by varying the air's temperature. According to the air pressure, fan power and volume of conditioned air are reduced, thus increasing energy efficiency.

The place to start is with a close look at what is really transpiring in your building, 24 hours a day, seven days a week. Because a building's performance can be dramatically improved by installing and fully using HVAC controls, it is essential to understand and correctly use those controls.

Given this unpredictability, owners and developers of new facilities or those undergoing extensive renovations may wish to ask their consulting engineers to specify very high efficiency filters - as high as 85 percent efficiency - especially in some densely populated urban areas.

Using a combination of the two chiller types can reduce electrical demand charges. Absorption chillers cost up to $150 per ton more than vapor compression chillers like centrifugal units, but can be profitable in areas of high electrical demand charges or where steam or gas is available, depending on the local utility rate structures. Absorption chillers are an alternative to centrifugal models.

Today, the implementation of underfloor air systems is mostly limited to building interiors. In heavily glazed buildings, it has been necessary to supplement or replace underfloor air delivery at the perimeter with more conventional systems that are better able to handle the huge swings in temperature that can occur even over the course of a single day.

Chillers that have from 10 to 20 percent additional capacity allow chiller temperatures to be reduced by 1 to 2 F. This is more cost effective for meeting high-load periods than adding a chiller to serve infrequent peaks.

One approach to HVAC system design that emphasizes the "air side" has been receiving a great deal of attention lately: low-pressure underfloor air distribution. In this approach, cool air, which is kept at a slight positive pressure, is distributed through access-floor plenums and delivered to occupied spaces through diffusers set directly in floor tiles, from which it rises toward ceiling return vents through a natural convective process, removing heat and contaminants from the space as it travels upward.

That's especially true given rising prices and tightening supplies of CFC refrigerants. But once load-reducing efficiency upgrades have been completed, it may actually be profitable to replace an oversized chiller. No one wants to replace a perfectly good chiller just because of the CFC phaseout.

Demand-controlled ventilation can be incorporated into systems that mix fresh air with room air as well as into systems that have separate ducting for fresh air supply. Because installing an independent fresh air delivery system is fairly costly, however, the potential benefits of such a system must be carefully weighed against its substantial first costs.

With advances in lighting design, typical open workspace can be easily reduced to 0. Equipment loads, on the other hand, tend to be more difficult to estimate because of "diversity" - that is, the fact that patterns of actual use are constantly changing and that peak loads do not occur simultaneously throughout a facility. 0 watts per square foot. For typical office buildings, lighting and equipment are the largest components of cooling loads.This blending of chilled and room air can be accomplished by a fan-powered mixing box, set in the ceiling, that will produce a constant flow rate while varying the proportions of chilled and room air. Experience shows that if the blended supply air is within the 50-52 F range, it will mix well enough with room air near the ceiling (typically about 75 F) that no discomfort will result.

Over time, a business will develop a reputation based upon their customers' satisfaction. From there, it does not take long to go out of business. If the track record gets too much dissatisfaction, they will lose business.

Their business will grow until their company is virtually a household name. On the flip side, if a company has a long track record of customer satisfaction, then they are most likely going to last longer than other companies.

Moreover, this kind of system can be combined with low-temperature air to provide additional cooling capacity without a high-premium first cost. Variable air volume systems, which can deliver colder air if required but can be reset at a higher level when average conditions exist, are very efficient and allow for "built-in" capacity without much penalty on first cost.

Perhaps you might think that wearing clothing is just an opportunity to make a fashion statement! You too can turn the economic down-turn into an opportunity. Did you know that one of the attributes which separates human-kind from the rest of the animal kingdom is the ability to alter their environment? By preparing yourself to be a more viable employee in the heating, ventilation, and air-conditioning (HVAC) job market.

With the growing awareness of "sick home syndrome" and other problems that are related to your HVAC system, new technologies are being developed to address these problems. With the new generation of electronic air cleaners, UV lights and Ozonation, this is not much of a surprise.

Though evaporative coolers are particularly prevalent in the arid West and Southwest, they can service most U. E-Source states that, in combination with evaporative cooling, desiccant cooling can eliminate refrigerative air conditioning in many climates. Though initial cost is typically higher, paybacks for evaporative coolers range between six months and five years. Evaporative coolers provide one of the most economical and efficient means of cooling, using up to 75 percent less energy than vapor-compression systems.

Depending on the refrigerant and the way the retrofit is performed, the chiller may lose either efficiency or capacity. To determine whether replacement or retrofit is a better option, consider both initial and life-cycle costs. Retrofitting may entail gasket and seal replacement and motor rewinding.

Calculations of cooling needs using such a sum might easily exceed 2. The answer is no, for the simple reason that it's extremely improbable that that would ever happen. For example, sizing chillers for a hotel should not be based on the sum of the peaks of all rooms, public spaces, and back-of-the-house areas. 5 tons per room, including public areas. But the actual operating experience of hotels shows that total chiller sizing should be based on use in the range of 1. 5 tons per room including public and back-of-house areas.

A smaller "summer" boiler might be a good option when a boiler is required year round though at reduced capacities in warmer conditions. The much smaller summer boiler is sized for reduced loads; the main boiler is shut down. Boiler retrofits, combined with improved maintenance measures, can also increase efficiency -- up to 90 percent. New burners, baffle inserts, combustion controls, warm-weather controls, economizers, blowdown heat recovery and condensate return conversions provide increased efficiency opportunities.

In reality, there can be an enormous variation in the quality of outdoor air, depending on factors such as time of day and a facility's location. And it is difficult to predict how the general air quality at a location might change, for better or worse, over time. As useful as they are - and as crucial as they've proved to be in improving indoor air quality in facilities - the fresh air standards set by ASHRAE are bedeviled by one basic problem. The standards necessarily assume that the air being brought into a building is clean.

To improve performance consider lower air velocity; better fill materials; higher fan, pump and motor efficiencies, including VSDs; better belts or direct drive; improved housing; improved controls; and duct sealing. Hybrid systems that integrate evaporative cooling with conventional HVAC technologies offer additional opportunities. Proper maintenance is key to energy-efficiency.

In a tight market, with a lot of available space, that property may either have to reduce rent, offer concessions or decide to give tenants what they really want: An HVAC system that is flexible, usable, efficient and able to provide comfort and good indoor air quality for employees. In a landlord's market, a building with an outdated HVAC system may do all right.Thermal energy storage (TES) uses conventional chiller equipment to produce conditioned water or ice (or occasionally another phase-change material) in off-peak periods. Water is withdrawn from storage during the day or at peak hours and circulated through the cooling system.

If the speed is reduced by just 10 percent, a 27 percent drop in power consumption should result. The power to run the VSD is proportional to the cube of the speed (or flow), which is why this technology is so efficient. 5-year simple payback. A VSD pilot study performed by EPA found that VSD retrofits realized an annual average energy savings of 52 percent, an average demand savings of 27 percent and a 2.

In this case, replacement of selected components might be the best approach. It may also indicate that, although an HVAC system is 25 or more years old, overall operating costs may be comparable to newer buildings, so that a complete system replacement may not be warranted based on energy savings. Since high energy costs often justify HVAC upgrades, historical energy consumption should be compared against industry benchmarks of dollars or BTUs per square foot for similar types of facilities. This comparison will show how efficient a building is and will identify possible target values for improvement.

Smaller, more efficient motors are integral to a system downsizing stratagem; downsizing a 75 horsepower standard motor to a 40 horsepower energy-efficient model will result in energy savings of 15 percent.

If a facility contains a certain amount of heat-generating equipment, shouldn't the cooling system be built big enough to handle the load that would occur if all that equipment were running at once? It may be difficult to see the mistake that's being made when an air conditioning system is unnecessarily oversized.

Low operating costs, increased reliability and long life expectancies improve their viability. Heat pumps are among the most energy-efficient heating and cooling technologies available today. They function best in moderate climates and proper sizing is critical.

Building owners don't upgrade HVAC systems simply because they want the latest HVAC technologies; rather, they are looking to correct perceived shortcomings with existing systems. A detailed survey and inspection of all major system components should assess age, condition, efficiency and expected remaining useful life. That means the jumping off point should be a comprehensive assessment of the existing system. This should include a review of original construction drawings and maintenance and repair records. Performance testing or non-destructive testing may be warranted for major equipment components or systems, including piping and ductwork.

Savings of up to 70 percent can be achieved by installing VSDs on fan motors operating at part-load conditions. Backward-inclined and airfoiled fans are the best VSD candidates. They are also cost effective in water-side applications. They may be applied to compressor or pump motors and are generally used in variable air volume (VAV) systems. VSDs are profitable where equipment is oversized or frequently operates at part-load conditions.

o Is the ductwork and distribution system clean?
o How is the insulation attached? o Is sound batting provided? o What are the temperature setpoints of the zones? How many zones are in my space? o Can we control the perimeter zones of the offices separately? o What is the noise level of the terminals? o Is there any asbestos on the HVAC system, piping or ceiling? o What is the zoning per terminal? o How can I operate after hours and what is the cost per hour? o What are the watts per square foot and the cubic feet per minute of ventilation air? Please offer some verification. o If I want to add some additional servers, is there a tenant tower for condenser water? Is it interior or exterior fiberglass? o How will I be billed for use of my after-hour heating and cooling? o What am I guaranteed in the future?

Think about what extras, such as higher quality materials, are being offered. Is there an "odd man out" who gives a different diagnosis, but is cheaper than the rest? Thinking on this level is the best way to get the most for your money.

Tenants are often looking for space that can address such issues as flexibility, modular space planning, environmental considerations and individual temperature comfort. One way to identify tenant needs in existing buildings is to note what architects and designers are trying to create for clients in new buildings. A particular hot spot for many national tenants is to gain the highest level of productivity from their employees. The objective for a new building is to provide the ideal office space. This usually means the building will need plenty of HVAC zones, flexible office hours and point-of-use supplemental systems. These factors point to a flexible and often programmable HVAC system that can meet tenants' needs.

There are other building details that sophisticated tenants are aware of or will become aware of if they enlist a good tenant representative or broker. The potential tenant is concerned with the condition of the HVAC system and requests the following information: Consider a broker with a client that is considering an existing building over the brand-new building across the street.The more important the staff is to the operation, the more concern for the users' welfare. In the last few years, tenants have been even more concerned with the office IAQ (Indoor air quality) environment. Tenants are asking more questions like these:

Installing a self-contained, thermally powered device to each diffuser can add greater control to VAV systems by controlling individual spaces, rather than entire zones, and eliminate the need for VAV boxes. Such a device also offers VAV-style capabilities to CAV systems. Energy-efficient and properly sized motors are also recommended along with careful control strategies.

Some systems provide lower supply air and water temperatures, so air and water flow requirements can be cut. TES systems can be incorporated into new and existing systems and can provide partial load leveling or full load shifting. TES helps decrease operating and maintenance costs; in some cases, a smaller chiller can be specified.

Very often an energy payback exercise will show the project being way off the owner's target. If a property is competing with a state-of-the-art VAV building with lower operating costs and greater flexibility, where are the tenants most likely to go? This is when a facility executive must know the market. But the analysis must also take into account lease-up value, tenant retention, cash flow and ultimately overall asset value. Potential tenants may also want to see the property's preventive/predictive maintenance program, or to review the energy or computerized maintenance program to determine what occurs when the building operates outside its design parameters. Can the property afford not to retrofit?

An HVAC upgrade project is a significant business decision requiring a major capital investment. Given the magnitude of the financial impact and the long life of the equipment involved, it is advisable to seek the services of a qualified engineering professional to help guide the evaluation and planning process. The rationale for an upgrade may not always be direct savings in energy or operating costs, but may also include improved marketability or higher lease rates for rental property if the upgrade helps to reposition the property along with other functional and aesthetic renovations. Intangible considerations such as improved occupant comfort or higher occupant productivity should also be taken into account. The results of an engineering assessment may suggest that a complete system replacement or major upgrade is the best course of action but if an acceptable return on investment cannot be demonstrated to the owner, this approach will frequently not be approved.

Using heat pumps would require running condenser piping throughout the building and changing the fresh air distribution; what's more, the actual conversion could not run parallel to the old system if this retrofit was attempted in the summer because the cooling tower would be reused. Probably not if the building was configured as a constant-volume or multi-zone system. But is the first cost for installing heat pumps a good value for retrofits? For example, new speculative office buildings sometimes install heat pumps, which can deliver heating or cooling to small or large zones, are easily programmable, and operate at about 50 cents a ton per hour.

After the system assessment is completed, a key question is whether the major problems can be addressed by replacing components or if there are inherent limitations in the system that cannot be rectified without a major system renovation or replacement.

However, sometimes operations and maintenance requirements of a new system may require major changes in practices or personnel. Existing operating personnel may not have the skills to operate and maintain the new systems, or may not have the required licenses from the local jurisdiction. Even if the firm that worked on the original systems did a good job, it is important to verify that they have the skills and experience to maintain the new system. Operations and maintenance requirements will often be affected by HVAC upgrades. Usually, maintenance requirements will initially decrease when new systems are installed. This may necessitate some combination of training, hiring or outsourcing. Similar issues may arise for service contractors.

HVAC training classes are available either online, community college or through a trade school. One must undergo an apprenticeship which could last from 3-5 years. An HVAC Technician guide can be available in the internet and mostly they will tell you that HVAC certification matters if you need a job at this point where the present economy is experiencing a problem. A person with extensive HVAC training is highly qualified and will be an asset to a certain company. Sometimes, licensing may be required but that just depends on the laws of the area you are living in. HVAC training is important because the training can provide latest techniques on how to repair HVAC systems. As for the salary, an average HVAC technician can earn up to $40,000 per year and in other states, it could increase more up to $50,000-$60,000 per year.In today's ever-growing marketplace, there is continuous development of new HVAC (Heating, Ventilating, and Air Conditioning) technologies to increase the quality of life for us. To boot, modern buildings have life spans which equate to less than the life span of an individual. With the current need for energy efficient, healthy and comfortable indoor living environments, environmental and safety concerns, we need to rethink our approach to shelter. Sadly enough, the base necessity of shelter, which is the largest single investment that most of us will make in our lifetime, is still built and based on existing technology which is thousands of years old.

The existing water-cooled air-conditioning units on each floor were not sized to handle the quantities of outside air currently required. Consider one owner who was contemplating a major building renovation, including mechanical system upgrades. As a result, other system components, such as cooling towers and pumps, also had to be replaced. Although the equipment was in fair condition and could likely have continued to operate for several years, the owner elected to replace the units so the building would meet the new ventilation standard, as well as to avoid future disruption if replacement was required after the building was fully occupied.

Where reheat is used primarily to control humidity, a desiccant wheel or a heat pipe might be considered. When reheat cannot be eliminated, consider these steps to minimize it: ensuring thermostat calibration; increasing supply air temperatures during the cooling season; and monitoring reheat year round and possibly employing reheat only during winter months.

In addition, new systems may have capabilities that the older systems lack but that would enhance mechanical system operation and improve occupant comfort. Another consideration in evaluating an existing system is whether it uses an obsolete technology. Even with systems that are functioning reasonably well, it may be difficult to get parts or to find service personnel familiar with older technologies. Building automation systems have evolved considerably over the last 10 to 15 years.

In a medium or large-sized building, upgrade options will depend more on the type of system already in place. If the base building system is a constant volume system, with the main fans delivering varied air temperatures to large sectors of the building, there isn't much choice. How this is accomplished depends on the building's design and business plan. To serve the varied needs of today's tenants, the facility executive will need, at a minimum, to increase the zoning abilities.

When that happens - perhaps as soon as five years - it will no longer be necessary to install a separate system to handle the heating/cooling needs of the perimeter, and the overall short- and long-term costs of underfloor air systems will drop precipitously. New glass technologies that immensely improve the efficiency of the building envelope will likely be on the market within the next decade.

Fortunately, the technology which helps us maintain comfort progresses with time in order to help keep fuel and material costs reasonable. At the same time we keep an alert eye turned towards environmental safety factors. Of course, I'm being slightly facetious here, but it's because humans are so frail that we couldn't live just anywhere; most of the world is too hostile for us to live in without moderation. Are you up to date with the technological changes and industry codes?

Motors operate best when running at 75 to 100 percent of their fully rated load; motors routinely operating below 60 percent of rated capacity are prime candidates for retrofit. To achieve maximum savings, the motor must also be properly matched with its load, increasing run time at peak efficiency. For motors whose loads fluctuate, VSDs should also be considered.

Commercial HVAC equipment is too expensive and important to risk dealing with a contractor who does not put customers first. A contractor's record at the Better Business Bureau (BBB) can reveal things that you might not learn about from its references, such as whether it has a history of not resolving customer complaints. If the BBB record of a contractor shows unresolved complaints that are more than a month old, you should cross the contractor off your list.

Without insurance, a contractor does not offer compensation for injuries or property damage. Without bonding, a contractor does not offer compensation for stolen possessions. Without an HVAC license, a contractor is not permitted to perform HVAC work in the state of Georgia, and it may lack the knowledge to perform HVAC work at all.

It is important to analyze the existing system to determine whether the system is causing comfort problems. No one expected a system to provide a constant temperature year-round irrespective of outside conditions. Many HVAC systems installed in the 1950s and 1960s were only intended to provide a moderate degree of cooling.But systems that take advantage of diversity from space-to-space and floor-to-floor are usually effective at matching active loads without oversizing. Given this experience, convincing design engineers and owners not to oversize air-conditioning systems when designing for new construction is difficult. Fan-powered mixing boxes that vary primary air while keeping ventilation of the space high for good air quality are efficient devices. Air-based systems that can vary temperature in sequence provide the most flexibility.

Most employers are not going to take the time to filter through hundreds of applicants to judge experience and knowledge with on-site testing. There will probably always be opportunities for work; how you compete with other potential employees is up to you. The industry is not going away. For those who think a certificate of completion or graduation diploma is worthless, the plain fact is that the average graduate from centers of higher learning earns more money. People will sacrifice food before they give up their heating and air-conditioning. And now, due to layoffs and competition, it's imperative that the professional HVAC worker keep up to date and well trained. Most companies think many HVAC schools are of sufficient quality that the mere mention of their names evoke high regard.

You therefore use the common ducts 24 hours for 365 days. In the unfortunate event of failure, as is bound to happen, do not hesitate to call a specialized HVAC technician to identify and resolve the problems including replacement of parts, if necessary. Most units need a rest. This is a job for experts and you best leave it to an experienced and reputable company on a yearly maintenance contract, which would be mutually beneficial. The HVAC system runs cool air in summer and hot air in winter.

These days, heating repair services are more highly technical than they've ever been. When a heating system fails, there are many potential reasons that have to be sorted out with specialized equipment. Repairs are often equally as complicated, compared to what they used to be.

Homes built utilizing the new home system, are proven HVAC energy saving buildings, lowering heating and cooling costs substantially with shorter-term paybacks, a tighter building envelope, more efficient materials and a large thermal mass. In the end, this means that your furnace will only have to supply about half the heat output when compared to conventional framing. And when you include new home construction methods, energy required for space heating/cooling can save you as much as 78% on your yearly energy bills.

One of greatest drawbacks to older boilers is their poor electricity to heat conversion ratio, with some boilers operating at a shockingly low 40 percent conversion rate. As an example of how simply reducing the size of air distribution fans can lower your electric bill, consider that air distribution fans often account for 30 percent of a structure's electric usage. By retrofitting your HVAC system to accommodate an energy efficient boiler, the electricity to heat conversion ratio can raise by as much as 40 percent. Like older boilers, older chillers can represent a tremendous tax on your energy requirements, which stems from the fact that some chillers are "oversized" when compared to the structure that they cool. Similarly, air distribution fans can also be oversized, using far more energy than necessary to provide optimal climate control.

Fans operate continuously when spaces are occupied, but because less air is required to do the same job, energy costs also drop. When chilled air is distributed in the range of 46-48 F (as opposed to 55 F, the benchmark in conventional systems), less air is needed to cool interior spaces, so ductwork and piping can be significantly smaller than in conventional systems. That downsizing of air and water flow, in turn, means fans and pumps can be smaller.

Ultimately, the big question is how the estimate compares to other companies. Adding UV lamps to your system during an otherwise standard repair will cost extra. Naturally, a complete overhaul of your air system will cost you more than a simple refrigerant charging.

It consists of closed plastic cells that prevent air movement in or around the cellular structure. New constructions provide an air tight seal around the entire perimeter of the building, trapping your heat in. This consideration alone equates to a saving of approximately 42% of your heating/cooling requirements. Add ventilation requirements, humidity and the fact that heat rises, and you get a significant amount of outward pressure on the exterior insulated layer, much like a hot air balloon.

Perhaps some upgrades have been performed over the years, reducing the energy savings now available. But in many commercial office buildings it can be difficult to justify an HVAC upgrade. In some cases, the energy savings alone are so substantial that they justify the upgrade investment. Or perhaps the owner has a too short a payback-period requirement for energy upgrades. HVAC systems are major energy users, and new HVAC technology is far more efficient than 15 to 20-year-old systems in place in buildings.The reason is that the framed assemblies are losing out on the savings associated with thermal mass, lower air infiltration and conducted loss through the structural members. The Real R-values: You may have heard people talk about how the materials used in new constructions actually increase the thermal performance of the walls. As engineering studies have estimated, if you insulate a framed wall enough, you would have to fill the walls with fiberglass insulation, as well as install vapor and moisture barriers.

Reducing a fan's speed by 20 percent reduces its energy consumption by approximately 50 percent. o Make sure the fan's speed corresponds to the load.
o Rightsize motors and upgrade to energy-efficient models; install larger pulleys. o Reduce static pressure setpoint to meet actual temperature and airflow requirements. o Replace the existing fan pulley with a larger one; that will reduce the fan's power requirements by reducing its speed.

In the event a comprehensive system replacement is to be undertaken, compliance with the current codes will likely be required. HVAC upgrades must be carefully evaluated to determine the full extent of code-required upgrades; this work could make the project significantly more expensive than originally expected.

HVAC (heating, ventilating, and air conditioning) units are needed especially in those countries which are experiencing different seasons each year and an HVAC technician can be a rewarding job with great salary and greater chances of working anywhere in the world. This article will briefly discuss on the HVAC technician guide to give an idea on how the job can be a great field to work with. They need air conditioning units for comfort but they also need those units to be energy-efficient. Americans will willingly invest on their air conditioning units. But even purchasing units can bring some problems and only a professional can fix them.

One authority on energy issues, E-Source, reports that "typical (VAV) air flow requirements are only about 60 percent of full CAV flow. A common way to improve the efficiency of the air distribution system is to convert constant air volume (CAV) systems to VAV.

A four-year college does not necessarily prepare their students for the business world. The ability to read a book and test well on it does not make the person a good leader, a competent employee, or a problem-solver. People with these skills will have no trouble finding an HVAC job and succeeding in the future. A technical school will teach these skills though. You can be qualified for a stable and in-demand career with HVAC certification. Those who acquire their certificate are well-trained people who are able to work on a team, complete the task at hand, and foresee potential problems before they happen.

The earlier systems did provide easy zone creation; however, after-hour and flexible operation were usually not part of the operating system. If the building was constructed after 1975, it probably has some type of VAV system installed. VAV systems provide a constant temperature to the space, but the air volume varies with the comfort setting. In this case, options for conversion should be limited to a VAV conversion or to individual zone diffusing that does not reduce energy costs but does create comfort zones similar to VAV systems.

Some CFC refrigerants are still relatively widely available on a recycled basis; others are scarce or are very expensive. In 1996, the Clean Air Act mandated a ban on the manufacture of CFC (chlorofluorocarbon) refrigerants, which were used in virtually all large chillers produced up until the early '90s. An owner with a CFC chiller should consider refrigerant issues in deciding whether to replace the equipment. Environmental regulations may influence HVAC upgrades.

To receive your HVAC certification, students learn the technical equipment and the theory behind heating and air conditioning technology. In understanding how to troubleshoot problems, you will learn how one piece affects another, or in other words, how one problem can create another. Learning the equipment sounds like the easy part, right? Maintaining an HVAC system not only involves learning the physical parts of a unit, but how each part relates to another.

The following overview offers a quick reference to key considerations with some of the most effective technologies. As with lighting, trial installations are a good idea; so is working with manufacturers and distributors.

Replacement of an individual HVAC system component may not necessitate compliance with the new codes; however, this may be desirable to alleviate concerns that lower outside air quantities may lead to indoor air quality problems. Buildings built from the late '70s to the mid '80s were often designed to provide lower outside air quantities than required by current codes. Compliance with codes and regulations is another key issue.

A regular assessment schedule will throw wide open the problems with the system that could be outdated and not only sucking up your power and your bankroll, but also circulating bad quality air leading to health issues and Sick Building Syndrome. It is always mandatory to verify that your HVAC system follows an efficient operating system. It is better to invest on a new five star-rated system that would work efficiently with the least draw of power. Check up whether you have satisfied all statutory requirements with regard to environmental regulations, health and safety. Continuing maintenance problems with your HVAC system are sure symptoms of inefficiency that will lead to escalating running and maintenance bills, which you can ill afford.For example, over time, the percentage of outdoor air has gradually been increased, and current requirements may call for more outdoor air than many buildings have the capacity to condition. One factor that must be considered in any analysis of a possible retrofit is that an HVAC upgrade usually means that the building has to be brought into compliance with current codes. Bringing the building up to code may require a significant investment in upgrades beyond those originally planned. Some codes are based on prescriptive regulations; however, the trend to create a safer and healthier indoor environment can also bring new performance requirements.

Desiccants are dehumidification materials which can be integrated into HVAC systems to reduce cooling loads and increase chiller efficiency while improving indoor air quality and comfort. Formerly found only in niche and industrial applications, desiccant cooling is extending throughout commercial markets.

To begin your search, check the website of the Air Conditioning Contractors of America (ACCA) for a list of HVAC contractors in your area. If you need a contractor, the tips above should inform your selection process. Evaluating commercial HVAC contractors is a crucial part of hiring the right company for the job.

As the seasons change, do your operations change? Then it is imperative to ask, "What exactly do I want these controls to do? It is important to understand where and how energy is being consumed in order to identify where waste is occurring and where improvements can be implemented. What is happening with each piece of equipment?

The web is a place for other professionals to share their views on current economic trends affecting their profession. It's a place for professionals to get the word out about new equipment models and tools that will be useful in HVAC maintenance and repair. After HVAC technicians have completed their education at a heating and air conditioning school, they need to find other ways to keep up on the news and technologies that continue to develop within the industry. These things can be very useful to technicians in their every day work. Did you know that green building designs are affecting indoor air quality control and energy consumption by HVAC units? Schools do a great job posting articles in blogs to keep their graduates abreast of new ideas. Did you know that there has been a shortage in HVAC technicians recently? You would if you kept up with current blog postings.

But if your heating and cooling demands have remained the same, your bigger energy bills could be the result of faulty ductwork. Over the course of time, the connections between segments of ductwork can lose their seal and decrease the volume of forced air that is delivered to interior living spaces, meaning that some of the warm and cool air can get lost in ceilings and walls. If you find yourself with larger heating and cooling bills than in the past despite living in the same residence, you should first determine whether or not you use a higher level of heating and cooling than in the past. In most cases, variances in energy bills due to a hotter or cooler temperature setting result are minimal. But faulty ductwork can double or even triple a normal energy bill due to the fact that furnaces or boilers and chillers and air handlers are consistently working overtime.

Acing the test won't even make someone a great employee. The certificate though, is proof that a person is a well-trained technician, because certificates are only awarded to those people who have undergone and completed a series of training to successfully work with HVAC systems. An HVAC technician will not only have to study everything about the system.

Architectural trends can also create new loads and requirements for an HVAC system in an existing facility. If a building doesn't have a flexible HVAC plant, then modifications or upgrades to the HVAC system will be necessary to compete with new building design and technology. More natural light can increase heat loads; atrium designs can obstruct air distribution; additional zones can increase the overall volume of ventilated air needed, the quantity of heat to be rejected and the amount of outdoor air required.

For example, with replacement of a cooling tower dedicated to a central chilled water plant, it may be desirable to install additional capacity that can be utilized to serve individual tenant supplemental cooling equipment. Even with replacement of individual system components, future uses must be considered.

Unless the building is unoccupied, this may not be a realistic course of action. However, to accomplish this, the existing system must be carefully evaluated to reuse as much of it as possible, particularly within occupied spaces. A primary consideration prior to undertaking any building upgrades is the potential disruption to occupancy. Often, partial system replacements can be engineered and phased so that work is limited to unoccupied portions of a facility or only occurs during nights and weekends when the facility is not occupied. For HVAC systems, major upgrades may take some or all of the system out of service for an extended period.Noise concerns is another major concern that the Manual D duct system addresses. Noisy duct systems make everyone feel on edge or nervous. So finding the right materials and building the system in the right way is important to a successful project. You want to be sure you don't have unwanted noise in your home or office building that will interfere with the quality of life you have there.

If someone can show that he or she can step in and get to work without special attention for co-workers, that person is going to end up being a valuable asset to the company. Vocational schools all over the country provide students with the training to become such assets. Those who have studied HVAC technologies in school have learned the latest procedures and techniques to use in HVAC maintenance and repair. Why would it matter so much? Comprehensive training and an HVAC certificate will make you a very appealing candidate to an employer.

What really matters is if the HVAC company prices fairly for the service you will need, and if these repairs will hold up well over time. Price is a big factor for most of us when choosing air conditioning services. But customers should keep in mind that "cheap" or "expensive" can be relative terms when it comes to the quality of service you receive.

Installing VSDs on secondary pumps in variable flow systems, rightsizing pumps and motors to meet load requirements, and upgrading single loop systems to primary/secondary loop configurations can increase the performance and reliability of pumping systems. In upgrading chilled water pumps, it is important to meet maximum and minimum flow rates through the chiller.

Moreover, the manufacturers have used all the techniques under their control to improve the systems to run on minimum energy to provide optimum climate control at the sites that employ them. Now the more effective R410A gas has replaced the decades old R22 Freon gas. Over the years much evolution and advancement has gone into the HVAC technology. The unbridled escalation of power costs and the desire to trim down their carbon footprint is driving the manufacturers to embrace unique innovations to satisfy the customers and reduce their burden of contribution to the green gases to the minimum.

By properly selecting your HVAC system that consumes less power and is more efficient, and maintaining it regularly with experts on an annual maintenance contract, it would help you to run the system efficiently, reduce the contribution to green gases and considerably relieve you from large energy bills.

Some people add refrigeration to this abbreviation and call it HVACR. Using the principles of thermodynamics, heat transfer and fluid mechanics, the HVAC systems are a sub-division of mechanical engineering. HVAC, brief for heating, ventilation and air conditioning, provides atmospheric reprieve for household, office and vehicle interiors.

Every day, standards are being improved in the HVAC services industry. New technology is being developed, new and more effective materials are being released, and techniques are always getting more refined.

Those who complete the courses in a certificate program are more likely to be hired by an employer than those who have not completed a program. Earning your certification in heating and air conditioning prepares you for the rapid advancement of HVAC technologies. To become a qualified HVAC technician, it takes a technical understanding, leadership qualities, and problem-solving skills acquired through class studies toward a certificate.

The technology is quite complicated and to be an expert in it, you need to undergo rigorous training. You also need to understand why you need to hire an HVAC technician for installation, maintenance and repair. The complicated nature of the system is also the reason why technicians charge more than regular technicians. You would not want a less-than-qualified individual to handle your system though because he may do more damage than good.

Whether or not you are currently working, now is the best time to take advantage of HVAC retraining. Employees who strive to become well rounded in the HVAC industry through formal education will probably be in better shape to accept better jobs with greater responsibility and pay. Experience is one thing, and, although extremely useful, does not guarantee an adequate degree of technological knowledge. Employers will continue to look for well trained and otherwise viable workers to efficiently implement and maintain the latest HVAC technologies for clients who might be feeling the economic pinch. New HVAC systems are being designed all the time and older systems are continually updated as well. What employer isn't thrilled to see eager employees learn new skills and obtain the latest HVAC knowledge?

Increasing the outside air will increase heating and cooling loads, which the existing heating and cooling plant and related distribution systems may not have adequate capacity to serve. It is usually not as simple as rebalancing the air handling systems to provide additional outside air. A comprehensive HVAC system analysis is necessary to evaluate the impact of increasing the outside air rate.The marketing plan could then be changed to focus on larger, whole-floor users with large bullpen work areas that do not require multi-zone improvements. For instance, instead of converting a constant-volume system to variable-air-volume (VAV), it might be possible to make each floor a separate zone. It is best to start with the building profile. A relatively small or mid-sized building (less than 200,000 square feet) may present marketing opportunities not available to larger facilities. When energy savings alone do not clearly justify an upgrade, how does the facility executive responsible for a commercial office building determine whether and how to upgrade the HVAC system?

If the electrical distribution system consists of obsolete equipment that can not be expanded or if it does not meet current codes, significant additional upgrades to the electrical system may be required, at substantial cost. HVAC upgrades often have significant implications for other building systems. Changing the HVAC system will often require major electrical distribution modifications.

The HVAC systems also protects the inhabitants suffering from various health problems such as heat strokes, hypothermia, hyperpyrexia, excessive fatigue and more. Some of the HVAC equipment includes Air Handling Units, Condensing Units induced-draft types are more popular and efficient than forced-draft towers. Because cooling towers contain large heat exchange surfaces, fouling -- scale or slime build-up -- can be a problem. The efficiency of improperly treated systems can be improved with effective water treatment.

Ideally, replacement of heating equipment should occur during the cooling season and vice versa. Project schedules must also consider manufacturer lead times, which can be four months or longer for major equipment such as large chillers or boilers. Project planning should also consider seasonal heating and cooling requirements. If this is not possible, large central systems with multiple units serving a common load may be able to run most of the time with a portion of the units operational so that equipment can be replaced one unit at a time.

Whether you are someone who gets up at 6 am to spend time on the computer or likes to stay up until 2 am, you can participate in these communities when it is convenient for you. You can post your problem on a forum and see who responds. You don't have to go to a convention in another state in order to meet someone else in the HVAC industry to discuss a problem you've been encountering with a piece of equipment. Whether you live in Phoenix, Arizona or Anchorage, Alaska, you can participate in these communities. Time and place are no longer a factor in your ability to exchange information within your profession.

In fact, you could end up causing more damage if you try and repair the HVAC system on your own or let an amateur have a go at it. They Bring Experience to the Table - Air conditioning and heating equipment has gotten more complex over time, and there could be a wide range of possible causes for every issue. Unless you have the required training and experience, you're unlikely to be able to diagnose and fix it right.As an added benefit to having an HVAC specialist inspect your ductwork, the specialist can also determine whether or not your ductwork should be cleaned to improve indoor air quality. Regardless of whether you choose to implement energy efficient HVAC components in the name of long-term cost savings, it's important to remember that even small measures like repairing faulty ductwork can improve your indoor climate quality while reducing energy costs.

Whereas there are HVAC technicians that only specialize in a certain field, it isn't uncommon for an HVAC technician to be well balanced in all of the factors. HVAC technicians are required to install, maintain and sometimes design heating, ventilation, and air condition systems.

If you are looking for any employment opportunities in this industry, then it is essential to pass a competency test and receive the certification from the Environmental Protection Agency. Generally, the HVAC technicians work in all kinds of buildings such as large industrial plants, factories, private homes, etc. In order to operate the latest technology, the field technicians and contractors are appointed to install, repair and maintain the air conditioning systems.

The purpose of regular maintenance is to keep small systemic leaks, cracks, gaps, or slowdowns in check so that homeowners have the best, most energy-efficient, continuously performing HVAC systems possible. In vocational school, HVAC and mechanical maintenance engineers are trained to perform thorough inspections, to test systems in a proactive fashion, and to accurately and rapidly diagnose system malfunctions. Efficiency loss in an HVAC system is gradual, but pernicious.

The HVAC systems are considered to be the largest energy consumers in schools and other institutions. A good contractor will ensure to follow the procedures framed by the Air Conditioning Contractors of the particular country. Further, the technicians of HVAC have expertise in the areas of natural gas, kerosene heating systems, oil, propane and so on.

A major advantage to a systems approach is that it makes it possible to redesign and optimize the HVAC system. In an office building with a congested ceiling plenum - where additional space is needed for distribution of data cabling or new fire sprinkler systems - this may be a significant benefit. For example, a new HVAC system may be able to utilize smaller ductwork than that which presently exists. It may also be possible to design a new system to correct inherent comfort problems with an existing system, such as limited ability to control temperatures on a localized basis.

Those who work within the department, the instructors, and other HVAC professionals are available to students to guide them through the job application process, to make sure that the students' best skills are obvious to potential employers, and to ensure that students' skills are up to par for real world industry. A good vocational school will make sure that the transition between school and job placement is as smooth as it can possibly be for all students. Certification will make certain that students are prepared for just about anything a job could throw at them. Technical schools do not simply hand you a book to study, test you on the material, and then wish you luck in the business world. Employers will not want to take a risk in hiring someone who will not do the best work possible for them. Career placement departments are very helpful to students who have completed the certification process.

Clogged or dirty ducts or filters can hamper the efficiency of your HVAC system during cold weather. Prior to the arrival of cool weather, have your heating ducts cleaned -- and have your heating filter replaced regularly thereafter.

There are some things that must be done in a logical order. HVAC maintenance and repair techniques may have variations in it as well. Do you pour your coffee and then add sugar, or do you put the sugar in the cup and then pour the coffee? These variations in procedures can have varying results in the final products, although maybe not so much in coffee preparation. Other tasks, we are able perform in different ways. Online communities are great places to share your experiences and discuss successes and failures with other people. These exchanges of information based on experience with different HVAC technologies are incredibly useful in helping people do their jobs better. They may need a little help and guidance. Your method for completing tasks may be slightly different than another person's and therefore you have differing results. For example, you always put your pants on before your shoes. They may have better ways of doing things.

Heating, Ventilating and Air Conditioning (HVAC) systems help to regulate the climate and maintain the indoor air quality of homes and commercial buildings. While sophisticated and reliable HVAC systems have become common in daily modern life, they have not always been so widespread. Even though advances in the reliability and cost effectiveness of HVAC systems continue to improve, we enjoy very mature technology from this industry segment today. However, the principles that these systems operate on have long been known to scientists and engineers.Physical building constraints will almost always have a major influence on HVAC upgrades. This may have a significant impact on the functionality of the space or may reduce rental income. A new HVAC system may require more equipment room space or vertical shaft space for ductwork or piping, or may require additional space in other locations that must be taken away from occupied areas.

Online communities are great for today's business professionals. The web is no longer just a place for people to shop online or get the latest weather update, but a place for business professionals to exchange information and read about new technologies. Business owners and industry professionals who have undergone comprehensive training to excel in their careers can enhance their business strategies and stay up to date with current business trends simply by participating in online communities.

The tips below will help you avoid contractors that perform poor work and/or offer bad customer service: Although it seems as if all commercial heating and cooling companies would have the expertise and professionalism to do the job right, some of them do not. The quality of HVAC work depends on who performs it.

Places such as forums and blogs provide additional contributions to an organization's existing web site and places for professionals to connect with other professionals. It can mean an online organization to bring together in the form of industry societies or formal groups, but it doesn't have to be. They may be able to offer new ideas that you or the people you work with every day have not considered. These tools are great for people in the HVAC industry. What is an online community? A forum will allow a person to post a problem or question and get the opinions of other technicians in the field from all over the world.

A Manual D duct design gets very intricate with its sizing calculations. There are many different sizes and different kinds of ducts. Some systems are set up to handle constant volume and others need more flexible ducts. Some of them are VAV systems, both the multiple zone and the two-story ones. Manual D duct design techniques also teaches you about the potential problems and things that can go wrong with ducts. Likewise, you will learn in Manual D procedure about the enveloping equipment system and how to synch its performance with the overall duct system Sometimes duct leakage can lead to loss and that can adversely affect the indoor air quality in the building. There is also a system that has VAV dampers.

Air-to-air type heat pumps are the most common because of low up-front costs; ground supply heat pumps are the most efficient but tend to have higher initial costs. Multi-unit configurations can service larger loads and provide zoning; large, modernized central units offering capacities of up to 1000 horsepower or 750 kilowatts are gaining popularity.

In addition, the age of the building itself needs to be taken into account, as newer buildings have significantly better insulation with newer walls, and better performing windows. In addition to this, the energy