Variable Frequency Drives in Single Zone Rooftop HVAC Units as Installed by Commercial HVAC Contractors

It is our understanding that VFDs are now required in single zone units in California and that other states may follow. ASHRAE standard 90.1-2010 requires VFDs in single zone, direct expansion (DX) units with cooling capacities of greater than 9.1 tons. If you are not familiar with the term, DX units are your typical package rooftop units which have internal compressors. ASHRAE standard 18931-2009 also requires VFDs in single zone DX units with cooling capacities of greater than 9.1 tons and, in addition, two stages of cooling in units with cooling capacities of greater than 5.4 tons. This may provide additional savings because having multiple stages may allow you to use lower blower speeds than with single stage, on/off, compressors. You may check with your local code authority to see if these standards have been adopted by your jurisdiction, and/or consult with commercial HVAC specialists

As with any equipment modification, there are a few things you need to be aware of when having qualified commercial HVAC contractors install VFDs on single zone units. From the service contractors’ viewpoint, the most immediate issue is to ensure that the low-speed setting moves enough air across the coil in the cooling mode to prevent “flood back,” a condition where the refrigerant does not absorb enough heat and returns to the compressor in liquid form. In severe cases, flood back can damage even the newest scroll compressors. Concern for this may be the reason that both ASHRAE standards will accept a low setting of two-thirds of full speed. Since even slower speeds may work in many applications and provide greater savings, the safest approach would be to check each unit individually. Existing problems external to the unit such as undersized or restricted duct work, closed diffusers or dampers, leaks between the supply and return ducts and other issues may not allow for sufficient air flow when the blower speed is reduced. Insufficient air flow would also be a problem in the heating mode because it may result in the short cycling of the safety devices, overheating of the heat exchangers, and possibly an increase in the air temperature above the safe design temperature for that equipment.

http://altusmechanical.com/variable-frequency-drives-in-single-zone-rooftop-hvac-units-as-installed-by-commercial-hvac-contractors/

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Benefits of HVAC Maintenance for Businesses

The recent American cold wave has affected a lot of American cities. The record low temperatures and high levels of snowfall has affected education, services and transportation. The extreme weather reminded a lot of communities of the importance of heat in people’s lives.

Heat is usually provided to homes and buildings by furnaces and similar heating systems. Like a lot of other machines, however, furnaces tend to malfunction after a certain period of time. This is the reason why HVAC maintenance is required for both commercial and residential HVAC systems.

A reduced risk of HVAC failure when it is needed most is one of the greatest perks companies and families will receive out of regular HVAC maintenance. Businesses located in cold places cannot function properly if the heater malfunctions, which can cause these businesses to lose profits. A well-maintained heater prevents that unfortunate circumstance from happening.

Another positive that businesses can obtain from regular HVAC maintenance is a better heater. A regularly maintained heater can run much more efficiently, which means less expenditures for the company. A well-maintained heater can help businesses profit.

Thirdly, heater maintenance can have an effect on air quality. Dirty heaters equate to poor air quality that is detrimental to employees allergic to dust. Regular HVAC maintenance helps employees maintain good health and perform much better at work, which results in a better output for the company. 

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Air Conditioners for Human Comfort & Efficiency

Air conditioners are a must-have among many office spaces and commercial buildings. This is especially true of areas whose temperatures are too high for comfort.

An article on Bright Hub Engineering lists common sources of rising temperatures. The sun is the major cause of heat generation inside the room of an office or a building. Sun rays enter the room through the roof, walls, and windows of the building which results in the generation of heat within the room.

Other sources of generated heat are electrical and electronic appliances as well as the people themselves. If all these factors ‘work’ together in the same room, they can lead to highly uncomfortable levels of heat. As a result, air conditioning becomes a necessity to counteract these conditions.

The article also lists some of the advantages of an air-conditioned environment. According to research, people tends to tire faster in hot temperatures. Additionally, air that is free of dust can circulate inside the room and create a healthy atmosphere. Lastly, outside noise has virtually no way to enter an air-conditioned room because there is no need to open the windows.

All in all, air conditioners and other commercial HVAC systems can provide several benefits that contribute to human efficiency and inhibit the creation of an uncomfortable atmosphere.

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Design Guides for Commercial HVAC Systems Discussed at AEE/NCC Meeting

Recently, the Association of Energy Engineers National Capital Chapter (AEE/NCC) invited Dr. Paul Torcellini, the noted Group Manager for Commercial Building Research of the National Renewable Energy Laboratory (NREL), to speak at the Association’s monthly meeting. In his talk, Dr. Torcellini presented an introduction to the design guides the laboratory has published for various commercial buildings. Many of these are relevant to the business of designing energy-efficient commercial HVAC systems for Altus Corporation’s clients.

The guides Dr. Torcellini laid out detail design specifications for a wide variety of commercial buildings and cover requirements for 50% and 30% energy savings. The comprehensive list of buildings includes small and large hospitals and healthcare facilities, medium to big box retail establishments, small and medium office buildings, K-12 school buildings, small warehouses and self-storage facilities, and highway lodging, among others.

http://altusmechanical.com/design-guides-for-commercial-hvac-systems-discussed-at-aeencc-meeting/

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Commercial HVAC Services Provider Launches Newly Redesigned Website

Altus Corporation is proud to launch their newly redesigned website to improve the overall browsing experience of visitors when looking up their services. The company offers honest and reliable commercial HVAC repair and replacement options to customers in most of the Eastern United States, including New Jersey, Pennsylvania, Delaware, Virginia, and Maryland, among other states.

The website, redesigned by TripleE Fusion, now has a cleaner and fresher look that makes it easier for readers to learn more about the company. The overhaul starts with the updated logo that still uses the same red and gray colors but represents the movement of air in HVAC better and features a cleaner sans-serif font type. In every page, the banner now indicates the toll-free number and has a button that links to the contact page for immediate access to the company’s contact details.

http://altusmechanical.com/commercial-hvac-services-provider-launches-newly-redesigned-website/

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Tips for Energy-Efficient Commercial HVAC Systems

Climate change and improper use contribute to the risks and inefficiency of any commercial HVAC system. In addition, failure to conduct regular cleaning, tune-ups, or preventive maintenance results in costly repairs and, even worse, the need for replacement. Here are some pointers to help keep commercial HVAC systems fully functional and energy efficient.

Calculate your establishment’s energy needs to determine the most effective HVAC system. Decrease HVAC use by reducing lighting use, insulating windows, and sealing duct leaks. Install high-efficiency units with proper sizing, as well as take advantage of timers and fans.

Significant energy savings can be achieved when you enforce the use of your HVAC units only when and where necessary. Proper maintenance of not just the integral components but the entire unit can be the key to longevity and optimum efficiency.

Installation of an entirely new system may be necessary to cut energy costs. Carefully evaluate and compare the pros and cons of repairing and replacement. An experienced HVAC contractor can provide you with reasonable and cost-effective options.

Consult with reputable companies for more appropriate HVAC solutions and services that satisfy your needs. Invest in fully-functional and energy efficient commercial HVAC systems to ensure a pleasant, productive, and safe environment for your employees and customers.

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Improving the Energy Efficiency of HVAC Systems

Dr. Paul Torcellini, the Group Manager for Commercial Building Research of the National Renewable Energy Laboratory (NREL), spoke at a meeting of the Association of Energy Engineers National Capital Chapter (AEE/NCC) earlier this month. Among other things, Dr. Torcellini discussed the design guides published by the laboratory pertaining to commercial buildings. Many of these guides are relevant to the business of designing energy-efficient commercial HVAC systems for various users.

The guides Dr. Torcellini laid out detail design specifications for a wide array of commercial buildings and cover requirements for 50% and 30% energy savings. The comprehensive list of buildings includes small and large hospitals and healthcare facilities, medium to big box retail establishments, small and medium office buildings, K-12 school buildings, small warehouses and self-storage facilities, and highway lodgings, among others.

The design guides also lay out a step-by-step process for increasing net energy conservation toward the creation of commercial buildings that achieve net zero energy consumption—which basically means that the buildings are able to produce as much or more energy than they consume. This breakthrough is achieved by providing buildings with on-site energy generation capabilities using renewable energy sources. Such improvements, it is expected, will greatly enhance the efficiency of power-hungry HVAC systems.

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