Whether you're upgrading, replacing or installing your first HVAC system you will want to know as much as possible about the equipment and what you can expect from it. The following answers to frequently asked questions about commercial HVAC systems can help you understand some important basics about your investment in heating and cooling.
FREQUENTLY ASKED QUESTIONS
ANSWERS TO YOUR COMMERCIAL HVAC SYSTEM FAQ'S
What is HVAC ?
Heating, Ventilating, and Air Conditioning (HVAC) equipment perform heating and cooling system for residential, commercial or industrial buildings. The HVAC system may also be responsible for supplying clean indoor air to dislodge inside airborne contaminants such as to scents from natives, volatile organic compounds (VOC's) generated from inside furnishings, chemicals used for cleaning, etc.. A properly designed system will offer a comfortable indoor environment year-round when correctly maintained.
How does my Commercial HVAC work ?
An Air Conditioner cools and dehumidifies the air as is moves Over a cold coil surface. The indoor coil is an air-to-liquid heat exchanger with rows of tubes which pass the liquid through the coil. Finned surfaces attached to these tubes increase the total surface area of the cold surface, thereby increasing the heat transfer characteristics between the air passing across the coil and fluid passing through the coil. The kind of liquid used is based upon the system chosen. Direct-expansion (DX) gear uses refrigerant since the liquid medium. Chilled-water (CW) may also be utilized as a liquid medium.
When the required temperature of a heated water system is close to the freezing point of water, then freeze protection is added in the kind of glycols or salts. Regardless of the liquid medium used, the liquid is sent into the cooling coil at cold temperature. In the case of direct expansion equipment, the air passing over The indoor cooling coil heats the liquid refrigerant. Heat the refrigerant causes boiling and transforms the refrigerant out of a cold liquid into a gas. This warm gas (or vapor) is pumped out of the cooling coil into the compressor through a copper tube (suction line into the breaker ) where the warm gas is pressurized. Sometimes, an accumulator is put between the heating and the compressor to capture unused liquid refrigerant and guarantees that only vapor enters the breaker. The compression procedure increases the pressure of the refrigerant vapor and considerably raises the temperature of the vapor. The compressor pushes the vapor through another heat exchanger (outdoor condenser) where heat is rejected, and the hot gas is condensed to a warm high-pressure liquid. This warm high-pressure liquid is pumped through a smaller aluminum tubing (liquid line) to a filter (or filter/dryer) and then on to an expansion device where the high- pressure liquid is reduced into some cold, low-pressure liquid. The liquid enters the indoor cooling coil, and the procedure repeats.
As this liquid moves through the indoor cooling coil on the Inside the heat exchanger, two things occur into the air which passes over the coil surface on the outside of the heat exchanger. The air's temperature is reduced (sensible cooling) and moisture in the air is eliminated (latent cooling) when the indoor air dew point is higher than the temperature of the coil's surface. The total cooling (power ) of an AC system would be the amount of the sensible and latent cooling system. Many factors help determine the cooling capability of a DX air conditioner. Overall cooling is inversely proportional to the outdoor temperature. As the outside temperature increases the entire capacity is reduced. Air flow within the indoor cooling coil additionally impacts the coil's capacity and is directly proportional to the entire capacity of an AC system. As air flow increases, the entire capacity also increases. At higher air flow speeds, the latent capability of the cooling coil is reduced. Indoor humidity and temperature also affect the entire power of the AC system. As indoor temperatures increase, the practical capacity also increases.
Similarly, indoor relative humidity increases the latent capability of the AC system raises. Producers of AC equipment generally supply a"performance map" of particular equipment to demonstrate how total, sensible, and latent power change with changing indoor and outdoor temperatures and humidity. Power intake and energy efficiency are also provided in these graphs.
What type of AC systems has been Available ?
Cooling Only Split-System
A split system is a combination of an indoor air handling unit and An outside condensing unit. The indoor air-handling unit includes a supply air fan and also an air-to-refrigerant heat exchanger (or cooling ), along with the expansion device. The outside condensing unit is made up of compressor and a condenser coil. Split-systems are generally found in residential or small commercial structures. These programs have the highest energy efficiency rating (EER) of all the accessible AC systems. Manufacturers have to take the EER rating a step further and offer a seasonal energy efficiency rating (SEER) for use by customers. SEER ratings fluctuate widely and range from 10 to 20. The higher the SEER rating, the more effective the AC system operates. If heating is required, an alternate way of heating the inside of the building must be used, normally in the kind of electrical or gas heating.
Cooling Only Packaged-System
A packaged system is one unit combining all the components Described in the split system. Since the device is a bundle, it has to be placed outside the construction, and indoor air is "ducted" from the building to the packaged system and back through an air supply system. These units typically have SEER rating from 10 to 18. If heating is necessary, an alternate method of heating the interior of the building has to be used, usually in the kind of electric or gas heating.
Heat pumps are like cooling systems with a single exception. A special valve at the pipes piping permits the refrigeration cycle to be operated in reverse. A cooling only system cools the indoor atmosphere and rejects heat to the outside. A heat pump may also cool the indoor atmosphere, but when the valve is reversed, the indoor atmosphere is heated. A supplementary electrical resistance heater might also be used to assist the heating pump at lower outside temperatures. In colder climates, heat pumps need a defrost period. During defrost instances, the electric heater is the only means of heating the inside of this building. These components are manufactured as either split or packaged systems.
Chilled Water System
In a chilled water system, liquid water has been pumped throughout the Building to"chilled water coils." Since the liquid water has to be at a cold temperature, a "cooling plant" is demanded. The plant is typically known as a chiller plant. Vapor compression equipment in the plant, very similar to that described in"How can my AC work," cool water to a cold temperature and pump the cold water into air-to-water heat exchangers where needed.
Window Air Conditioners
As the name implies window air conditioner is typically Installed in a custom or window opening in a wall. The Window AC can only chill modest areas and are not meant to supply cooling to multiple zones or rooms. These air conditioners are fabricated as cool only or may offer both cooling and heating. An optional damper from the unit might offer clean indoor air if needed.
Packaged Terminal Heat Pump
Packaged terminal heat pumps (PTHP) are Comparable to a window-mounted air conditioner. These units are generally set up in a sleeve departure through the outside walls of an apartment, hotel, school classroom, etc.. PTHPs are self-contained and require only an electric connection in addition to the opening in the building shell. They use the outdoor air as the heat source in winter and as a heat sink in summer. They can also provide ventilation air. Flexibility and lower installed cost would be the primary benefits of the PTHP. Cons include in-room maintenance, greater operating cost, comparatively brief life, imprecise"on-off" temperature controller, and they may be somewhat noisy.
How is humidity controlled With an AC system ?
Humidity is becoming more of an issue to construction operators and owners. High indoor humidity contributes to mold and mildew growth inside the building. The are several ways of controlling indoor humidity. The simplest (and most expensive) way is to join a humidistat into an electric heater. After the humidity within the building rises above the humidistat set point, the heater is switched on. The further heat causes the air conditioning system to operate longer and remove moisture.
A more efficient method of controlling humidity would be to utilize the Waste heat from the refrigeration cycle itself. Rather than rejecting the waste heat outside, the heat is guided inside when humidity control is necessary. One form of heat reclaim is called hot-gas reheat or "refrigerant desuperheating" where the refrigerant is passed through a heat exchanger located downstream of the heating coil. The sexy high-pressure vapor leaving the compressor passes through this heat exchanger before entering the condenser coil. This, in turn, heats the indoor atmosphere and again causes the AC system to operate more time to fulfill with the thermostat set point. Even more, energy is used, this is much more efficient than turning on an electric heater. Another sort of heat reclaim is called sub-cool reheat. This strategy takes the liquid refrigerant in the condenser and passes it through a heat exchanger located downstream of the cooling coil. Less heat can be obtained using this method because the majority of the heat has been rejected in the condenser. Since more energy is used to pump liquid (as opposed to a gas) through the heat exchanger it might seem that this method is less efficient than the hot-gas method. However, the liquid in the heat exchanger is sub-cooled from the cold supply air stream which increases the energy of the air conditioner. Since more power is available, the AC units are able to meet with the thermostat more quickly.
Heat pipe heat exchangers or run-around coils perform a similar Work when humidity control is
required. Two heat exchanger is placed in the air stream, one upstream of the heating coil and another downstream of the cooling coil. These heat exchangers are connected with piping. A heat transfer fluid, whether it be water or refrigerant, is pumped or gravity fed from 1 heat exchanger to another. The heat exchanger down stream of the cooling coil (re-heat coil) cools the liquid medium within the heat exchanger and heats the air passing across the heat exchanger. The cold liquid in the heat exchanger is moved to the heat exchanger upstream of the heating coil (pre-cool coil) in which it pre-cools the air passing over the heat exchanger and warms the liquid passing through the heat exchanger. The impact of a heat pipe or run-around coil is to lessen the sensible heat capacity of the AC system. The latent ability of the AC system increases if direct-expansion equipment is used or remains relatively steady if chilled water equipment is utilized. Since the sensible capacity of the AC system was decreased, the system must run longer to fulfill with the thermostat set point, thereby removing more moisture.
How do refrigerants deplete the Ozone layer ?
Refrigerant 22 (R-22 or MonoChloroDiFlouroMethane, CHClF2) is one Of the most common refrigerants and can be employed in a wide variety of applications such as pipes, aerosol propellants, cleaning solvents, and foaming agents for plastics. This refrigerant is thought to be partially responsible for damaging the earth's ozone layer, and its usage has been phased out within the next two decades. The ozone layer is a consequence of sunlight reacting with oxygen to generate a layer in the stratosphere more than 10 kilometers above the earth's surface. As R-22 refrigerant escapes in an AC system through leaks or has been discharged into the atmosphere in other ways, the R-22 molecule containing the chlorine atom ("monochloro") increases in the air. Sunlight breaks down the R-22 molecule to yield a free chlorine radical (Cl-). The free chlorine radical combines with ozone (O3), decomposing it intonormal oxygen (O2).
AC refrigerants come in many forms. R-22 is the most common. However, due to interactions with an ozone layer R-22 has been phased out. Refrigerants manufactured as replacements for R-22 are HFC-134a, R-410a, R-410b to name a couple. The brand new refrigerants do not include the chlorine atom and aren't damaging to the planet's ozone layer.
Why does my heat pump Odor like it's burning off ?
Dust on the Electrical heater coil. Here is the most usual cause of a burning smell, particularly if it's the very first time you've switched in your heat pump for a long while or the very first time the auxiliary warmth kicks on due to dipping temperatures. ... You will odor this shortly after turning in your heat.
Is it OK to block a Heating vent ?
Blocking vent openings in 1 room will increase the Pressure of airflow to other chambers. Blocking too many vents can lessen the efficacy of your heating system or even shorten the life span of its components. What's more, inadequate airflow to a room can lead to moisture build-up, inviting mold, and mildew.
Is it harmful to Cover a vent ?
You can mess with The air stream. Simply because you cover the vent, it doesn't mean that your HVAC system understands that. It'll keep pushing atmosphere to all those vents, and when they are closed, you could make a buildup of air pressure and insufficient airflow which could harm your system.
How Can You unfreeze an Air conditioner ?
To thaw outside Your AC, you have to take two easy steps. First, switch your thermostat to OFF and your lover to ON. This will start defrosting your A-Coil, located inside your property. Give your device a couple of hours to completely defrost.
Why does my water Heater odor like its burning ?
It's possible that that the insulation may come Connected with the flame and lead to burning plastic or burning rubber smell. If you think this could be the offender, pull the bottom cover the water heater and check the burner region.
Is it OK to place Furniture over a port ?
It is improbable but not Impossible that obstructing a heating port and causing the furnace apparatus to overheat could make a fire. Place that the furniture over that the port in the summer, and you decrease the general airflow from a fundamental air-conditioning. Just how long does it take For the ice to melt on an air conditioner ? It can take everywhere Out of 1 hour to over 24 hours to unfreeze your air conditioner. It is all dependent on the extent of the ice buildup.
Why does my heater smell like burnt plastic ?
The most Frequent cause Of a burning plastic smell in your HVAC system is an electrical fault. A problem with link triggers the plastic coating onto the electrical cables to melt, making the burning plastic smell.
Is shutting vents bad for HVAC ?
Since closing Vents will lead to pressure to build up on your ducts, so your air conditioning unit or heater might have to work much harder to distribute the air properly. So not only is shutting a port counterproductive in terms of lowering energy use, but it is going to also create bigger and more expensive HVAC repairs as time passes.
How do I reduce my heating bill ?
10 Ways to Spend Less on Winter Heating Bills:
1. Utilize a lower thermostat setting. ...
2. Seal your chimney flue when not in use. ...
3. Use fans to circulate air. ...
4. Keep vents and radiators clear. ...
5. Clean vents, radiators, etc. ...
6. Look closely at your windows. ...
7. Close the doors. ...
Does final vents Damage furnace ?
Final atmosphere vents do not Just harm your furnace. Not maintaining all air vents open can additionally cause increased energy use. ... According to energy.gov, most homes already flow about 20-30% of conditioned air out of holes in air ducts.
Why does my water Heater odor like its burning ?
It's possible that the insulating material may come In contact with the fire and cause burning plastic or burning rubber odor. If you believe this could be the offender, pull the bottom cover off the water heater and check that the burner region. Whether you are Installing your initial HVAC system or upgrading or upgrading an existing one, you might want to know as much as possible about the gear and what you can expect from it. The following answers to frequently asked questions about commercial HVAC systems will be able to help you understand a few essential fundamentals about your investment in heating and cooling.
How Long Should My Commercial HVAC System Last ?
A Commercial HVAC system is going to require the investment of a few thousand dollars, and as soon as you invest that much cash, you want the equipment to continue as long as possible. Many things will influence the wellbeing of a commercial HVAC system, but on average, you can expect this kind of gear to last for 10 to 15 decades. By caring for the system with routine preventive maintenance and timely repairs, it is possible that a commercial furnace, air conditioner, heat pump, or boiler can last for 20 decades or longer.
Are High-Efficiency Systems Worth the Extra Investment ?
Heating And heating a commercial institution can be expensive. A high-efficiency commercial HVAC system can make a substantial difference in your monthly expenses. When compared with regular models, high-efficiency HVAC systems may slash heating and heating expenses by a considerable percentage. In many cases, system owners have noted the initial costs of a high-efficiency HVAC system could be retrieved through those monthly savings alone by about the halfway point of their system's anticipated useful lifespan.
How Often Should the Air Filters be Changed ?
Air Filters provide two important functions in a commercial environment. They help to clean your indoor air by trapping and holding particulates such as dust, pollen, fibers, and other material. Secondly, they contribute to sustaining the airflow that your HVAC system should function correctly. Dirty, clogged filters will block this airflow and stop your HVAC equipment from working properly. In the worst cases, dirty filters may even contribute to damage to the system.
In General, air filters must be checked every month and changed when they become dirty. If your commercial activities produce more particulates and airborne contaminants than normal, it will probably be necessary to check and change filters more often, perhaps even weekly.
How Often Should Preventive Maintenance be Performed ?
Preventive maintenance is just another element Of HVAC system care that will contribute substantially to gear function. Regular maintenance helps to ensure your commercial HVAC system will work at its finest for as long as possible. It simplifies the efficacy of your HVAC equipment and keeps those monthly savings you expect from a high-efficiency system. It will help prevent breakdowns and system malfunctions that could lead to expensive repairs or even complete system replacements. Telephone Your trusted local HVAC service provider for a preventive maintenance appointment at least once a year for each type of system. In general, it's best to have heating systems preserved in the autumn and heating systems in the spring. Since commercial HVAC systems operate harder than residential programs, it could be required to have maintenance performed more frequently than Consult with your HVAC expert for information.
How Much Attention Ought to Be Paid into the Ductwork ?
The Ductwork on your commercial HVAC system carries heated and cooled air to the Inside of your building. Considering that all of the conditioned air moves through the Ductwork, this system of pipes should also be inspected and maintained regularly. Air leaks in the ductwork can account for A considerable reduction of energy and money. To prevent these leaks, duct sections Must be kept in good repair and should be fitted closely together. Connections Should be sealed with mastic, a technical sealant for ducts, or with alloy tape.