by High Performance HVAC | Commercial HVAC |
Variable Air Volume Box with Hot Water Reheat – The variable air volume box or VAV box is a commercial solution to adding multiple zones to large buildings. VAV boxes offer zoning solutions so that separate zoning demands or temperature selections can be maintained in different areas of the building.
If the president of the company wants the temperature in their office to be 70 degrees Fahrenheit but the vice president wants their office to be 74 degrees Fahrenheit then it is possible with the VAV zoning system as long as their VAV boxes are on different zones. (more…)
by High Performance HVAC | Boilers |
Boiler Circulator Pump: The boiler circulator pump induces the flow of hot water through the boiler and the boiler loop. Usually, the boiler circulator pump is controlled by the aquastat. However, there are various levels of control that can be found that control pumps.
One way is by the aquastat as mentioned above. Another way is an end switch in a zone valve. A thermostat in a particular zone will call for heat and the thermostat calls for the zone valve to open.
When the zone valve is fully open, an end switch closes the circuit to energize the circulator pump. Typically, the circuit is a control circuit so when the end switch closes it closes the circuit for a relay to energize the circulator pump (more…)
by High Performance HVAC | Commercial HVAC |
Heat Trace Tape Control for HVAC Piping - HVAC Piping systems, especially in the Northern regions, need a way to freeze protect piping the runs outdoor which is a necessity in many different HVAC application. To protect HVAC piping from freezing heat trace tape is wound around the pipe and controlled by an outdoor thermostat or temperature control that energizes the heat trace tape and keeps the pipe from freezing. (more…)
by High Performance HVAC | Thermostats |
Thermostat Selection Guide - This article will help you select the right type of thermostat for the HVAC system you have installed. It offers a comparison matrix for you to choose the right thermostat replacement. Get it right the first time!!!
So you have made a choice to replace the thermostat in your home or business and you decided to do it yourself. Hopefully, you will follow the advice on this website and read the instructions before replacing the thermostat.
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by High Performance HVAC | Boilers |
An outside boiler is prone to flooding
What Happens When My Boiler is Flooded - Richard, What Happens When My Boiler is Flooded? - Hurricane Irene was a disaster for us as we live in a Northern state that was hit by flooding from the rain of Hurricane Irene. As a result of the loss of power and the flooding, the basement was flooded.
Our boiler happens to be in the basement and we will soon need the heat. We have had a few contractors come by and look at the boiler with one contractor telling us we need to replace the boiler and another telling us we can rebuild the boiler. It is a little overwhelming given that winter is just around the corner and we need our heat. (more…)
by High Performance HVAC | Commercial HVAC |
VAV Air Handlers are ideal for providing zones in a commercial building. Office space typically has several offices and open areas that need to be conditioned for the comfort of the people working in those areas or offices. By installing VAV boxes and zoning the ductwork from those VAV boxes these areas and offices can be kept comfortable using a VAV air handler system. More on how VAV boxes work. (more…)
by High Performance HVAC | Air Handlers |
This MagicAire Air Handler serves as part of a large club and uses a DX (direct expansion) coil for cooling and a hot water coil in the air handler for heating. Many commercial air handlers are set up in this manner for heating and air conditioning. Hot water for the hot water coil is supplied from an oil boiler which supplies hot water to other air handling units in this building. In the center of the photo is the hot water coil and to the left, the line set which feeds the DX coil can be seen. (more…)
by High Performance HVAC | Boilers |
Old Bell Gossett Circulator Pump Bearing Assembly - This very old Bell Gossett Circulator pump and bearing assembly was found still functioning even after being flooded out several times in a basement. The pump, probably on its last leg, is at least 20 years old and still functioning.
It is unusual for an electric motor to continue to operate after being subjected to flooding. A circulator pump is comprised of an electric motor and a bearing assembly which holds the impeller. (more…)
by High Performance HVAC | Technical Reference |
Liquid to Vapor Propane Evaporators
These evaporators serve a large complex where natural gas is unavailable. The complex needed fuel for boilers for heating and domestic hot water so these evaporators were installed too along with two very large LP tanks to handle the heating needs of the complex. As liquid propane (LP) has a specific weight of .504 (where water is 1) and propane vapor has a specific gravity of 1.5 (where the air is 1) making propane vapor 1.5 times heavier than air. (more…)
by High Performance HVAC | Commercial HVAC |
Plate Heat Exchanger and Free Cooling - This plate heat exchanger is used in a data center for a chilled water system and is a chilled water economizer. Heat exchangers are used in marine applications, industrial processes including chemical processing systems, food processing, and many HVAC applications including chilled water applications, hot water applications, and economizer applications. (more…)
