What is the purpose of a bypass damper?

What is the purpose of a bypass damper?

The Bypass Damper is a pressure relief valve placed between the supply and return ducts of the forced air duct work. As Zone dampers start closing, the bypass damper will open and divert some of the supply air to the return.

What is return air damper?

Air Handler Return Dampers | HVAC Components – These return air dampers serve a large air handler on a rooftop. This return air damper ends up in a mixing box inside the air handler where the return air from the building mixes with the outside air from the economizer.

What does a face and bypass damper do?

Face/ bypass dampers typically modulate to force air to pass through the “face” of an AHU’s cooling coil or to “bypass” around them. In essence, the hotter the air is outside or coming back through the return air duct, the more we will want to “reset” the cold deck to a lower temperature.

What is a bypass vent?

A vent stack which runs parallel to a soil stack (or a waste stack) and is connected to it at frequent intervals.

How does a HVAC damper work?

HVAC dampers work by being situated closer to the mouth of the distribution pipe and will push or hold air from that point as needed. The pressure in the pipe will then redistribute the airflow to whatever zone requires regulating at that time.

How does AC damper work?

Do I need an air damper?

Yes, a range hood damper will help prevent leaves, small animals, other debris, and hot or cold air from entering your ductwork and home from outside; it will also prevent backdrafting, which occurs when the dirty, greasy air in your ductwork travels back into your home by way of gravity or air restriction.

What is a wing coil?

Wing IFB horizontal tube integral face and bypass coils offer the most effective preheat system ever developed. The IFB coil controls air temperature while full steam pressure or water flow is maintained in the coil at all times.

How is bypass damper calculated?

Use the following equation to help size bypass dampers for the correct airflow: Bypass Airflow (cfm) = Unit Airflow (cfm) – All Zones Minimum Airflow (cfm). To size the damper, select a damper based on calculated bypass cfm and a maximum velocity between 1,750 and 2,250 FPM.

How do Ahu face/bypass dampers work?

One very helpful method of accomplishing this balance is by effectively using “face/bypass” dampers. Face/ bypass dampers typically modulate to force air to pass through the “face” of an AHU’s cooling coil or to “bypass” around them.

Can outdoor air enter the AHU through the damper?

Member ASHRAE Member ASHRAE Traditional air-handling unit (AHU) control systems link the position of the exhaust, recircula­ tion, and outdoor air dampers. Laboratory tests of a variable-air-volume AHU using the tradi­ tional damper control approach revealed that outdoor air could enter the AHU through the exhaust air damper.

What is a bypass/faceface/bypass damp?

Face/ bypass dampers typically modulate to force air to pass through the “face” of an AHU’s cooling coil or to “bypass” around them. In some cases, there are both heating and cooling coils present and these dampers mix how much air passes through each coil.

How does the outdoor air damper control system work?

During occupied times, the outdoor air damper is fully open. Simulation results are presented that demonstrate that the new damper control system prevents air from entering the AHU through the exhaust air outlet for all but extreme conditions that are described in the paper.