By-Pass Sizing Calculator

Often with zoning systems a By-Pass is needed to relieve excess air when only a small zone or number of small zones cannot deliver the required air flow thru the HVAC System. A by-pass is often ducted back into the return air or into non-critical, common conditioned temperature areas such as entry ways, hallways, basements, etc.

Select your Maximum Total System Cubic Feet per Minute (CFM), then enter the CFM of your Smallest Zone to calculate the type of By-Pass Damper you require.

Note: If the By-Pass CFM amount is 30% or less of the Total System CFM, No By-Pass is required.

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SPRD08

The By-Pass Damper you are looking for is SPRD08.

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SPRD09

The By-Pass Damper you are looking for is SPRD09.

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SPRD10

The By-Pass Damper you are looking for is SPRD10.

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SPRD12

The By-Pass Damper you are looking for is SPRD12.

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SPRD14

The By-Pass Damper you are looking for is SPRD14.

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SPRD16

The By-Pass Damper you are looking for is SPRD16.

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RDM18-SPC

The By-Pass Damper you are looking for is RDM18 w/SPC.

Check it out here.

RDM20-SPC

The By-Pass Damper you are looking for is RDM20 w/SPC.

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ZDSM2020-SPC

The By-Pass Damper you are looking for is ZDSM2020 w/SPC.

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ZDSM2420-SPC

The By-Pass Damper you are looking for is ZDSM2420 w/SPC.

Check it out here.

ZDSM3024-SPC

The By-Pass Damper you are looking for is ZDSM3024 w/SPC.

Check it out here.

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