supply damper

Paul S_3

In a job in NYC there is a Honeywell damper on the supply duct directly out of the air handler...why would that be there?....it doesn't look like a fire damper but I can be wrong....it feeds a main trunk that 2 other air handlers are tied into....thank you Paul S

Jamie Hall

Could it possibly

be to prevent back flow through that air handler if it is off and one or two of the others are on?  Or is it just on that one air handler?  Dunno...

Steve Whitbeck

YUP

What Jamie said. There to close off backward flow and loss of air if that air handler is shut down - as in staging.