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120 vac fire damper, spring return/shut

3.9K views 5 replies 5 participants last post by  nik99  
#1 ·
Should 120 vac fire damper acuators have disconnects so a guy can service them?
 
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#3 ·
No. The most you can hope for is a rib relay, a manual reset high limit, and an on/off switch.

There's not really much to do to those things. If you have 120v present at the motor, and it's not opening, get a new actuator.
 
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#4 ·
Got that. Except for the on/off switch.

Every once in a while after a power outage a couple of dampers wont open. I was calling the on/off switch a disconnect. None of them have it. I was thinking about installing an on/off switch when I exercise the actuator. Usually just pulling the hot works.
 
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#5 ·
That type of damper is called a combination fire/smoke damper (fsd) as opposed to a curtain-type fire damper (fd). They "fail" to the default position of closed when not energized. If there is not a dedicated fire control panel, they should be wired directly into the air-handler fan circuit,controlled with a firestat or a duct smoke detector. You then kill the FSD power by disconnecting the AHU circuit for servicing.
 
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