Results 1 to 5 of 5
  1. #1

    smoke detector shut down

    have 2= 7.5 ton 3 phase rheem split heat pump system and 2 = rheem 5 ton heat pump roof pack units 3 ph. that i need to have imediate swhut down, how do i do this on 3 ph. units, the 2 fan coils are indoors and are 3 ph, so have indoor smoke detectors and the other roof packs have outdoor smoke detectors mounted on the supply side of the plenums. need help...
    thanks gabe

  2. #2
    Join Date
    Mar 2009
    Several Miles from Sane
    Check with AHJ first but the easiest way is to simply run the "R" leg of your control (24VAC) circuit through the Open on Alarm contacts of the Smoke detector.

    How do you do it on Single Phase units ?
    If sense were so common everyone would have it !

    All opinions expressed are my own. Any advice provided is based on personal experience, generally accepted fact or publicly available information. As such, it is worth exactly what you paid for it, not a penny more not a penny less !!

  3. #3
    figured it out.... spliced into common wire from contactor, hooked to n/c and c on the smoke detector, from smoke detector to smoke detector wire in al1 and al2 this allows all smoke detectors to talk to each other, when one goes down they all go down

  4. #4
    Join Date
    Nov 2005
    Shreveport, Louisiana
    Good idea but you would be alot better to break "R" to the thermostat or control device. If you break the coomon on the fan and the control deivce is calling for heating or cooling you can cause equipment damage. Then it doesnt matter if its single or three phase
    UA Local 141

  5. #5
    Join Date
    Dec 2008
    sf bay area calif
    Have used the com between smokes before with pretty good results, may need to put an eol resistor on either end of the bus, depends on mfg. One problem is if the smokes are hard to get, you have to find the one that tripped to reset them all.

    To make life easier, most smoke mfg sell a small led reset setup, you can stick in a unit to show alarm status and reset remotely, pretty cheap too.

    I know its crude but I put the common from the xformer through the n/c smoke contact. On some units if you break 24v to t-stat the unit still may run the sf on an internal time delay, makes the fire marshal look at you real funny.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
Comfortech Show Promo Image

Related Forums

Plumbing Talks | Contractor Magazine
Forums | Electrical Construction & Maintenance (EC&M) Magazine
Comfortech365 Virtual Event