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Boiler controller for 2 stage boiler

OK. Thanks.


  • John_96
    John_96 Member Posts: 3
    Boiler controller for 2 stage boiler

    Hi Carol,
    We have a 300K BTU low mass boiler (gas fired) for our home (about 6000sf). (Lochinvar Efficiency +). It has a 2 stage gas valve (High fire and low fire).
    It seems to shortcycle, and someone had mentioned adding a boiler controller with outside temp sensor. They had mentioned Tekmar Controls. The specifics of our system are 5 zones (3 hydroair fancoils, 1 indirect Triangle tube water heater, and a radiant zone under the plywood of our bathroom subfloor). Our boiler must maintain an inlet temp of greater than 140 degrees or we will have problems with condensing.
    What would you recommend? Any paticular model? Thanks.
  • carol_3
    carol_3 Member Posts: 397
    Thanks for the question

    Gotta research this. I'll be back at ya soon.
  • carol_3
    carol_3 Member Posts: 397

    For outdoor reset, how about a Honeywell AQ475 for boiler control, or an AQ 675 for a mixing valve or an AQ775 for injection?
  • hydronicsmike
    hydronicsmike Member Posts: 855
    Sorry Carol...hope I dont bother you with this reply...

    ....but a single tekmar 374 Control would provide staging of the boiler stages and mixing for boiler protection in one.
  • carol_3
    carol_3 Member Posts: 397

    Glad to hear it. Thanks for the help!
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