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Switching Relays

MikeJMikeJ Member Posts: 103
installing in floor heat for all floors for a new house, used gypsum over pex for the main level and 2nd floor. I will have 5 pumps for the floors, one pump for air handler, one for indirect tank.
counting on not using air handler much,
any ideas for switching relays?
they have a huge shower 5-6 heads, not sure if I want to let the floor heat take over after a certain amount of time making hot water, 80 gallon tank.


  • ZmanZman Member Posts: 6,296
    What will the boiler be?
    What are the design temps, especially the fan coil?
    That is a lot af radiant pumps!
    Is the boiler piping installed?
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • MikeJMikeJ Member Posts: 103
    Boiler is a Lochinvar WHN155
    Fan coil temp around 160, fan coil should be use only for fast change in temperature to warm the house, or big swings and don't want to run the infloor, cool at night and warm during the day.
    Its a good size house, two stories with full basement, and two garages one garage on each side of the house. All has infloor,
    Its pipe up, pumps are coming in today going out there tomorrow to install them.

    I'm thinking of using a 6 pump panel for the infloor and air handler, making the air handler a priority.
    Then using the Lochinvar for the indirect and and installing a relay to isolated the panel until the indirect is satisfy.
  • ZmanZman Member Posts: 6,296
    The boiler will do domestic priority and can control the DHW circ. you just have to pipe it per boiler instructions.
    As for the rest of it, the in floor should never see anywhere near 160 degree water. I guess you could do as you suggest and make the fan coil a priority then wire it to a different temp curve on the boiler. Not exactly elegant.... The better way would be to install a mixing valve on the radiant and get the add on controller for the boiler to operate it.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • JUGHNEJUGHNE Member Posts: 7,861
    The "add on controller for the boiler to operate it", is that a Lochinvar item that is available or something else. Just curious as I have the same situation on one of my projects.
  • ZmanZman Member Posts: 6,296
    Lochinvar sells a mixing controller that will let the boiler control the valve. It is not cheap but is probably less expensive than going with a full blown controller like tekmar.
    "If you can't explain it simply, you don't understand it well enough"
    Albert Einstein
  • Gabriel@HBX[email protected] Member Posts: 9
    HBX makes a cost effective boiler control (CPU-0550) that will operate your mixing valve. If you want control over your pumps and radiant zones we also have a Zone Module (ZON-0500) that will tie in.
  • MikeJMikeJ Member Posts: 103
    Zman if you talking about the smart system mulit loop control, that is sweet. Never seen it before. Thanks, May use that one day.
    I have a caleffi ZSR coming should be able to get that to work the way I need

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