What is more efficient with a hydronic radiant floor heating system, a programmable or regular thermostat?

We just installed a radiant floor heating system and our plumber tells us that a regular thermostat is in fact more efficient than a programmable one, because it doesn’t have to use a lot of energy to get the water hot again. We installed a high efficient munchkin boiler. Thoughts?

4 Responses to “What is more efficient with a hydronic radiant floor heating system, a programmable or regular thermostat?”

  • WADE:

    I also have a munchkin boiler and radiant heat. I put programmable thermostats in just because I like the way they look and there is a off switch on them. I do not set them back. The best way is to set your temp and let it be. This is especially so if it is a heated slab. Have you considered a out door reset to change the boiler temp if it heats up out side. I haven’t put one on but it could help with the overheat in spring and fall.

  • Derek:

    I look at it like this..radiant heat is a nice even heat once its up and running. If you let your home go cool when your not home, a radiant system is going to have more recovery time than forced air. Any setback would be savings, but I dont think it would be substantial.

  • Wylie Coyote:

    When I built our last house we installed hot water heat radiant heat in the basement and the garages. Keeping them at 60 during the winter in the garage kept the cars from having ice. The programmable thermostat causes more problems than it helps. You will like the warm floor, and you can keep the temp a little lower and be comfortable.

  • Leo:

    It’s always more efficient to not heat, than to heat. (Except for conditions that would make a boiler cycle on and off very frequently.)

    That said, while using a setback thermostat with radiant heating can certainly save on fuel costs, it is often impractical. Whether it is practical or not depends upon the recovery time: How long does it take to bring the temperature back up after the house has cooled? With radiant systems this is often measured in hours, or even a full day. It’s not like a forced-air system that can re-warm a room in minutes.

    Depending on your home’s recovery time, you might be able to program your thermostat to anticipate your needs by hours. For example, if the house is empty from 8am to 5 pm, then have it begin heating again at 2 pm. You could also begin the setback well before 8am, since the thermal mass is already well loaded with heat.