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Community and Q&A

Second Floor Heating (or lack there-of)

TPid | Posted in GBA Pro Help on

I live in a two story house with two furnaces.  One furnace is dedicated to the upper floor (bedrooms), and the second furnace heats the main floor and basement.  I am not currently using the second floor so the heat is off.  Now that the weather is getting colder (zone 6B), I am noticing cool air falling from the upper floor down the stairwell.   I have a few questions:

1) In order to prevent my main furnace from working too hard to compensate for the cold air falling down the stairs, can I create a temporary barrier at the top of the stairs?  I am wondering about something like putting a tension rod at the top of the stairs and draping a blanket over it to essentially create a fabric door.  Or maybe there is a more elegant solution?

2) I know I’ll need to turn the upper furnace on to prevent things from freezing, but what is a good temperature setting?

Thanks for considering my questions.

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  1. Expert Member
    NICK KEENAN | | #1

    I'm interested to see what other responses you get, who else wades in.

    Yes, keeping part of your house cooler will use less energy. Yes, some of that will be made up for with increased heat loss from the warm part of the house. As to your main furnace "working too hard," that is actually a good thing, long run times are good for HVAC equipment. Turning on and off is what kills motors. So long as you can maintain comfort the longer it runs the better.

    For upstairs, the big thing is keeping it warm enough that the pipes don't freeze. The thing to watch out for are spots that stay colder than the surrounding rooms, like pipes in an outside wall or even in an under-sink cabinet. Most HVAC equipment doesn't have thermostats that go below 55 or 50. For upstairs, I would set the thermostat at its lowest setting. Then I would try to provide separation so that the upstairs furnace is actually providing heat and not heat loss from downstairs. Initially most of the heat transfer is going to come from air movement, so anything you can do to partition off the air flow is good. It doesn't make much sense to do more insulation until the airflow is addressed.

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