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Wife of Big Doofus
12-15-2007, 09:48 PM
If I leave the switch on Heatpump (45 degrees) & the outside temp falls below freezing, will the furnace automatically turn on? Or do I need to leave the furnace running? I will be leaving my unit for several days & it warms up in the day, but could get down in the 20's at night. I don't want to risk running out of propane while I'm gone.

rdunk
12-15-2007, 10:16 PM
We have two heat pumps, so we don't run the furnace very much. When the heat pump(s) are set to run, they will run, per the thermostat setting, until the outside temp reaches freezing (prox). At that point, the heat pumps shut off, and the furnace comes on automatically. I assume the reverse will happen, as the outside temperature begins to rise.

When this happened for us the first time, the noise of the furnace was startling, as we didn't know what was happening in the middle of the night. After looking in the data provided by Doubletree, we found this "furnace action" fully explained, so that made everything "ok". :lol:

jack_diane_freedom
12-16-2007, 09:19 AM
Ours works in exactly the same way. Set it and forget it. During the night the furnace comes on when below freezing and then in the morning when it warms up a bit the heat pump takes over again. Love it.

Wife of Big Doofus
12-17-2007, 05:15 PM
Thanks. It did exactly as you said. We had our heat pump set on 60 degrees and it stayed about 59 in the bedroom all night. The low outside was 19!

One more question - is it correct that while the heat pump or gas furnace is in operation, both are circulating warm air into the under compartment where all of the water lines are?

rdunk
12-17-2007, 08:33 PM
Quote: "One more question - is it correct that while the heat pump or gas furnace is in operation, both are circulating warm air into the under compartment where all of the water lines are?"
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Nope! The heat pumps operate in the same way as in the A/C mode, as far as air circulation is concerned. There is no conditioned air into the storage or lower equipment areas from the heat pumps. Air and return air vents are in the ceilings

On our 2005 RE, the furnace return air dumps down into the lower areas. So, when the temps are at freezing, or below, the furnace does need to be running to help keep water lines, etc. from freezing (hopefully).

sigo'suite
12-18-2007, 07:58 AM
Quote:On our 2005 RE, the furnace return air dumps down into the lower areas. So, when the temps are at freezing, or below, the furnace does need to be running to help keep water lines, etc. from freezing (hopefully).

Or an auxiliary heat source in the basement.

We keep a little electric heater set on the 500W setting and it kept the temp in the basement at 80 when temps dipped to 28 degrees. That was with heater on one side of basement and temp. monitor on other side of basement.

In this manner we can keep an electric heater in the living area and keep it comfortable without burning propane, as stated in another post on a similar thread.

Motor31
12-18-2007, 09:24 AM
There is another consideration regarding the AC and heat pump that is a potential fire hazard. I'll be posting more on it as soon as the replacement capacitor and motor starter come in. This is the 4th failure of this type we've had and according to the techs I've talked to, rather common to both Dometic and Coleman who use the same components. There is an after market system that is far more robust than the OEM components. I'll post pix, description as well as part ID on the upgrade.