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I am looking at installing a FHA propane furnace in series with my geothermal heat pump

Theoallen | Posted in Mechanicals on

I am looking at installing a FHA propane furnace in series with my geothermal heat pump so that I can remove the 20 kW electric backup and be able to install a generator. 1st, does this sound feasible? I see they are coming out with hybrid systems.

A relay on the emergency heat circuit would operate the damper and a limit switch would power the propane furnace thermostat when the damper was completely open.

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  1. GBA Editor
    Martin Holladay | | #1

    It sounds as if you want to be able to use a generator to provide emergency power during infrequent power outages, and your existing heating system (which includes electric resistance heating elements rated at 20 kW) draws too much current for most generators to handle.

    I would urge you to consider alternate solutions to your problem, including these:

    1. Install a wood stove for emergency use. During an emergency, you could turn off the circuit breaker to your heating system, to prevent your generator from being overloaded.

    2. Simply have an electrician install a switch that allows you to disable the electric resistance heating elements. During a power outage, you would have access to your ground-source heat pump (which would presumably not exceed the maximum current rating of your generator), which would keep your house from freezing (albeit without the occasionally helpful electric resistance heaters).

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