On Nov 15, 5:38 pm, DerbyDad03 wrote:
On Nov 15, 1:13 pm, Mark wrote:





I have a York combination system with an oil fired furnace and a heat
pump. Everything is working fine but I have a question about how the
heat pump and furnace work together.

The thermostat is a 2 stage, when the first stage calls for heat, the
heat pump alone comes one. If the room temperature drops another
degree or so, the second stage calls for heat also and the furnace
then comes on. Here is where my question comes in. When the second
stage calls for heat and the furnace comes on, the heat pump
compressor still remains on. As the furnace heats up, the heat pump
condenser input air is getting hotter and hotter. The heat pump is
trying to heat air that has already been heated by the furnace. At
some point when the furnace warms up enough, the heat pump does
eventually shut off , but it seems that it is shutting off due to a
high pressure safety or something and that the line pressure is very
high at that point. I imagine I can hear the compressor straining to
pump heat into the already heated air and I'm thinking this can't be
good for the compressor.

Is it normal for a dual system to be designed so that the heat pump
and furnace both are operating at the same time or should the controls
be wired to turn the heat pump off immediately when the furnace comes
on for second stage?

thanks

Mark

Everything is working fine...

Based on the responses so far, perhaps that statement was a bit
premature. ;-)- Hide quoted text -

- Show quoted text -

well I've live din the house for 14 years and it has been fine..

I usually use the EM heat setting which is oil only, but with the
price of oil such as it is, I am starting to use the heat pump more
when it is above 30 deg F outside and I noticed this situation happens
occasionaly.

Mark