a little help here please

[Hector Garza]

I am at an inspection at this very moment. Been doing this for ten years now and this is the first time I have ever seen a heating system that is both a gas furnace and a heat pump at the same time?! Flames are shooting out of the burners and the outside units are also running ("freon" lines are hot). What gives?! What do I tell my clients about this?

[Ron Bibler]

Break them down as they were 2 units. what do you find wrong with each unit. then advise you client.

As to 2 unit system that is very odd. I have never seen that before.

Are the 2 units by the same company ? If not let them known you need to do some Research

Best

Ron

[Jim Luttrall]

This used to be a common installation called "dual fuel" if memory serves me.
The only difference is you use a gas furnace instead of an electric for supplemental.
Sometimes there may be a manual switch so the client can choose the cheaper fuel to heat with, tends to take a little more involvement and understanding than the traditional straight electric system.
So long as the coil is down stream of the furnace to keep from rusting out the furnace during cooling, no problem with the installation in theory.
I would personally not want the gas furnace running at the same time as the outdoor unit since the head pressure will be very high and could damage the unit. I would rather see it set up to run in the "emergency" heat setting on the stat so that the outdoor unit is locked out when the indoor is running and vice-versa.
This can be a very advantageous set-up during fluctuating energy prices.

[Scott Patterson]

Sounds like a heat pump with a gas auxiliary or supplemental heat system. I see this type system from time to time.

The key is that when the gas furnace is on the outside condenser unit should be off. If both are running and it is automatic then a sensor is screwed up. If you select the Aux heat at the thermostat then and both are on then it is most likely at that thermostat.

Sounds like it needs service.