Heat Pump Check list for inspecting

[Russel Ray]

Originally Posted by bking

Russell,
I never said the control box was connected to more than one system.
It is connected to more than one thermostat.

Other info just to help others:
A home with two or three hvac units usually does not have zoning.
The thing that indicates zoning are when there are more thermostats than hvac units.

I think we simply do it differently out here, as well as having different terminology. Our thermostats control our systems, so there would be one thermostat for each system here, and each system usually has one furnace and one cooling condenser. It is interesting in that I never find zoned systems without cooling condensers, yet, because of our weather, there are a great many houses that have no cooling system.

[Timothy J. Gardner]

Obviously HVAC zoning needs to be defined here so that all understand the term.

There are basically three different ways that zoning can be applied to a home. For example, a home could be zoned with equipment. This means you could have two - or more - completely separate comfort systems, each with an air conditioner, a furnace and a thermostat. One system might supply conditioned air to a downstairs area, while the other system handles the upstairs area.

Or a home could be zoned with controls and dampers, using a single comfort system. In this case, a home could be divided into as many as eight areas or "zones," with each zone having its own sensor that monitors the temperature and controls it with a motorized mechanical damper.

The third way is simply a combination of these two methods with two or more systems, each zoned with controls.

So, a home with two Heat Pumps, HVAC systems independantly controlled, has at minimum 2 zones.

FYI

TG

[Joe Funderburk, CMI]

What's the difference between aux.heat and emergency heat? I see some thermostats with both indicators.

Thanks.

[JLilly]

Aux heat supplements the heat pump (on at the same time). This is usually less than all the heat strips available. Emergency heat is strictly the alterative heat. It can be electric, gas or oil. It’s normally used when the heat pump is out of commission. There are exceptions to everything. Depends on the person wiring the unit up. I’ve seen units wired through outdoor t-stats that allowed all of the electric heat to come on with the heat pump if the temp was low enough.

[Russel Ray]

I usually see heat pumps in the higher altitudes here where it gets colder. So when one gets home at midnight, one can turn on the emergency heat and get the place heated much faster than just using the standard heating controls.

[Mark A. Timpani, CMI]

I don't think this post was mainly about zones. I think he wants info on inspecting heat pumps. Still some good zone info though.

[Mark A. Timpani, CMI]

Do you guys only test heat pumps on only a/c or heat? Like the ITA article states? They said one mode is enough.

[JLilly]

From my point of view one mode is not enough. I have to get out of my HVAC tech mode. A heat pump in A/C mode may work just fine but switch to heat mode and not function well at all. Defrost controls not functioning, stuck reversing valve etc. Wearing an inspector's hat you would not check these things. You would have to say due to ambient temperatures I was not able to check (heat or cool) and leave it at that.