Heat Pumps and Electric Heating - new home with heat pump

I am buying a house with a heat pump and a furnace. I have never dealt with a heat pump before, so I don't really know all the ins and outs of it. We asked the seller to replace the thermostat because it did not have the emergency heat setting that our inspector told us it needed, but the seller told us he wouldn't replace it because the heat pump and the furnace are not compatible and therefore the heat pump only functions as a cooling unit. This doesnt seem logical to me since they don't run together, the furnace is just there to kick in when its too cold for the heat pump to be effective. Is the seller giving us a line of bull, or does the furnace really need to be compatible with the heat pump for the system to work correctly? I haven't moved in yet, so I don't have specifics on the units. Any help anyone can give me would be great.

thanks
Kelly

kellym,
first, i want to welcome you to the diy forums, we try to help you take care of your stuff before you have to call a contractor, so we try to save you money, time, and effort. that being said, the description of the system indicates that the home has more than one energy source. be it gas, oil, or another source. most heat pumps are totally electric, let us know if there is another fuel source, and are you moving into a manfactured home? let us know,we will try to help

barry

Kelly, A heat pump has the ability to work in reverse. But that doesn't mean that you must reverse it. It can always run in the cooling mode without any adverse effects. Maybe your system is set up for gas furnace only in heat mode and the heat pump to run only in cooling mode. Nothing wrong with that.

Some heat pumps are "dual fuel". Which means the outdoor unit can heat the home until it gets too cold then the backup heat comes on. With a duel fuel set up this back up can be either gas or electric elements. I doesn't sound like yours is duel fuel but it could be.

Most do but not all heat pump thermostats have an emergency heat setting such as single stage heat pumps. Just goes to show you how much home inspectors actually know about hvac.

In the HVAC business "inspector" is a dirty word. I take it you are referring to a home inspector. In my experience home inspectors cause more problems than they prevent in the hvac area at least. If you really are interested in catching a major problem before it happens hire a professional. "Inspectors" typically don't carry credentials.

The main concern I have is the compatibility issue. If your indoor and outdoor sections aren't working together at peak efficiency it will just cost you extra on utilities and possibly even lead to breakdown.

Typically hvac systems (and even worse in new homes) have oversized equipment with undersized duct systems. Older systems ductwork is almost always leaky which lowers efficiency terribly. A system is only as good as its ductwork. Low air pressure is better than high and smooth path is better than a rough one for the air to carry your heat down. A poor duct system with sloppy air filter will ruin good equipment. Main problem is even a bad system will work, but it sure won't perform. Just like you can run on a treadmill with a sock in your mouth....but not for very long before collapsing.

The furnace is gas and the heat pump is electric. The reason I was asking was mainly because I was under the impression that the heat pump would be more efficient to run than the furnace for times when its just chilly, and that the furnace is needed for when its really cold. Am I wrong in that part of it? The home itself is over 50 years old (not manufactured, and it has a basement) , but the heat pump is about 6 or 7, and the furnace is just over a year old. And yes, I was referring to a home inspector in my description. So the main thing I'm wanting to know is, is there really a possible compatibility issue between the furnace and the heat pump that would prevent me from running the heat pump for heat? I know I shouldn't trust the home inspector to know everything, but I also don't trust the previous owner because frankly based on the way some other things are in the house I'd say he isn't the sharpest knife in the drawer. Unfortunatly I can't really afford to have someone out to look at it for me yet either, buying my first home has tended to drain the bank account a bit... :) so thats why I came looking here.

kellyM

I think it would be helpful if you provide the manufacturer, model, size, age of both heat pump and gas furnace.

If I understand the info you have provided, it seems you do have a dual fuel system but that it must be operated manually. By this I mean you the homeowner have to set the thermostat to operate either the heat pump or the gas furnace in heating mode rather than having a system that works seamlessly. This can be a real nuisance.

My suggestion is to discuss this directly with the selling party and have a clear understanding of exactly how the HVAC system operates both in heating and AC mode. I would want to verify that the gas furnace is operating correctly and the same with heat pump in both cooling and heating mode.

Unless the deal is sealed, I would forget this home. If that's not possible, then I would want to investigate why system is not compatible and what if anything can be done to make the system compatible other than purchasing a new heat pump or a new furnace. I find the statement about the thermostat as a red flag. You need to investigate further exactly what you have.

My opinion.

like Tiger says. Please post the model and serial number of the outdoor unit.

Are you sure it's a heat pump ??

I'm sure its a heat pump, it says it very obviously on the side. Also, I knew that having specifics would be helpful, but I don't know them because I haven't moved into the house yet. Frankly it will do me no good to try and discuss it with the seller because while he is a perfectly nice guy, like I said before he's not the smartest. He didn't even know he had a heat pump. Like Tigerdunes says, I'm trying to figure out if its just the thermostat that needs to be replaced, or if one of the units themselves would have to be replaced to be compatible. This isn't a do or die situation, I already know they each work independently, so I certainly won't be without heating and cooling. Also if I need to just wait until I get moved in and get all the specifics before I can ask again for help thats fine too. I was just wanting to get a feel for it at first.

kellym,
here is an interesting idea, why not bring a heating and air contractor/service company that has been recommended by friends and/or family, and have them look at the system? i mean, dang, if i was going to buy a used car, i certainly would take it to a mechanic to make sure everything was ok. the amount that you would have to pay them would be miniscule to what you would have to pay for in repairs. and if the sellers balk at that suggestion, i would walk from the deal.and please forget the "HE IS A NICE GUY" notion, he wants your $$$$$$$$ no if's ands or but"s about it. to use an old line "been there and done that". and remember a thermostadt doesn't the whole system make. what i am trying to say is make sure that you don't get into a money trap with your first and, not to mention a huge investment, home. please let us know how this all works out, we would like to know(we really care about our forum members).

barry

kellyM

Brent's suggestion is absolutely correct. It would be shortsighted not to know exactly what you have, how/if it works, and what are the operational methods/problems of this system. If you have the funds to buy a home, surely you can find the funds to have the HVAC system looked at.

My Opinion.

Like has been said get a good HVAC guy in to check it all out for you. if it is wired right now. the stat should turn on the heat or the cool for you. When the unit is on heat there should be a outdoor stat that will turn the heat pump on for you, then as it gets too cold out side for the heat pump to heat the home. The stat there will turn the unit over to the gas furnace for heat.

ED:thinker: