Hi I'm remodeling a house built in '32, with an addition in the 40s or 50s. The house is about 1200sq ft (800 sq ft w 9' ceilings, 400 sq ft with 8'ft ceilings) with a 1/2 basement where the heater (oil) water heater, circuit panel etc. At present there is no AC in this house, although the air handler has an evaporator in it. The oil furnace appears fairly new and was replaced prior to taking possession of the house. The heater has duct work 6 outlets and 4 returns with a single larger return above the air handler in the basement. All ducts are about 6" diameter.

The simplistic side tells me I should be able to add central AC (I suspect a 2ton unit would suffice for this size house) by installing a compressor/condenser outside, running the freon lines to the evaporator.

My question(s) is: Is there a way to converting this to a heat pump, and keeping the oil furnace as a backup (or alternate heat source when the weather is very cold)?

Is there a downside / upside to this?

Also, is there anyone that has experience using a geothermal heat pump with an injection well?

Thanks in advance to anyone/everyone's opinion.

Al

You can install a heat pump. The system will be called a dual fuel system. I recommend a pro look over your situation with the house for proper sizing and insulation/window factors. You should reall have a manual J done on the structure so you are not guessing as for size ETC.

hvac1000, Thanks for the information and advice.
My efforts will be to get the permits, run the electrical and the plumbing. I plan on contacting a pro, when getting to the details (sizing, location etc.) and to contract the hookup. I just want to make sure I ask the right questions and am able to explain what I want so I don't waste anyone's time and money.

As far as I know, you should be able to instal a heat pump or ad AC. Big difference is that a heap pump has reversing valves to direct the flow of liquid and vapor phases of the freon. The evaporator would also need to be capable of working as a condenser in the heating mode. What you already have may not do. You might see the heat pump section of the sticky at the top of the forum.

Most heat pump systems are set up to call on another source of heat below the temperatures where the heat pump is most efficient.

Geothermal heat pumps are very expensive. Even though they really slash your heating and cooling costs it would take forever to recoup those expenses. Also, is this in reference to THIS house (built in 1932)? If so, there are a lot of other options at your disposal to obtaining greater efficiency which would be a lot less expensive (adding insulation, sealing doors and windows, insulating hot water pipes, etc. etc.). Even one of the more expensive options, installing new windows, would probably be significantly cheaper and increase the value of your home. I would only go the geothermal route if they became significantly cheaper and I were building a new home in which I planned to live forever. :p

Airflow is very critical in a heat pump, ductwork, not the size of the house will be the priority. It can be done though. If you live in a very cold climate the cost of the heat pump may not be offset by the efficiency savings. Around here oil is still at a reasonable cost per BTU, at least better than LP.