I am building a new home. What type of heating source is the most "cost" efficient?
A gas furnace is more expensive to operate than an electric heat pump. How much more expensive will depend on the price of electricity and gas. Using recent APS (8 cents per kilowatt hour) and Southwest Gas prices (95 cents a therm), gas heating is about 50% more than an electric heat pump. The cost difference would be $80 - $100 a year for hearting a 2,000 square foot home. In addition, there is a monthly service charge of $8.50 ($102 per year) for gas.

You may have heard that gas is cheaper than electric. That is true if you only factor the cost for the energy content of the two fuels. At 95 cents a therm, gas costs $9.50 for 1,000,000 BTU (British Thermal Units). Electricity costs about 8 cents a kilowatt hour, which equates to $23.44 for the same amount of energy.

However, electric heat pumps have the advantage because they do not "create" heat by burning a fuel. Heat pumps "pump" heat by transferring it from the outside to the inside which makes them 300% efficient. Most gas furnaces are only 80% efficient. Heat pumps cost less to operate, even though the energy used to operate them costs more than gas.

Be sure to check with your local gas and electric providers for accurate prices. Your prices may differ.

Heat strips are the most expensive form of heat and are not generally recommended. However, apartments and less expensive homes tend to use heat strips because they are cheaper to install. They are also popular in vacation homes where heat is not used much, making the cost of installation more expensive than the operating cost.

If you were going to put in a new heating system at this time, what would be the most efficient fuel?
Electric heat pumps are by far the most efficient at altitudes up to 6,000 feet or so. They are less efficient in colder weather, but with the price of gas going up, they are competitive even at those altitudes.

Is it better to leave the heat pump fan running all the time, or should I set it on auto on and off?
If you want the most economical operation, set it on auto. If you want a stable, more even temperature and more comfort, set it on run.

Leaving the fan to run all the time mixes the air better and maintains a more even temperature throughout the house, but it costs more. If you can set the temperature up two degrees with the fan running all the time it's about a break even on the cost compared to running it on auto at two degrees cooler. If you have ceiling fans, you can get the same effect for less money by using them to distribute the air and running the air conditioner on auto.

Any recommendations on manufacturers or brands for replacing a heat pump?
It's more important to get a good contractor than it is to select a specific brand. There is very little data on relative performance among the different brands of air conditioners. The data that is available indicates there is not much difference between the major brands.

APS has a list of APS Qualified Contractors representing the best in the area. To get a referral for an APS Qualified Contractor, call (602) 371-3636 in the Phoenixarea, or (888) 890-9730.

When is the best time to have my cooling and heating systems checked? Do you have a list of recommended service people?
It is generally best to have your cooling and heating system checked in the spring, prior to the start of the heavy cooling season. If you have it checked before the cooling season starts, you can usually get more timely service and may also get a break on the price because spring is generally a slow time for air conditioning contractors. However, If your cooling and heating system doesn't seem to be working properly, or if it's making strange noises, have it checked immediately.

APS works with a group of independent businesses we refer to as APS Qualified Contractors. For a referral to an APS Qualified Contractor, call (602) 371-3636 in the Phoenix area, or (888) 890-9730 elsewhere.

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