Know Before You Buy
Don't be afraid to ask for references from dealers. A reputable dealer or loop installer won't hesitate to give you names and numbers to call to confirm his capabilities.
Split systems easily can be added to existing furnaces for those wishing to have a dual-fuel heating system. Dual-fuel systems use the heat pump as the main heating source and a fossil fuel furnace as a supplement in extremely cold weather if additional heat is needed.
Most units are easy to install, particularly when they replace another forced-air system. They can be installed in areas unsuitable for fossil fuel furnaces because there is no combustion, thus no need to vent exhaust gases. Ductwork must be installed in homes that don't have an existing air distribution system. The difficulty of installing ductwork will vary and should be assessed by a contractor. Another popular way to use geothermal technology is with in-floor radiant heating, in which hot water circulating through pipes under the floor heats the room.
In all probability, yes. Your installing contractor should be able to determine ductwork requirements and any minor modifications if needed.
Not always. It may be desirable to install geothermal heat pump room units. For some small homes, a one-room unit would handle the heating and cooling needs. Ceiling cable or baseboard units could be used for supplemental heat if desired.
Geothermal heat pumps don't use large amounts of resistance heat so your existing service may be adequate. Generally, a 200-amp service will have enough capacity and smaller amp services may be large enough in some cases. Your electric utility or contractor can determine your service needs.
Furnaces are designed to provide specific amounts of heat energy per hour. The term "BTUH" refers to how much heat can be produced by the unit in an hour. Before you can determine what size furnace you'll need, you must have a heat loss/heat gain calculation done on the structure. From that, an accurate determination can be made of the size of the system you'll need. Most fossil fuel furnaces are substantially oversized for heating requirements, resulting in increased operating cost and unpleasant temperature swings.
Your contractor should provide a heating and cooling load calculation (heat loss, heat gain) to guide your equipment selection. Geothermal heat pumps typically are sized to meet your cooling requirements. Depending on your heating needs, a geothermal heat pump will supply 80-100 percent of your design heating load. Sizing the heat pump to handle your entire heating needs may result in slightly lower heating costs, but the savings may not offset the added cost of the larger heat pump unit and larger loop installation. Also, an oversized unit can cause dehumidification problems in the cooling mode, resulting in a loss of summer comfort.
To figure this accurately, you must know how much you'll save each year in energy costs with a geothermal system as well as the price difference between it and an ordinary heating system and central air conditioner.
As an example: If you'll save $700 per year with a geothermal system and the price difference is $2,000, your payback will be less than three years. If you install a geothermal system in a new home, the monthly savings in operating costs generally will offset the additional monthly cost in the mortgage, resulting in an immediate positive cash flow.