FAQ's
Questions you should ask about a new heating system
Regardless of the type of heating system you may be considering
for your home or business, there are specific questions you should ask the
dealer installer. These questions deal with finding out the actual efficiency
of the system, any operating limitations it may have, and the bottom line
of operating costs. The answers here are meant as a guide for what you should
try to find out with your questions.
Are the dealer and loop installers qualified?
Don't be afraid to ask for references from dealers. A
reputable dealer won't hesitate to give you names and numbers to call to
confirm his capabilities. The same with the loop installer.
How long is the payback period for your geothermal heat pump system?
To figure this accurately, you must know how much per
year you'll save in energy costs with a geothermal system and the difference
in costs between it and a conventional heating system and central air conditioner.
As an example: If you'll save $700 per year with a geothermal system and
the cost difference is $2,000, your payback will be less than three years.
If a home has ceiling cable heat or baseboard heat, do air ducts
need to be installed?
Not always. It may be desirable to install geothermal
heat pump room units. For some small homes, one room unit would provide
most of the heating and cooling needs. Ceiling cable or baseboard units
could then be used for supplemental heat.
Is the efficiency rating actual or just a manufacturer's average?
All types of heating and cooling systems have a rated
efficiency. Fossil fuel furnaces have a percentage efficiency rating. Natural
gas, propane and fuel oil furnaces have efficiency ratings based on laboratory
conditions. To get an accurate installed efficiency rating, factors such
as flue gas heat losses, cycling losses caused by over sizing, blower fan
electrical usage, etc., must be included. Geothermal heat pumps, as well
as all other types of heat pumps, have efficiencies rated according to their
coefficient of performance or COP. It's a scientific way of determining
how much energy the system produces versus how much it uses.
Most geothermal heat pump systems have COP's of 2.5 -
3.5. That means for every one unit of energy used to power the system; two
and one-half to three and one-half units are supplied as heat.
Where a fossil fuel furnace may be 50-90 percent efficient,
a geothermal heat pump is about 300 percent efficient. Some geothermal heat
pump manufacturers and electric utilities use computers to accurately determine
the operating efficiency of a system for your home.
What is the Btu size of the furnace that's being proposed?
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 know what size furnace you'll need,
you must have a heat loss/heat gain calculation done on your home. From
that, an accurate determination can be made on the size of the heating system
you'll need. Most fossil fuel furnaces are substantially oversized for home
heating requirements, resulting in increased operating costs.
Will open or closed-loop be best for you?
That depends on several factors, as stated earlier. A
dealer should be willing to install what's best for you, not for him.
Will the loop joints be heat fused?
The only acceptable method for joining sections of the
special pipe used for closed-loop systems is heat fusion. Any other method
will eventually result in failure of the loop.
Will the minimum entering water temperature have an affect on which
heat pump I buy?
Yes. If you have an open-loop system, your entering water
temperatures may range from the 70s in the southern United States to the
40s in Canada. All heat pumps can handle temperatures in the moderate to
warm ranges. A closed-loop system, on the other hand, will encounter EWT's
below freezing. Not all geothermal heat pumps will operate efficiently at
those temperatures. It's important for you to know what EWT's your heat
pump will handle.
