Geothermal heat pump installation is the biggest HVAC project any homeowner can undertake. Not only are they just as complicated as regular heating and air units, but the earthwork adds, no pun intended, a whole new layer of potential problems.
Should you still install one? Is it going to be worth it? What don’t you know?
Geothermal Heat Pump Installation – What You Should Know
The first thing you should know is that there are two main geothermal heat pump installations available.
Closed loop systems rely on a literal closed pipe and refrigerant loop to move heat. They are by far the most common kind of geothermal unit. By contrast, open loops ground water or another body of water as the heat exchange medium. They’re relatively uncommon, since most homeowners do not have high enough quality groundwater or their municipal government does not allow unfiltered water discharge.
Is an open loop legal for your home? That’s really the big question you need to ask. If the answer is yes, then you can start checking water quality. If the answer is no, then it doesn’t matter what your local water table is like.
Provided an open loop is not verboten in your area, you will need a reliable amount of ground water or a large body of surface water to run an open loop geothermal heat pump. You also need to check local water quality. This can vary across different parts of the country. Ground water with a lot of contaminants will ruin a heat pump very quickly.
Now, if you do have legal access to high quality water, an open loop unit is the way to go. They can be a lot cheaper to install than closed loop systems. More importantly, open loop heat pumps tend to operate at much higher efficiency.
Open loop geothermal heat pump installation is great, but not an option for most homeowners. Chances are that you don’t have access to enough water, the water quality is too low, or your local government does not allow open discharge into ground water.
You’re not alone. The majority of geothermal heat pump installations in the United States are closed loop systems. Fortunately, a closed loop geothermal heat pump is still a great way to get high efficiency heating and cooling.
So, what do you need for a closed loop install?
You do have two basic options with a closed loop. You can go with a horizontal loop or a vertical loop. Both are pretty much what they sound like. A horizontal loop uses shallow, horizontal trenches over a relatively wide surface area. Vertical loops use deep, vertical trenches in a comparatively much more narrow surface area.
Which should you use?
It all comes down to the size of your yard. If you’ve got a lot of yard space, go with a horizontal installation. If you don’t, use a vertical loop.
Knowledge = Efficiency
And now you know what you don’t know.