Installing a geothermal heat pump is a fairly substantial operation, but it can be done as a DIY project. On this page, you will learn every step you need to take for a successful installation. Everything you need can be sourced from this page, with all the different options available. The wonderful thing about a geothermal heat pump is that, once installed, it is low maintenance, and is a set-and-forget system.
1. Determine how you want to install the system
If you want to go the whole hard core DIY route and build and install your own geothermal heat pump, here is a full guide (176 pages) complete with video. This is obviously the cheapest, but as this is an untested system, you cannot guarantee the efficiencies.
If you want to buy a unit and carry out a DIY installation, there are links at the bottom of the page, where you can choose a horizontal or a vertical array, and order online. However, first go through steps 2 to 5 to determine what size system to get. I also recommend that you buy this downloadable e-book, which is a full installation guide, and includes everything that you need to consider.
You could buy the equipment yourself, and get a local HVAC technician to come and do the installation for you. This is often the most efficient way of installing, and will save you lots of time. You will have the full equipment guarantee from the manufacturer, and you will have an installation guarantee as well. Go through steps 2 to 5 below, and then click on the links below to see the different systems available to order.
Local contractors: you could get a local contractor to do everything for you, including supplying the equipment. Remember though, they get money for their labour, AND they will get a cut of the cost of the equipment (contractors also have to live!). You will save by buying your own. Just make sure you get the right sized system!
2. Determine the size of the system that you need
Be careful of going too small, or the system will not provide the heat you need, and you will use other energy sources to supplement your heat. This will eat into your energy savings. The size of your heating system is determined by two factors: the size of your house (how many cubic feet of house space do you need to heat?) and the climate zone in which you live. So, for example, in the middle states, with a typical house of 1700 sq.ft., you would probably use a 3.5 ton system.
Click on the link to go to an interactive size calculator to determine the size of system that you need
3. Determine the efficiency of the system you would like to buy
There are two measures to consider with any system you buy. You should consider the EER (Energy Efficiency Ratio) and the COP (Coefficient of Performance). Obviously, the more efficient your system, the better will be your long term savings. However, the initial payment will also be a bit higher. For geothermal energy, the COP is the more important figure to consider. You should aim for a minimum of 3.0. A mid range Daikin system (the most efficient that I have seen) has a COP of 4.3, which is really good. This means that, correctly installed, you get 4.3 units of heat for every unit of energy that you apply.
Click on the link to go to an interactive calculator that shows your typical monthly savings with an efficient geothermal heat pump.
Secondly, decide whether you need a Single Stage or Dual Stage heat pump. Single stage heat pumps use a single rate of transfer at all times during operation. However, dual stage geothermal heat pumps, also called a 2 stage, use two different rates of transfer. Put simply, these two stages are kind of like a “high” and a “low”. When the desired temperature and measured temperature are fairly close in number, the unit will not need to work as hard, thus using the “low” setting.
In this case, a low rate of transfer is all that is necessary for getting to the desired temperature, so there is no reason to use more energy than is necessary. Conversely, when the difference in temperature is high, and the unit needs to change the temperature several degrees quickly, the dual stage heat pump will switch over to the high rate of transfer and more energy will be used.
Dual stage geothermal heat pumps are more versatile and can potentially save money in the long run.
4. Determine which other equipment you would like install at the same time
You may wish to consider installing a solar water heater to use for your household hot water needs. This means that your ground pump will apply all of its output to heating your home. This is by far the most effective way of harnessing both ground and solar energy.
You may wish to install solar panels to provide the electricity to run your ground heat pump. Click here to see some options.
5. Decide whether you want horizontal loops of vertical loops
Either way, you are looking at a very disrupted garden!
A horizontal loop will draw heat from the surrounding soil, is somewhat variable over the season, and requires three trenches in your garden, about 4-6 feet deep. You will need a backhoe with a shovel width of at least 18”. You will need to determine the presence of existing underground pipes or cables. You will also need space to dump the earth that you dig up. Once the earth has been replaced, you will need to let it settle for a few weeks before you can relay grass, or you will need to roll the earth in layers as you replace it, in order to compress it.
You can order a complete geothermal heat pump system with all the parts, including the horizontal loop arrays by clicking here.
Here is a video of the installation process:
A vertical loop draws heat from the underlying geology, and so is thermally more consistent. It will require you to bring in a drilling rig, that will drill a borehole up to 200 feet down, into the rock layer. You then lower the pipes into the borehole, and seal the hole with a thermally efficient grout.
You can order a complete geothermal heat pump system with all the parts, including the vertical loop arrays by clicking here.
Here is a video of the installation process:
6. Apply for your tax credits
Here is a page with an interactive map which shows you state by state every incentive available to you, including the 30% federal tax rebate. Go ahead and apply for everything you can find, and reduce your costs considerably!