Installing a ductless heat pump system is easier than installing many other air-exchange heating systems. The most common ductless full-house heat pump is called a mini-split; installing a mini-split system can save you time and money, especially in retrofit additions to older homes that are heated by radiant steam or water panels.
Step 1 - Selecting a Heat Pump
Choose a heat pump based upon the size of your house, your budget and your climate. Full-house systems work better in colder climates than window systems, but they still cannot withstand long periods of subfreezing temperatures without wear, tear and eventual failure. You will need to determine the route for the conduit that will hold the refrigerant tubing, condensation drain, power cable and suction tubing. When ordering your ductless heat pump system, be sure to also order conduit of an appropriate length and size for your project.
Step 2 - Creating the Conduit
A 3 inch hole is required to run the conduit through the wall and connect the heat pump unit. If you are well aware of where your electrical and plumbing lines run, and the space between your indoor and outdoor heat pump components will be relatively small, you can easily complete this task yourself. This is another area where a ductless system stands out, as the security of having only a 3 inch conduit is much greater than that of having an in-wall or window heat pump, as it provides no easy access point to your home.
Step 3 - Installing the Outdoor Compressor Unit
There are 2 components to install for this project: the outdoor compressor/condenser, and the indoor unit. The compressor unit should be at least 10 inches from the wall of your house. Make sure that the connections are facing the wall, where the conduit runs. Keep the unit away from anything that might block its vents. The heat pump should be placed on a 3 to 6 inch slab of concrete, surrounded by gravel to ensure proper drainage.
Step 4 – Mount the Air Handler
Mount the indoor air handler. Another benefit of ductless systems is that this can be done on a wall, drop ceiling, or regular ceiling. For the sake of convenience, access and better drainage, the wall near your conduit is the best choice.
Step 5 – Connect the Units
Using 1/2 inch thick insulation, wrap the vapor gas line; this line runs through your conduit, and should be included in the manufacturer's diagram. Be certain you wrap the entire length of tubing. Cover the end to prevent anything from getting into the tubing. Connect the air handler to the compressor using the conduit. Make sure that no debris enters any of the connections. Make sure that all of your valve caps are sealed tightly, and that any pressure built up in the indoor coil is slowly and carefully released when the connection is made, to avoid any possibility of injury or damage. The units are now ready to be powered up.