Your heat pump thermostat helps to regulate the distribution of heat throughout your home. Installing a quality thermostat will save you money, time and problems down the road. This is a great DIY project, because of the relative simplicity of installation and wiring; you will not need an electrician, and you can complete the work with just one person.
Step 1 - Prepare to Install the Thermostat
The first step to installing your thermostat is to insure there is no power to the room, to avoid the risk of electric shock. Go to your breaker box and turn off power to the area of the house that you will be working in. Remove the old thermostat. Almost all thermostats have a cover and control panel that is easily removed; simply pop off the cover. If this doesn't work, check for screws or clips that may be holding the cover in place. Be careful not to damage the surrounding wall during removal. Label the wires on the wall once you have pulled off the cover. Do this by adhering a piece of masking tape to each wire and writing the wire information on it with a sharpie.
Step 2 - Exchange the Plates
Remove the old thermostat plate from where it is attached to the wall. Be careful with the wires; keep them securely pulled away from the wall so that they cannot drop back behind it, where they'll be difficult to access. The easiest way to solve this problem is to tape the wires to the wall to keep them in place. Use your screwdriver to carefully unscrew the old plate, and set it aside for disposal. It is now time to install the new thermostat plate. You will likely need to install new drywall anchors and drill several holes. Each model of thermostat will vary in its anchoring and screw hole patterns, based on age and manufacturer. Align the new plate to the wall, and mark the locations for the new anchors. Use your drill to create new anchors, but be careful to avoid the connecting wires. Screw the new plate onto the wall.
Step 3 - Connect the Thermostat
Once the new plate has been attached to the wall, you will need to attach the wires from your heat pump to the new thermostat. This is the most challenging step, as the wires may provide little leeway in the installation process. Once you have lined up the wires, remove the tape markers. Secure the wires to the new thermostat, and align the control panel and cover. Carefully close up the cover.
Step 4 - Using the Thermostat
Go back to your breaker box and restore power to the area. Referring to the manufacturer's instructions, program the thermostat. Choose setting that will provide the maximum comfort with the lowest possible heating bill. Try to keep the settings constant, as frequent alterations to your thermostat settings tax your heat pump and reduce the efficiency of your heating and cooling system.