Heat Pump Heating Systems:
Checking these heating systems is very similar to checking a forced hot air system. Heat pump systems are usually found in condos and warmer climate areas. Heat pumps can have an electric coil in the plenum area to assist these units in very cold weather. The electric coil is a backup heating element to warm the air in the ducts. This will help the unit to provide enough heat in very cold weather, such as, below 20 degrees Fahrenheit.
Do not test a heat pump in both the heating and the air-conditioning modes during an inspection. You can damage the compressor by doing this.
Do not test a heat pump in both the heating and the air-conditioning modes during an inspection. You can damage the compressor by doing this. When it's working properly in one mode, then the most important and costly parts are operating properly.
Check the exterior compressor unit while the heating mode is on. Look at the data plate to try to learn the age of the unit. The life expectancy of the compressor is about 7-10 years since they operate all year long in the heating and A/C modes. The life expectancy also depends upon the quality of the unit and maintenance given to the system. The compressor must be sitting on a sturdy, level foundation, like concrete. Uneven installations can cause premature failure of the compressor because it will be leaning to one side while the unit is running.
See if the compressor is making any unusual noises while it's operating. Check for an exterior service disconnect switch next to the compressor for emergency and repairs shut off. Make sure there's adequate ventilation around the compressor unit for the air intake and blower fan to operate properly. You have to prune all shrubs away and there should be no obstructions overhead. Check the coils for a buildup of leaves, twigs or dirt. Ask the owner or Realtor if the unit can heat the house or condo adequately in the cold months. Sometimes they can't in very cold weather.