Testing the Air Conditioning Systems

If the outside temperature has not been at least 60 degrees for the past 24 hours, an air conditioning system cannot be fully checked without possibly damaging the compressor.

In this situation, it is suggested that the present owner of the property warrant the operational status of the unit on a one-time start-up and cool-down basis when warmer weather allows. Internal conditions of condensing units and air handlers are not inspected: this type of inspection should be done only by licensed HVAC personnel.

Air Conditioning Compressors

An air conditioning compressor has a normal useful life of 8 to 15 years. Properly operating air conditioning systems will generally provide cooling differentials of 15° - 20°.  

Electric Furnaces

Electric furnaces have a normal useful life of 15 to 20 years, although at times the heating elements have to be replaced.

Oil and Gas Fired Furnaces

Oil and gas fired forced air furnaces have a normal useful life of 20 - 30 years. Many oil fired systems have been replaced with electric central heat and air systems. Old, unused buried oil tanks are often in poor condition and should be removed. If there is a possibility that an old tank is present, additional steps should be taken to confirm the presence or absence of the tank. This Report does not address underground systems or utilities but we will advise you if there are indications of buried oil tanks.

Homes equipped with gas furnaces, particularly if the furnaces are located inside the living space, should have carbon monoxide detectors installed at appropriate areas or locations to help alert the occupants if the system(s) malfunctions or if there is a gas leak.

Heat Exchangers

The heat exchanger in a gas or oil furnace is hidden from view; it cannot be examined nor its condition determined without being disassembled. Since this is not possible during a visual inspection, it is recommended that a service contract be placed on the unit and a service call made prior to settlement to check the condition of the heat exchanger.

Air Filters

Air filters should be changed or cleaned once every 30 - 60 days to provide proper operation of the system(s) and air circulation throughout the house.

Heat Pumps

Operation of the heating mode for heat pumps in warm weather (above 60 degrees) is limited to verifying that the reversing cycle activates. Extended operation of the heat mode for heat pumps in warm conditions can severely damage the equipment. Electrical back-up heaters for heat pumps generally can not be activated or verified unless the outside temperatures are below 50 degrees, and are not operated if the outside air temperature is above that level. Outside (condensing) units have a normal useful life expectancy of 8 to 10 years. Heat pumps need to be serviced at least once a year. The air flow is more critical than with other forced air systems; it is not advisable to shut off supply grilles to rooms except as required to balance heat and cooling flows. The filter should be kept clean, and interior doors should be high enough off the floor to allow adequate air flow under them.

Ducting

Ducting for central heat and air systems can collect dust or other contaminates, and it is advisable to have all ducting cleaned at least every ten years or so. Seams and joints of the ducting can sometimes dry out or break which will allow air loss; all ducting should be periodically checked and sealed if needed. The insulation wrap on all ducting should be properly maintained to prevent heat loss or transfer.