Home Inspections - Heating and Air-Conditioning
Heating and Air Conditioning
Hopefully, you'll find this information helpful in maintaining your HVAC systems:
Furnace:
Owners of fossil-fueled furnaces (gas, oil, coal, wood) should purchase a maintenance contract that includes inspection of the heat exchanger as soon as they obtain possession of the home – especially if the furnace is more than five years old. Remember, that you must change the furnace filter frequently (approximately every three months). Owners of units that use natural gas should get their maintenance contract through their gas supplier (if available). Suppliers of natural gas typically do not sell furnaces and will not recommend replacing a safe unit just because a trace of gas had been found to get through the heat exchanger in a gas tracer test. Owners of units that use other fuels should get their contract through a trustworthy holder of a mechanical license. After the first year, a tune-up by a specialist is required every other year according to the Department of Energy.
Life Expectancy: Most furnaces last 20 to 30 years. Fossil-fueled, forced-air central heat furnaces cost $2,000 or more to replace. Floor and wall furnaces cost less to replace.
Ducts: Dirt in ducts of central heating systems may breed dust mites. Dust mites survive by ingesting human skin scales which abound in houses. Many persons suffer allergic reactions when they become sensitized to the dust mite's droppings. Ducts should be inspected once a year. Repair those with loose joints or holes that are losing expensive conditioned air to unfinished spaces. Consult a professional when cleaning metal or flexible ducts is necessary. If the insulation on flexible ducts has seperated, it should be repaired to not only avoid loss of conditioned air, but to prevent moisture from collecting in the ductwork which can present health concerns.
Warning: Do not operate an air conditioner when the temperature is below 65° F. or in the morning when the overnight low temperature is less than 55° F. Turning on a cold unit can cause liquid “slugging” of the compressor. Liquid (cold) refrigerant won’t compress and a compressor trying to compress it will self destruct.
Replacement: Remember that installation costs remain about the same whether good or cheap parts are used. Spend a little more to have a quality system. Always check out your contractor. If a compressor is found to be bad, the repair cost can be as high as $3,000. In rare circumstances, a small compressor may cost as little as $700.