6 signs of furnace trouble

Call in a professional if you suspect signs your furnace isn’t running like it should. (Photo by Rick Miller)

Call in a professional if you suspect signs your furnace isn’t running like it should. (Photo by Rick Miller)

Furnaces and other home heating equipment rarely fail at a convenient time. Knowing the signs of furnace trouble can help you call in a professional HVAC service company for repairs before the furnace quits completely.

1. The furnace runs constantly

If your furnace runs almost constantly, there could be a problem with the unit or the thermostat, or your home has a notably poor air seal. A furnace that cycles on and off too often, running for only a few minutes, should also be inspected and repaired by a professional.

Check the air filter to make sure that it’s not clogged, which can lead to poor furnace performance. You’ll also want to make sure the majority of room vents are in the open position. Closing too many vents can affect furnace operation.

If the vents and filter check out, call a professional to diagnose the problem. In many cases, a furnace may only need an adjustment or a tune-up, but the components inside the furnace can present a safety hazard for an unskilled homeowner.

2. No heat

It’s always a good idea to test your furnace early – before cold weather arrives and heat is a necessity. If your furnace isn’t producing any heat, check that all the corresponding circuit breakers and on-off switches are on before making a service all.

If your furnace has power, but you still have no heat, leave the repairs to a qualifeid professional HVAC company.

3. The furnace produces an odor

It’s normal to smell a dusty or musty odor when starting a furnace for the first time of the season, but if the smell continues, it’s a good idea to check and replace your air filter.  If you notice a burning odor when your furnace is operating, shut the system off and call for repairs. If you smell gas, leave the home immediately and call your local fire department.

4. The carbon monoxide detector goes off

If your home features gas appliances of any sort, a carbon monoxide detector is a safety item that’s a necessity. Carbon monoxide gas is odorless, tasteless and colorless byproduct from gas combustion that can be a lethal poison.

 If the detector alarm sounds, shut down all your gas appliances, open your windows and doors to introduce fresh air and leave the house. Have a professional HVAC company or plumber test all your gas appliances, including the furnace, to make sure they’re venting exhaust correctly.

5. Banging sounds when the furnace comes on

Most furnaces should be relatively quiet when they’re running. Banging or hammering noises can be common from radiator heat systems, but they shouldn’t be too loud. For forced-air furnaces, the sound of squealing or screeching when the furnace is running can indicate a blower motor in need of adjustment or repair. Loud pops, banging or grinding noises are strong signs of the need for immediate repairs.

6. Your utility bill suddenly increases

While you expect to see an increase in energy usage when the furnace is in operation during colder months, a sudden increase indicates a problem. If you notice a large spike in costs and the utility has not raised its rates, call for a service inspection.

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