Although many furnaces last longer than 10 years, this is the age at which certain components start to give out and furnace repairs become more common. If your furnace is approaching 10, then it's time to keep a closer eye on its condition. Here are five problems to be particularly on the lookout for.
1. Worn Bearings
The bearings in the blower motor sometimes start to give out around this age. The most easily recognized sign or worn or loose bearings is rattling noise when the blower fan is running. This might be most noticeable just as the fan turns off or when it is about to turn on. Replacing bearings is pretty simple, but you must have this done promptly so your blower motor does not experience additional damage as a result.
2. Broken and Frayed Belts
There is also a belt in your blower motor, and as the system ages, it can start to wear and fray. If the belt snaps completely, your system will stop blowing out air altogether. Thankfully, your belt should start making squeaking or squealing noises quite a while before it actually breaks. You may have to be near the furnace to actually hear them, so make a point of visiting your furnace while it's actually running now and then.
3. Cracked Heat Exchanger
This issue is a bit more serious than the other problems on this list since it can lead to carbon monoxide leaks in your home. The heat exchanger, which isolates the circulating air from the burning fuel, can develop cracks, allowing CO to circulate in your home. Signs of a cracked heat exchanger include a booming noise when the heat kicks on and an odor that resembles that of formaldehyde. This is an expensive problem to fix and often warrants replacing the furnace.
4. Faulty Thermostat Wiring
The wires that lead from your furnace to the thermostat can sometimes become frayed or worn. If the furnace stops turning on or starts short-cycling -- turning on and off again in short succession -- this is a problem to look into. A few new wires, and everything can be up and running again.
5. Dirty Burners
If you do not change your air filters several times per year, dirt may accumulate on the burner. Your furnace may then make a "bang" noise when it turns on. Dirty burners really reduce your furnace's efficiency, so it's a good idea to have them cleaned.