Common Furnace Problems

If you live in Colorado, your home’s furnace is an essential appliance for much of the year. If you’ve ever had to live with no heat in a Colorado winter for any length of time you know just how crucial that thing is, so it’s important to keep it in good shape and keep an eye out for potential issues. Here are some of the most common furnace problems that you may experience (but hopefully not.)

A Cracked Heat Exchanger

A gas furnace has a heat exchanger, which is a thin metal piece between the blower and the combustion chamber. As the chamber heats the exchanger, heat transfers to the air being blown across the surface. This hot air is pushed on through ducts and sent out your supply vents to heat your home. The heat exchanger must have an air-tight seal in order to keep the flue gasses out of your home, as the gasses from the combustion process can be bad for your health. This includes carbon monoxide, which can be deadly.

Because this process makes the heat exchanger expand and contract, which causes metal fatigue, these parts usually don’t last beyond 20 years. They can also get clogged. Symptoms of a faulty heat exchanger include cold air, a bad smell like formaldehyde, high carbon monoxide levels, a pilot light that flickers and/or isn’t blue, discolored metal or soot buildup on your furnace, or excess condensation. Unfortunately, it takes special equipment to professionally diagnose a broken heat exchanger, and the repair can be costly

Thermostat Issues

The best furnace in the world won’t do much good without a good working thermostat. If you’re having furnace issues, check the thermostat settings first. Make sure it’s set to a reasonable temperature. Setting it too high will overwork the furnace and the blower. Same goes for the fan setting. Make sure it’s set to Auto instead of On. Having it always on will strain your system and waste energy. Some thermostats use batteries that have to be changed out every two to three years, so keep that in mind if your thermostat is glitchy or unresponsive.

Clogged or Dirty Filters

If your HVAC filter is clogged up with dirt, dust, hair and other debris, your heater will have a really hard time heating your house. This can also cause problems with the air quality in your house. Every two to three months, check your air filter. Hold it up to the light. If it lets no light through, it definitely needs replacing. If it’s a permanent filter, rinse it with a hose or faucet and let it dry completely before putting it back in. Make sure your heating system is turned off while you’re checking and servicing your air filter, or else your HVAC system will be blowing unfiltered air into your home.

Slipped or Frayed Blower Belt

If your heating system is making a high-pitched squealing sound, the problem is probably a slipped or frayed blower belt. This belt connects to a motor and turns the fan which blows hot air into your home. As with the belts in your car, these parts don’t last forever. A malfunctioning fan will make your whole system less efficient.

Worn Out Ball Bearings

Ball bearings allow your fan to turn smoothly. If you have a grinding noise when the fan is working, the problem may be worn-out ball bearings. This requires a professional diagnosis and replacement. New ball bearings will improve your fan’s efficiency.

Rattling or Pinging Noises

If you hear rattling noises when your heater is on, there are a few possible causes. There may be a loose bolt somewhere or loose paneling. A popping or pinging noise is usually related to ducts, which expand and contract depending on whether you’re using heat or AC. This is very normal to hear when it’s your first time of the season using heat or AC. But if you hear it often it could mean the ductwork is damaged. Call a professional over to have a look.

Furnace Isn’t Blowing Air

If there’s no air at all coming from your supply vents when you’re trying to run the heat, it’s probably an issue with the blower. Go down and see if the fan is turning. If a red light is on, your blower needs professional maintenance. Another possibility is that your fan is clogged with debris. Make sure the HVAC system is turned off before any attempt to clear debris.

Blowing Cold Air

If your heating system is blowing cold air into your house, there are a number of possible causes. This will seem like a no-brainer, but first check the thermostat to see if someone switched the system to Cool instead of Heat. Check the temperature setting. If the thermostat looks fine, the pilot light may have gone out, or there may be a problem with your natural gas supply or heat exchanger. If you have an electric furnace, there may be an issue with the coils that heat the air that is sent into your home.

The Blower Is Always On

If your blower is running all the time, check to make sure the thermostat is set to Auto instead of On. If it is, there may be a problem with your limit switch, which turns your blower on and off. Unfortunately, this problem requires professional attention and can mean a costly repair or replacement.

If you need repair or professional maintenance for your home furnace or HVAC system, call the Allen team. Allen Service has been servicing Fort Collins, CO homes for over five decades. Owners and brothers, Mike and Jeff Allen are the third generation of the Allen family to run the business. They carry out the tradition of delivering excellent customer service and high-quality parts for all plumbing, heating, and air conditioning projects to your home. When you work with Allen Service, you are working with the best!