Aug 15, 2024

Home Maintenance

Furnace Acting Up? Common Furnace Problems & Solutions

Fix your fickle furnace.

As the temperature drops and the chill of winter sets in, your home's furnace becomes one of the most important appliances. It keeps your home warm and cozy, but what happens when it starts acting up?

Today we're exploring some common furnace problems and how you can solve them. Make sure your home stays warm all winter long with this guide easy DIY furnace fixes.

Common furnace issues (and how to fix them)

1. Furnace won't turn on

Problem: You set the thermostat to a warm temperature, but the furnace just won't start.

Solution:

  • Check the thermostat: Make sure your thermostat is set to "heat" and the temperature is set higher than the current room temperature. Also, check if the batteries need replacing.
  • Power supply: Ensure that the furnace's power switch is turned on. If it’s a gas furnace, make sure the gas valve is open.
  • Circuit breaker: Sometimes, the circuit breaker might trip. Locate your breaker box and see if any switches are in the "off" position. If so, flip them back to "on."

2. Inadequate heat

Problem: The furnace is on, but your house still feels cold.

Solution:

  • Filter: A dirty filter can block airflow and reduce the furnace's efficiency. Check the filter and replace it if it's dirty. It's a good idea to replace the filter every 1-3 months during the heating season.
  • Thermostat settings: Double-check your thermostat settings. Make sure it's set to the right mode and temperature.
  • Air vents: Make sure all air vents are open and not blocked by furniture or curtains. This allows proper airflow throughout your home.

3. Frequent cycling

Problem: The furnace turns on and off frequently.

Solution:

  • Filter: Again, a dirty filter can cause many issues. Check and replace the filter if necessary.
  • Thermostat location: If the thermostat is located near a heat source (like a sunny window or a heat-emitting appliance), it might get false readings. Move the thermostat if possible.
  • Blower motor: The blower motor might be overheating and shutting down. If you suspect this, it might be best to call a professional.

4. Strange noises

Problem: Your furnace makes banging, squealing, or rattling noises.

Solution:

  • Banging: This could be due to expanding and contracting ducts or a dirty burner. Check the ducts and clean the burner.
  • Squealing: This usually means a slipping or worn-out blower belt. You might need to replace the belt or adjust its tension.
  • Rattling: Loose panels or screws can cause rattling noises. Tighten any loose screws or panels you find.

5. Blower running continuously

Problem: The blower runs all the time, even when the furnace isn't heating.

Solution:

  • Fan Setting: Check the thermostat to see if the fan is set to "on." If it is, switch it to "auto" so the fan only runs when the furnace is heating.
  • Limit Switch: The limit switch could be faulty. This switch tells the blower to turn off when the air reaches a certain temperature. If it's not working, you may need a professional to replace it.

6. Pilot light problems

Problem: The pilot light won't stay lit.

Solution:

  • Draft: Check for any drafts around the furnace that might be blowing out the pilot light. Seal any drafts you find.
  • Thermocouple: The thermocouple might be faulty. This is a safety device that shuts off the gas if the pilot light goes out. If it's not working, you'll need to replace it.
  • Pilot Orifice: The orifice might be clogged. Clean it carefully to ensure the pilot light can stay lit.

7. Furnace smells funny

Problem: The furnace emits strange odours.

Solution:

  • Dusty smell: A burning dust smell is common when you first turn on the furnace for the season. If the smell persists, clean or replace the filter.
  • Musty smell: This could indicate mold in the ducts or the furnace itself. Clean the ducts and the furnace to get rid of the mold.
  • Gas smell: If you smell gas, this could be serious. Turn off the furnace, evacuate your home, and call your gas company or a professional immediately.

8. Furnace leaks water

Problem: You notice water pooling around the furnace.

Solution:

  • Condensate line: High-efficiency furnaces produce condensation. Check if the condensate line is clogged or leaking and clean it out.
  • Humidifier leak: If your furnace has a built-in humidifier, check for leaks. Repair or replace any faulty parts.
  • Flue pipe: If the flue pipe is blocked or improperly installed, it can cause condensation. Ensure the flue pipe is clear and properly installed.

9. Furnace turns off too soon

Problem: The furnace shuts off before reaching the desired temperature.

Solution:

  • Thermostat Placement: Again, check the placement of the thermostat. If it's too close to a heat source, it might think the house is warmer than it actually is.
  • Short Cycling: This can be caused by an oversized furnace. If the furnace is too powerful for your home, it heats up too quickly and shuts off. You may need to consult a professional to address this issue.

10. No air coming out

Problem: The furnace is running, but no air is coming out of the vents.

Solution:

  • Blower Fan: The blower fan might not be working. Check if it's running. If not, you might need to replace it.
  • Blocked Ducts: Make sure the ducts are not blocked. Inspect them for any obstructions and remove them.
  • Filter: Yet again, a dirty filter can cause many problems. Replace the filter if it's dirty.

Troubleshooting your furnace problems

A homeowner tinkers with his furnace

Keeping your furnace in good working order ensures a warm, comfortable home during the cold winter months. Regular maintenance, like changing filters and checking thermostat settings, can go a long way in preventing many common furnace problems.

While many furnace problems can be fixed with a bit of troubleshooting and basic maintenance, some issues require professional help. If you're ever unsure or uncomfortable with performing any repairs, call Rümi's certified HVAC technicians. We have the know-how to fix furnace issues efficiently and keep your system running through Alberta's harsh winters.

Remember, a well-maintained furnace is a happy furnace, and a happy furnace means a warm and cozy home for you and your family. Stay warm this winter!