What Are The 10 Most Common Furnace Problems

  1. Thermostat Isn’t Working. …
  2. Dirty & Clogged Filters. …
  3. Flickering, Weak or Oddly Colored Pilot Light. …
  4. Cracked Heat Exchanger. …
  5. Malfunctioning or Frayed Blower Belt. …
  6. Frequent & Over-Cycling. …
  7. Limit Switch Malfunction. …
  8. Furnace Isn’t Blowing Air.

What would cause a gas furnace not to kick on?

If your furnace is not turning on you should first check if the filter is clean. Dirty filters cause insufficient airflow and can prevent the furnace from starting. Other reasons it won’t start can stem from improper thermostat settings, forgetting to turn on the gas line, or faulty pilot light.

How do you reset a gas furnace?





Follow these simple steps:

  1. First, turn off the power supply to the furnace by turning off the breaker in the circuit box.
  2. Locate the reset button on the furnace and press it to reset the furnace. …
  3. If the button is popped up, press it down.
  4. Return the cover to the blower compartment and turn the power on.


What to check when furnace is not working?

Furnace Not Working? The 5 Most Common Causes [2019]

  • Step #1: Check your Air Filter.
  • Step #2: Check Your Pilot Light.
  • Step #3: Check Your Thermostat.
  • Step #4: Check The Power.
  • Step #5: Check Your Gas Supply.


Where is the reset button on a furnace?





Locate the reset button on the furnace and press it to reset the furnace. It is usually located inside the blower compartment on the side of the blower motor. Be cautious as the housing may be hot. If the button is popped up, press it down.

Why is my furnace not responding to thermostat?

When a furnace is not responding to a thermostat, there is either a problem with the heating unit or the actual thermostat. Lack of power to the thermostat, wrong settings, and outdated software might be to blame, as well as faulty wiring, a tripped breaker, and a dirty furnace filter.

How many times can I hit the reset button on my furnace?

Don’t hit “reset” more than twice. The process pumps oil into the burner chamber, where it can accumulate if you have no ignition. Then when the furnace finally does start, it can do so explosively. So if the button won’t reset, or quickly pops up again, it’s time to call a professional repair service.

Why is my furnace blowing cold air when the heat is on?

If your furnace is blowing cold air in your home, this is a sign of an issue with the flame detector, gas supply, air filter, pilot light, or condensate lines. Many of these issues are able to be easily solved on your own by sanitizing or replacing components in the gas furnace.

Why is my furnace running but not blowing hot air?



The Furnace Is Blowing Cold Air



First, check to make sure the thermostat is set correctly. You will want to make sure that the fan control is set to auto, and not ‘on’. If the thermostat appears set correctly, turn off your heater at the thermostat and check the filter. If the filter is dirty, replace it.

Why is my furnace running but no heat?

Dirty filters are the most common cause of furnace problems. Dust and dirt restrict airflow—and if the filter gets too clogged, the heat exchanger will overheat and shut off too quickly, and your house won’t warm up. If the blower is running but no heat is coming out, replace the filter.

Why is cold air coming out of my vents when the heat is on in my car?

Low Coolant Level



The coolant (usually a mixture of water and antifreeze) in your engine doesn’t just work to keep the engine from overheating: It’s also the source of heat supporting the heating system. If there isn’t enough coolant in your system, the heater core will blow cold air into your car.

How do I know if my heater core is clogged?



This could be due to a clogged or failed heater core, which is responsible for dispensing warm air into the cabin via the blower motor.



Key signs to look out for:

  1. Weak or no airflow.
  2. Cold air (not warm) coming through the vents when the heater is on.
  3. Coolant leakage visible inside the cabin or a damp smell.


How do I unclog my heater core?

Quote from the video:
Quote from Youtube video: I'm going to show you how you can take off the hoses that go to the heater core attach this to the water hose blast it out and within a few seconds your heater core will be unclogged.

Why does my heater get hot then cold?

This problem could be either an engine thermostat that is not keeping the engine at a constant running temperature (temp gauge steady in the center), or the heater control valve or controls are malfunctioning not allowing engine coolant into the heater core (passenger compartment).

Why does my heat not work sometimes?



Dirty and clogged filters are one of the primary causes of furnace problems and can cause high operating costs. The heat exchanger can overheat and shut off quickly when filters are clogged with dust and dirt. This also causes soot buildup on the heat exchanger, which makes your furnace run less efficiently.

How much is a new furnace?

A new furnace costs $1,500 to $6,500, depending on the model you choose. The average cost of installing a mid-efficiency furnace is $1,500 to $2,500. Mid-efficiency furnaces have an annual fuel utilization efficiency (AFUE) rating of 80% to 89%.