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Furnace Troubleshooting

Furnaces, like all things in life, can have problems. When you notice that your furnace is acting up, you can try a few things before you call a service technician out to your home. Here are a few things that you can try before spending money on a service call.

1.     Check the Filter

One of the most common issues with poor air flow or inadequate heating is a dirty, clogged air filter. In severe cases, a dirty filter can even prevent your furnace from kicking on, which could be a good thing, because a dirty furnace is a fire hazard. To check your filter, you need to:

  1. Turn off both the furnace and thermostat.
  2. Remove the filter and hold it up to the light. If light doesn’t pass through the filter easily, you should clean or replace it.
  3. Install the new filter using the arrows on the filter to make sure that the filter is properly installed.
  4. Secure the access panel and restart your furnace and thermostat.

Prevent a dirty air filter by checking it every month. Keep back-up filters on-hand in case your filter ever needs replaced.

2.     Check the Thermostat

If you have a clean, properly installed air filter and your furnace still won’t turn on, check the thermostat. The first thing you should look at is whether the thermostat is set to heat. If it is, but you aren’t feeling warm air in your home, set the thermostat to five degrees warmer and see if the furnace kicks on.

You should also make sure that the batteries don’t need to be replaced. Dead batteries will prevent the thermostat from sending information to your furnace, which can lead to your home feeling very cold in the wintertime.

Electromechanical thermostats can become dirty, which can cause them to stop working properly. Dust the thermostat by opening it and using a soft paintbrush to brush off all of the built-up dust and dirt.

Finally, make sure that your thermostat isn’t located someplace that could cause false readings. If there are lamps, space heaters, windows, ovens, or other heat sources near the thermostat, it could be sensing that your whole home is as warm, and your thermostat won’t kick on.

3.     Check the Furnace Switch

In some cases, the problem may not be the furnace at all. You could be having problems with power getting to the furnace or thermostat. To check the power to your furnace, follow these steps:

  1. Check the furnace switch near the furnace. It may have gotten switched off accidentally. If you flip it back on and it still doesn’t work, you need to check the electrical panel.
  2. To check the electrical panel, you need to turn the power off at the breaker or fuse box.
  3. At the breaker, make sure that the switch for the furnace is flipped to the ON position.
  4. If the breaker is set to ON already, reset it by flipping it all the way off and then back on again.
  5. If you need to restore power to your fuse box, you should look for a melted or discolored fuse. If you find a damaged fuse, contact a professional to fix the problem.
  6. Turn the furnace switch back on. If the power doesn’t turn back or the breaker continues to trip, you will need to contact a professional.

4.     Check the Furnace Flame

The furnace flame should glow a blue color. While there may be a yellowish tip to the flame, the majority of the flame should be blue, as this signals that fuel is being burned safely and efficiently.

If the flame in your furnace is any other color, including red, yellow, purple, or green, you need to call out an HVAC professional right away. This problem should never be fixed by anyone other than a professional.

5.     Check the Vents

Another main cause for uneven heating in a home is closed or blocked vents. Inadequate airflow can cause rooms in your home to feel much colder than they should be. Find the vents in your home, make sure they are open, and check that there is nothing covering the vents, such as a rug or piece of furniture.

While you may not realize it, blocked vents can also lead to duct leaks, as the air pressure in the ducts becomes too much for your ducts to handle. You may also need HVAC repairs more frequently if you have closed or blocked vents in your home.

If you ever feel uncomfortable performing any type of troubleshooting on your furnace, it is best to contact an HVAC professional. In the Kansas City Metro Area, Cates Heating and Cooling is here to check out your HVAC system to ensure that your furnace is running properly and as efficiently as possible. Even better, sign up for an annual furnace maintenance check to have a professional check over your heating system each year before the cold weather hits. These maintenance checks can prevent potential problems with your furnace system throughout the winter months.

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