Furnace Troubleshooting

Furnace RepairFurnaces, 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.

Schedule a service or maintenance check with Cates Heating and Cooling today at 913-888-4470. Our team can make sure that your family stays warm all winter long.

Furnace Repair Costs

When it comes time to make necessary repairs on your furnace, you want the best deal with outstanding service. Cates Heating and Cooling provides the service you are looking for, and we are transparent with our furnace repair costs. We want you to get the best deal on your HVAC repairs. Here are a few of the most common furnace repairs that we see, what it costs to fix the problem, and why.

Flame Sensor Cleaning

Furnace RepairAt Cates Heating and Cooling, the most common furnace problem we see is actually a maintenance problem. In gas furnaces, the flame sensor is an important piece of safety equipment. The flame sensor produces a current of electricity that is measured in microamps. Throughout the ignition sequence, gas is either ignited by a spark or hot surface igniter. At this point, the flame sensor produces the electricity that the control board needs to read. If the amps aren’t reading at the right level, the furnace cuts off the gas to avoid an explosion.

The flame sensor gets dirty over time due to oxidation or carbon buildup. This interferes with the sensor’s ability to function properly, and in turn, the system will shut down. Cleaning this sensor is very important, and one of our expert technicians can clean your flame sensor in just a few minutes. Generally, the cost for cleaning the flame sensor is just the service call fee, so at Cates Heating and Cooling, you are looking to pay $98. For most customers, it is easier to get started on a service plan where a Cates technician will come out to inspect and perform maintenance on your furnace annually.

Air Filter Cleaning

If your furnace shuts off for seemingly no reason, your air filter could be the culprit. Unfortunately, it is very easy to forget to replace your dirty air filter frequently. When air filters get dirty, there isn’t enough air getting through the filter, and the furnace will overheat. Since there are safety measures in place, when the furnace overheats, the unit will shut off. Many people don’t realize that their air filter is the problem and will call out a service technician.

Fortunately, replacing an air filter is relatively cheap. An air filter may be just a few dollars if you want a cheap one that you can replace monthly. There are more expensive options, however. When a Cates technician comes to your home and determines that the air filter is the problem, you will only be charged the $98 service fee unless you want to purchase an air filter from us at that time.

Air filters can cause a myriad of problems for furnaces, so before you call a technician out to your home, you should make sure that your air filter isn’t clogged. You can also use a calendar to remind yourself to replace your air filter once a month.

Pressure Switch

Furnace ReplacementThe pressure switch is a safety mechanism that ensures that all the exhaust gasses from your furnace aren’t pulled back into the furnace—a process called backdrafting. The pressure switch also protects your home from gas leaks, and it shuts down the furnace in the event of a mechanical failure. Without the pressure switch, your home could be at risk for carbon monoxide problems.

A pressure switch with labor generally costs between $50 and $150. Price will generally depend on the type of pressure switch you need.

Blower Motors

Blower motors turn the fan in your furnace to circulate the air out of the furnace and throughout your home. Eventually, your blower motor will go bad. These pieces of equipment push gas out of your home to prevent any problems with carbon monoxide in your home. If the blower motor in your furnace goes out, the furnace will not run.

The price of a new blower motor will depend on its style, age, and efficiency, but they generally cost between $350 and $900.


There are a few different kinds of igniters available, but the hot surface igniter is a silicon carbon element that heats up when voltage is applied to it. When you turn your furnace on, the furnace circuit board sends electricity to the igniter. Then, the main valve opens, and gas strikes the hot surface igniter element and ignites. Hot surface igniters light the gas to allow the furnace to heat your home. Eventually, igniters will need to be replaced.

These little pieces of equipment may seem expensive to some, but they last anywhere from five to 12 years depending on how well they are kept. Typically, with installation, hot surface igniters cost between $80 and $350.

If your furnace is experiencing any problems, contact us today at 913-888-4470.