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How To Troubleshoot Your Home Furnace

troubleshoot your home furnace

If your furnace is not heating or not turning on at all read below to learn more about how to troubleshoot your home furnace. These common scenarios can help you determine if it is a problem you can fix yourself or if you need to call a professional. Since heating your home on a cold winter day is essential for a comfortable home, it is important to identify and promptly fix any furnace issues. By promptly addressing the issues at hand you can help ensure a minor problem, does not turn into a major costly repair. Most importantly keep in mind, that in order for your furnace to keep up with winter demand, it is important not to neglect necessary regular maintenance.

Check Your Thermostat

A faulty thermostat will not cause your furnace to fail, but it can prevent a furnace from operating properly. If you are experiencing any issues with your thermostat, the easiest and fastest step you can do is to check your thermostat first. First double check that the thermostat is set to heat and the temperature is set at your desired level above the current room temperature. If it is not, turn the temperature up by at least three degrees above the current room temperature and see if it makes a difference. Be sure to also check the batteries if you have a battery powered thermostat. Change the batteries if they are dead, so thermostat can properly communicate with your furnace. If after setting a higher temperature and checking batteries your heat is still not working, check if the thermostat is configured properly. The thermostat must be properly set to work with your HVAC system or it will not work. In order to do this you can consult your user manual to ensure the settings are set to match your HVAC system.

Check Power to Furnace

In order for the furnace to operate at all the system must have power. First check the switch near the furnace and ensure it is in the ON position. Verify that it is in correct position by inspecting the switch itself before making any conclusions. If the switch is on and furnace is not turning on, check the main circuit breaker panel. Ensure all breakers are in the on position. Look for the switch marked furnace and flip it to on. If they are not marked look for the switch in the opposite way and flip it back to on position.

Check Gas Source Is On

Check to see if the gas valve was somehow turned off accidentally. If you suspect a gas leak call gas company immediately as it could be dangerous. If you check near the furnace there should be a valve on the gas line with the lever in line with pipe or gas flex pipe leading to the furnace. However, if the lever is perpendicular to the line, the gas is turned off. Don’t just turn it back on, consult with your gas company or professional as to why it was off. Furthermore, furnaces fueled by natural gas can be impacted by issues with the natural gas line. Keep in mind that gas is toxic, so any issues with gas supply line must be addressed by a professional.  

Check Pilot Light Is Staying On

If your furnace has a pilot light or electrical ignition system it could have a malfunction that is affecting proper operation of your system. A failing pilot light will not ignite the burners and the furnace will not produce heat. A pilot light that will not stay on may be due to a faulty thermocouple. In some cases the thermocouple may need to be adjusted or replaced. Contact a professional who can determine what is necessary to get your furnace up and running. Ideally your pilot light should be checked at least once a year during routine maintenance.

Check Burner

If the burner is not staying on it could be due to a dirty flame sensor. The flame sensor detects whether or not there is a flame in the combustion chamber. If the flame sensor is dirty it causes the burner to be unable to detect a flame. Another reason for the burner not to stay on may be due to a tripping pressure switch. A pressure switch is a safety component in newer systems. The pressure switch will shut your unit down if it detects the venting in your system is not working properly. Improper venting can be a result of clogged air filters or blocked registers. Contact a professional who can determine why it is not staying on.

Check Filter

The system must have proper airflow in order to operate properly and efficiently. If your furnace is not getting adequate airflow it will not work properly. Inadequate airflow can be caused by covered returns, closed registers or dirty filters. A dirty air filter not only affects the air quality of your home but can shut your furnace off to avoid overheating. The air filter is in place to prevent dust, debris, or other airborne contaminants from circulating in your home, but also to keep your furnace operating efficiently. It is important to check your filter and replace it at least once every three months to allow for proper airflow.

Issues with Blower Motor

The furnace blower motor works with other components in your system to circulate the warm air throughout your home. If there is an issue with the blower motor any of the other components such as fan motors, belts or bearings may be at fault. During routine maintenance your blower motor should be inspected. If your furnace is on and working properly but air is not circulating throughout your home it may signal an issue with the furnace blower motor. Calla professional to further diagnose and repair this issue.

Furnace Maintenance

In order to lower the chances of you having to troubleshoot your furnace, the number one easy step you can take to prevent furnace issues is to schedule regular furnace maintenance. Routine maintenance completed by a professional can identity any issues that may lead to major costly repairs. During regular maintenance a professional will inspect furnace components for signs of damage and make sure furnace is operating properly. In the long run, regularly scheduled maintenance can save you on future costly repairs and unexpected failure in the middle of winter. Regular maintenance also leads to lower energy bills and may even extend the life of your HVAC system.

When To Contact A Professional

Whenever you’re uncomfortable or are stuck during an uncomfortable stage call a professional. Remember to always take extra precautions to prevent injury. Some repairs will require a professional due to severe issue or to replace a part. If you troubleshoot your furnace and your furnace will not turn on call a professional. It is especially important when the system is short cycling, gas line issues, faulty pilot lights or strange noises are coming from your system or if you need to replace any gas furnace components. If you believe your furnace was installed improperly call a professional it may lead to a gas or carbon monoxide leak as well. Professional, experienced technicians can troubleshoot these furnace problems and get your home warm again.

If you need a professional diagnosis or notice something does not seem quite right with your furnace, give LA Construction Heating and Air a call at 818-341-3406 or contact us online. The most important step you can take is to schedule regular maintenance for your HVAC system and don't neglect your gas furnace. Regular maintenance can reduce the amount of repairs that may be needed in the future. Keep in mind that during a scheduled maintenance appointment, our professionals will check key, safety components and clean your system. In between maintenance appointments, change your air filter regularly and address any issues promptly. Give us a call today, we’re here to help. To learn more about services our company offers, please visit our homepage.

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As Benjamin Franklin said, an ounce of prevention is worth a pound of cure. Same idea applies to your central heater and air conditioner maintenance.Think of it as an oil change for your auto, which improves your car's engine performance, maximizes your gas millage and minimized down time by avoiding unnecessary repairs.

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