How To Check A Broken Furnace

Now that the cooler weather is here, it’s time to start thinking about heating your home. Next in my HOW series are some quick tips for how you can check for a broken furnace or heating unit. If you do not feel comfortable following these steps, simply call a licensed and professional heating contractor to perform a System Inspection for you. 
First, turn on your furnace to check that it’s operable if you haven’t operated the heat so far this season. To do so, switch your thermostat to heat mode and increase the temperature. If there is no hot air, try turning up the thermostat to a higher temperature. There will probably be a short delay, typically less than a minute, before the blower comes on and starts moving warm air. You should feel the air from the vents warming quickly. If you hear no air moving after a couple minutes or feel no difference in temperature, switch the thermostat to the off position. 
Check for dust or dirt in or around the thermostat by lifting the thermostat cover. Dirt can impact the thermostat’s calibration. Be careful not to jar the thermostat’s components, this can cause the thermostat to malfunction. It’s also important for some older thermostats to be level on the wall, so check that the thermostat is perfectly level. If there is excess dirt or corrosion, replace the thermostat or seek a professional to replace it for you. If the thermostat is operating properly and appears clean and level, it may not be the culprit. 
Go to the fuse box and check the fuse or circuit breaker for the furnace. Even if your furnace is already operating properly, it’s a good idea to check your home’s circuit breakers regularly. If the circuit breaker for the furnace is tripped to the off position (or half-way), switch it fully to the off position, then firmly return it to the on position. If it trips back to the off position again immediately or in a short period of time, there could be a problem requiring professional repair service. Do not attempt to adjust the electrical service box yourself. 
If the furnace circuit breaker was not tripped or you resolved the situation, try turning on the thermostat again and see if there is hot air. If there is still no warm air or the system remains inoperable, examine the outside of the furnace itself for any obvious problems, like a buildup of dirt and dust, burn marks, unusual noises or any other indications of a potential problem. If your furnace is a newer high efficiency model, it may be vented out to one of the side walls of your home. Check the vent pipes to be sure they are unobstructed and there is nothing blocking the opening. While there, check your furnace filter and replace or clean it . Air filters should be checked at least every three months. 
Finally, if they can be accessed, examine the duct work for any signs of cracking or unsealed joints. If you notice any of these issues it’s probably due to a lack of professional maintenance. A Precision Tune-up will include a heating system cleaning and visual inspection of the heating system and provide solutions to any furnace repair problems. 
If any furnace or heating problems still exist or remain unresolved, call an experienced ACE-certified heating contractor to rectify the situation with necessary repairs and Precision Tune-up

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