Where to Check Your Furnace When It Is Not Working Properly

Where to Check Your Furnace When It Is Not Working Properly

December 7, 2022


Vibrations are generally not good with anything mechanical unit, especially if we're talking about excessive shaking accompanied by loud noises. This definitely applies to your air conditioning system. If this is what's happening with your AC, the first thing you need to do is shut it off. As for why your A/C unit may be shaking in the first place, we'll go over some possibilities below.

Where to Check Your Furnace When It Is Not Working Properly

What Should I Check When My Furnace is Not Working? (Master Mechanical)

When it comes to the wintertime chill, a home furnace is one of the best ways to beat it. While you may do your best to perform regular maintenance on your furnace, it can break down from time to time. Knowing the most common causes and how to fix them can help you get your furnace back up and running quickly.

Air Filter

If your furnace is on and it feels like little air is coming out of your ducting, it's time to check your air filter. When an air filter reaches the end of its lifespan, it will become clogged and full of debris. When this happens, it will heavily restrict the airflow through the filter and into your ducting. Simply replacing the dirty filter with a new one can easily solve this problem.

Dirty Ignition Sensor

If you hear your furnace start up but don't see it light, it could be a dirty flame sensor. It's best to open the access panel and watch your system run. Make sure you depress the door switch, as leaving it open will prevent your system from running. Once you hear your furnace click on, you should see your ignitor glow bright red.

If it doesn't ignite the gas, then it's likely that your ignition sensor is the problem. Turn off the gas and your HVAC system. Next, you'll want to locate the flame sensor and clean it with an emery pad. Reinstall it and see if that fixes your issue. If it doesn't, you'll likely want to call an HVAC professional to replace your faulty ignition sensor.

Check Your Thermostat Settings

Your thermostat is the brains behind your entire heating system. You should check over your settings to ensure that they're correct. If this is the first time you'll be running heat after using air conditioning all summer, you may have forgotten to switch from cool to heat mode. Ensure your temperature is at least a few degrees above the ambient room temperature.

Check for a Tripped Breaker

If you have constant power surges in your area, your furnace may have simply tripped its breaker. Head to your panel box and locate the breaker for your furnace. If it's tripped, switch it to the off position and back to the on position. This should solve the issue, and your furnace should start immediately.

Check Your Fuel Source

Another common reason your furnace may not run is that it doesn't have an adequate fuel supply. Check your fuel storage tank to ensure you don't run out of fuel. If you have natural gas, check to ensure your gas supply line is on at the meter.

Call Us Today

If you're having an issue with your furnace, it's time to contact us at Master Mechanical. Let our experienced HVAC professionals assist you in getting your furnace back up and running as quickly as possible.


See all articles

Proof We’re the Best HVAC Company Straight From Our Customers

  • Didn’t Push a Furnace Replacement
    Taylor D.
    Tom, the owner was awesome. He came out immediately when our furnace went out and completed a challenging fix. When I asked if I should replace the furnace he said no. Honest and did outstanding work. Furnace is quieter and seems to be running better than when we moved in!
  • Highly Recommended for AC Replacement
    Jeremiah D.
    Tom came over and thoroughly discussed my options. We discussed at length the pros and cons of the most expensive and least expensive options, and came up with a fair price for the products I chose. The crew showed up on time and finished the same day, and was easy to deal with. The new furnace heats my house so much better than the old one. I would definitely use Master Mechanical again. And I have. I’ve now replaced multiple furnaces and AC units using Tom and his crew at Master Mechanical, and would use them again.
  • Quick AC Fix During a Power Surge
    Jim P.
    Master Mechanical responded quickly when our AC failed following a power surge. They quickly diagnosed the problem, and responded patiently to my uninformed consumer questions. Once the team arrived to complete the repair work, they were professional and again, knowledgeable. Prices were fair, and they followed up with me after work was completed. Overall a great company!
  • Last Minute AC Repair
    Rupal P.
    Master Mechanical is an amazing company! I called last minute (per my friend's recommendation) since my ac broke yesterday. Victor was friendly, fast and explained everything and he ended up fixing my issue---thank you! Highly recommend Services A/C system repair.
  • Two Great HVAC Experiences
    Bill L.
    Did an excellent job on two repairs. The first was an emergency call for a furnace repair when it was 4 degrees F outside. They showed up on time, diagnosed the problem, went for parts, repaired the furnace all in about an hours time. The second repair was for the whole house humidifier attached to the furnace. It was a minor issue and corrected in less than 40 minutes. Everything is working great. My experience with their work is excellent.