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Serving The Fresno & Madera Area

70th Anniversary of Purl's Sheet Metal & Air Conditioning

Serving The Fresno & Madera Area


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Off to a Slow Start … Is Your Furnace Not Giving You Enough Heat?


As we move into the colder months of the year, your furnace will begin running more often. You’ve probably already had it on a few times—and we hope you’ve called us to arrange for heating system maintenance. (If not, now is a great time to have it done!)

You may notice as the winter starts that your furnace isn’t living up to expectations. There are cold spots in rooms, the general household temperature feels lower, and you have to fiddle around with the thermostat to get enough heat. These are all warning signs you may need furnace repair in Fresno, CA, and we don’t recommend you wait long to call us to schedule them. What might seem like a small trouble can balloon into a larger one, and you also want to avoid any potential safety hazards.

Below we’ll look at why your furnace may be off to a slow heating start.

You forgot to change the air filter

We’ll get this one out of the way first, because it’s a common problem and one you can correct quickly on your own. A furnace needs a clean filter to start out the season. If you still have the same filter in the HVAC system from the summer, it definitely needs to be exchanged for a clean one. A clogged filter restricts a furnace’s ability to heat up enough air for comfort.

Remember to schedule maintenance

If you have your furnace running before you’ve scheduled professional maintenance for it, we’re not surprised it isn’t performing well. A furnace that’s dirty and worn down from a previous year of work will struggle at its job. Have a maintenance appointment arranged with us ASAP.

The thermostat is miscalibrated

You may not have a problem in the furnace components themselves, but with the thermostat for the house. Thermostats can become miscalibrated, causing them to pick up incorrect temperatures. If your thermostat registers the house is warmer than it is, it will shut down the furnace too early. You can have our technicians recalibrate the thermostat to fix this.

Problems with gas supply

It’s possible the furnace can’t heat up the air moving through it because of problems with the gas supply to the burners. The burners may not be fully igniting, or they are shutting off early. There might be blockage in the gas line. Please don’t attempt to do any detective work on your furnace’s burners or gas lines—this can be hazardous, so leave the work to our professionals.

The furnace is too old

Your furnace may simply have reached the point where age has worn it past effective operation. Although a targeted repair might get it back working at the level you want, such repairs are often too expensive to be worth it and will only temporarily hold the furnace together. We recommend replacing any gas furnace that’s more than 15 years old.  

Call Purl’s Sheet Metal & Air Conditioning if you need help with an underperforming furnace. Uncompromised Quality & Customer Service Since 1954.

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