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Schaal Plumbing, Heating and Cooling Blog

Reasons a Furnace May Blow Cool Air

furnace-wiringWith the most extreme of winter weather (hopefully) behind us for the year, it is safe to say that everyone is ready for things to start warming up once again. Just because you are ready doesn’t mean that ol’ mother nature is quite there yet, unfortunately. We’ve got some chilly weather coming our way still, and chances are that you are going to be running your furnace for a while longer yet, even if it’s more sporadic than it has been.

That is precisely why, even this late into the heating season, it is vital to keep your home heating system in the best working condition possible. This means more than just having your furnace tuned up annually and changing filters as needed. It also means taking prompt action when problems of any kind with your furnace surface. And even the best furnaces with the best of care will eventually require professional furnace repair in Urbandale, IA.

You’ve Only Got the Fan On

Let’s start out with something of a best-case scenario. You may simply have the furnace set wrong. No, we don’t mean the temperature. Remember, a lower temperature setting doesn’t really mean that the air is any cooler when heated by the furnace, but that the furnace shuts off when ambient room temperatures hit a lower level. What we’re actually talking about is the heat vs. fan-only setting.

If you’ve only got the fan engaged, then your HVAC system is only circulating air throughout the house. The furnace is not actively heating the air. If your home has really cooled down significantly, then it is going to feel as though your furnace is blowing cooled air as a result. Simply changing the setting at the thermostat will get your comfort back on track.

You’ve Got a Very Dirty Filter

We’ve talked about how important it is to keep fresh filters in your furnace many times before, and we’ll continue to do so. Why? Because it’s that important! Dirty filters can cause short cycling, increased energy costs, and other issues—including the one we’re focusing on today.

If your filter is too dirty, then your furnace can overheat. That can lead to short cycling, certainly, but it can also lead to an interruption in the actual heating of air while the fan continues to run. When the thermocouple senses that internal temperatures are too high, the fuel delivery and combustion will be cut off. You may feel cool air coming from your furnace as temperatures drop if it doesn’t cycle down completely.

You’ve Got Leaky Ducts

You’ll need them professionally repaired in this case. If you notice that just one area of the home seems to have cool air coming from the vents, then leaky ducts servicing that area are a very likely issue. The ducts can leak heat into unconditioned spaces that don’t really need it, and then you’ll wind up with cooler air entering the spaces where you want the heat!

These are just a few examples of why your furnace may blow cool air. Any other number of situations could also result in the problem and may require professional furnace repairs.

Contact Schaal Plumbing, Heating and Cooling for dependable furnace services.

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