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Your Indianapolis Licensed HVAC Contractor


Your Indianapolis Licensed HVAC Contractor


Vital Heating & Air Blog

Why Won’t My Furnace Heat the Whole House?


When you had a central furnace installed in your home, it was for the whole home—at least all the living spaces. (You probably don’t heat the garage or the attic.) You expect the furnace to spread heat through the ductwork to reach all the vents and provide an even distribution of comfort.

So if you turn on your furnace this season and notice it isn’t handling the comfort of the whole house and leaving cold spots, you’ll want that changed! In most cases, it will take work from professionals to restore the furnace to regular working order, or in more extreme cases, replace the furnace. 

Below we’ll look at some of the reasons you’ve got uneven heating in your home.

The furnace filter is clogged

You probably won’t need professionals to fix the furnace if this is the problem. The filter for the furnace needs to be changed at regular intervals of one to three months. If the current filter is clogged up because it’s been in place for too long, it will reduce airflow through the furnace. Less heated air will reach the room. Try a new filter to see if this fixes the problem. 

The thermostat is miscalibrated

You may have to look to the thermostat to find the culprit behind the misbehaving furnace. If the thermostat becomes miscalibrated, it will read incorrect temperatures in the house and shut off the furnace before it reaches your desired temperature. Pushing up the thermostat to try to get around this isn’t a solution, and it may damage the furnace. Let our technicians recalibrate the thermostat or install a new one.

There are blocked vents

If some rooms are colder than others, make sure the room vents haven’t been accidentally blocked with moved furniture or rugs. Sometimes people close vent covers because they believe this helps save money when nobody is using the room. Blocked vents not only restrict comfort in a room, but they can also cause damage throughout the HVAC system.

The furnace is improperly sized for the house

Is this a new furnace? Then the problem may be with how it was installed. A furnace must be sized so its heating capacity matches the heating needs of the house. A furnace that’s too small won’t be able to provide enough heat. One that’s too large will shut itself off early because it falsely registers that it’s met its temperature goal. An incorrectly sized furnace is a common problem if amateurs do the job. The only solution is to replace the furnace—and to have our experts do it so it’s the right size. 

The furnace is too old

On the other side of the age scale, you may have a furnace that is too worn down from age. One of the earliest warning signs of a furnace that’s starting to fail is when cold spots appear around the house: it means the furnace’s heating capacity is dwindling. The average service life expectancy for a gas furnace is around 15 years, so if your furnace is older than this, you may not need repairs, but a replacement.

You can count on us for fast furnace repairs in Indianapolis when you need them. We can also analyze your furnace to tell you when it’s best to replace it.

Call Vital Heating & Air because “Your Comfort Is Vital!”

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