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Three Reason Your Air Conditioner Is Not Blowing Cold Air

It has been a long hot day, and you arrive home from work.

It feels warmer than usual in your house. You check the thermostat, and it reads 78 degrees.

You know something must be wrong. The fan is working, and the air is coming out of your vents, but the air is not cool.

What could be the problem?

Clogged filter

One reason your AC unit could not be cooling is the air filter is clogged.

Every 3 to 4 months, you should replace your filter.

Similar to an oil change, your AC unit needs to be serviced just the same, and replacing your filter is part of that.

When the filter becomes clogged with dirt or debris, the unit can not filter the air properly, causing it to have to work harder.

The air will not be as cold or clean as it would if your air filter is replaced.

So, if your AC unit is blowing warm air, try replacing your air filter first.

Low on refrigerant

Your AC unit blows out cold air using a gas called refrigerant there are currently two refrigerants that are used in AC units to help them cool your home down.

Over time the refrigerant levels can begin to drop and not blow out cold air.

Once the refrigerant levels drop too low, the ac unit will freeze up outside and cause only warm air to be produced.

When this happens, a technician will need to come out and fill up your AC unit with new refrigerant and top if off.

In no time you will have cold air blowing again.

At Guardian Heating & Air Conditioning, your safety and security are our top priority, call us today at (303) 952-9047 to schedule an appointment today.


A sure way to ensure that your AC unit will be blowing nice cold air all summer long is the have maintenance done on it at the beginning of the season.

A 21-point inspection will have a technician look over all the working parts of the ac unit and make sure all the refrigerant levels are topped off and check the filter to make sure it is clean.

After the maintenance, you are sure to have a cool running system all summer long.

Guardian Heating & Air Conditioning has been around in the industry for years. We have been trusted by hundreds of customers looking for heater repair service Centennial CO. Give us a call at (303) 952-9047 to get your issues solved today.

” I have done business with Kurt for over 15 years, he is one of best HVAC guys out there. He is very responsive, his prices are fair and always tries to save the customer money.”

Paul N.


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