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Serving the Greater New Braunfels, TX Area

Serving the Greater New Braunfels, TX Area


Your Air Conditioner Problem Might Be the Thermostat: Here’s Why


When you can’t get your home cool in Texas, it can be a huge problem that needs to be addressed right away. But sometimes, it’s not the air conditioner that’s having trouble. It’s possible that the real culprit is your thermostat. If you can’t get your air conditioner to properly cool your home, here are some things you should check before you blame the AC unit itself.

Is the Thermostat Set to ON?

Of course, you imagine that it’s on. You never turned it off! But an accidental shoulder bump or a mischievous child or pet could have completely turned the thermostat off, and stopped it from sending any information to your air conditioner. 

Is the Thermostat Set to COOL?

Similar circumstances can cause the switch on your thermostat to be flipped from the cooling setting to the heating setting. And on a toasty Texas summer day, when no heat will be called for, that’s essentially the same as having it turned completely off.

Is the Thermostat Set to FAN ONLY?

With the fan running, you may think you hear your air conditioner. But if it’s just the fan, and the AC unit’s compressor is never kicking on to circulate refrigerant and carry heat out of your home, you could have a perfectly functional air conditioner and a completely overheated house.

Is the Thermostat Programmed Correctly?

Modern thermostats can be programmed for many things. If your thermostat mistakenly believes you are not home because of a setting being accidentally turned on, you could have a too-hot house but no air conditioner problem. If your thermostat was in your home before you moved in, you might not even be aware of the settings the previous residents programmed in. Keeping air conditioning to a minimum when away from home saves a lot of energy and money, but if those settings are mistakenly triggered, you could end up sweltering.

Do the Batteries Need Changing?

If there’s no display at all on your thermostat, try changing the batteries. Even if the display hasn’t completely failed, dying batteries can fail to send signals from the thermostat to the air conditioner. Replacing batteries is much quicker and less expensive than a repair, so it’s worth a try.

Is the Thermostat in a Bad Location?

If you haven’t lived in your home for long, or if your thermostat was installed relatively recently, it could simply be that the location is not ideal. If the thermostat is in an area that gets colder than the rest of the house, such as near a drafty door or an air conditioner vent, or warmer, like too close to the oven or in a spot that gets hit by direct sunlight, it won’t give accurate readings. It will send information to the air conditioner… the wrong information.

Is the Thermostat Malfunctioning?

Sometimes, thermostats simply need to be recalibrated. This is like reminding them of their baseline, similar to zeroing out a scale. But sometimes there is an electrical issue, such as a loose wire. If none of the other suggestions have resolved your problem, a technician in AC repair in San Marcos, TX can determine whether the thermostat or the air conditioner is at fault. 

At Thayer Air Conditioning, your comfort is our #1 priority! Contact us today.

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