Unit keeps going on and off
28 Jan 2026 · 2 min
Your HVAC unit cycling on and off constantly usually means it's oversized and satisfies your thermostat too fast. This causes extra wear, higher bills, and leaves humidity in the air. Check for faults, inspect your ducts and insulation, and calculate your home's actual heating and cooling needs to size the system right.
Chapters
So starting and stopping is not good for the power of that unit. It's also not good for the unit. It's kind of like I talked about before, miles per gallon with your car. Obviously, it's more efficient for you to hop on the interstate and drive 8 hours than spend 8 hours in stop and go traffic. Right. You get better gas mileage out of the long trip. Your unit is the same way. So if it is cutting on and off, chances are the unit is too big for the home. And it's satisfying that thermostat very quickly and turn it right back off. It's getting cold or warm again, and then it's come back on satisfying coming right back off. So the challenge with that would be wear and tear on the unit, as well as running up your electric bill, because it's wasting energy. And when you get into the summertime, you're not dehumidifying the house properly. So you walk into some of these houses and, yeah, 75 degrees, but it feels kind of clammy and sticky. That's because it's not dehumidifying properly. So when it's, you know, 30 degrees outside or 90 degrees outside, for that unit to run all day is not uncommon. Okay. It's not gonna hurt anything. It's better for it to run longer than start and stop, start and stop, start and stop. Now, I would have a check it out is to make sure you're not having some kind of problem in the unit itself. But if the unit is okay, then you have to look at where it's at the home and the duct system as well. We tell our guys all the time, there's three aspects to a home. There's, you know, the unit itself. There's the envelope, which is the home. Is something causing this to happen? Did I change something? Did I change a window? Did I leave something open? Did or you missing insulation? You know, is something causing this to happen? And then you got your duct system under the house as well. So check all those things to make sure it's operating correctly. And if all those check out, then we have when you do a load on that house to make sure that you have sized for that house properly. And if it's too large, then we can fix it.
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