Anonymous asked in Home & GardenMaintenance & Repairs · 1 decade ago

Home A/C is running a lot?

We keep our A/C on all the time. During the day we set it at 78 & at night drop it down to 76. It seems like the air has been running a lot lately, even at night when everything should be cooler. Last night, the outside temp was about 85 Degrees F & it ran for about 2 hours straight. Would a bad thermostat cause this to happen? We've even tried setting it at 80/85 & it does the same thing.

The unit is about five years old & is a Train. What else could be the problem?


New Roof with plenty of vents

3 Answers

  • smokey
    Lv 7
    1 decade ago
    Favorite Answer

    if the house does not have attic ventilation the heat builds up there and causes the A/C to run longer.

  • 1 decade ago

    The easiest thing you can do to help out your system is to keep the return air filter changed every 30 days, and keep the evaporator coil CLEAN. Reduced airflow & heat transfer capability robs your system of its cooling capacity, drastically lowers efficiency and in the end, wastes electricity & money.

    The unit being 5 years old its time for a cleaning....and at least a refrigerant pressure & performance check. The typical evaporator operates at 40 to 45F. If yours does not, it should.

    There are several no-rinse "scrubbing bubbles" type cleaners available at most every HVAC supply house and perhaps even home improvement stores. For heavy gunk and households that smoke and/or have animals, a long bristle brush and a good soaking of Clorox Cleanup will work wonders. The clorox must be rinsed off. Do not apply straight bleach to the coil as it is slightly acidic to the fragile fins... The inside fan (squirrel cage) can even get caked with dust and not move air like it should.

    Next, go outside and clear the outside (condenser) coil of any debris.... take a hose and spray it out. You should be able to see he water spray on the inside of the unit....

    These measures should help your unit be all it can be...

  • ?
    Lv 5
    1 decade ago

    You mean Trane?

    Something is affecting the efficiency of the unit for it to have to run that much. Check the temperature of the air being supplied to your room and compare it to the air going to the return. The difference should be more than 10 degrees, closer to 20. If not then you will need service (low refrigerant, weak condensing unit fan, clogged condenser coil, broken duct).

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