Central Air Conditioning Problem

Is your central air conditioning problem a totally dead unit?

If your air conditioning system is a split type with DX (refrigerant cooled) or chilled water air handlers inside the building, and they're not running, find the temperature controllers and motor controllers that control them, and verify that they are turned on, and that the circuit breakers are not tripped or turned off.

If a breaker has tripped or there is an alarm indication, you should have a technician troubleshoot and correct whatever caused this central air conditioning problem.

If the temperature control is programmable, verify that it is programmed to be in the cooling mode.

If the temperature control is digital, and it's blank:
there's no power or the batteries are dead, so you'll need to take care of that first.

It's also a good idea to verify that the supply voltage to the air handlers is correct.

If the voltage is too high, too low, or if you've lost one line, a good voltage monitor will keep your air handlers off.

Is the air conditioning in your building totally controlled by a central control panel?

Your central air conditioning problem might be that the area or zone you're concerned about is not programmed for cooling for some reason.

The timer might be out of calibration, or someone may have made a programming error.

A good control panel and program can also indicate the cause of your central air conditioning problem.

If your indoor air handlers are running but not cooling, or if you have a package type central air conditioning unit that's totally dead, check the breakers for the condensing unit or package unit and verify that they are not off or tripped, and verify that the disconnects are not turned off.

If the temperature control is on to cool, and the breakers and disconnect are on, but you're still getting no cooling, you'll need to have a technician troubleshoot your central air conditioning problem.

If the breakers or disconnect are turned off, you need to find out who turned them off.

If they were left off accidentally, and there is no maintenance or repair work being done,

first, you must verify that no one is working on any of the machinery that will be energized,

and then turn the breakers and disconnect on.

After a time delay, if there are no other problems, the unit should run and cool normally.

If the main circuit breakers for your central air conditioning unit are tripped, have a technician troubleshoot the cause.

If the problem with your unit is that it's freezing up, you might find a solution on our Air Conditioning Freezing page.


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