Tip & How-To about Heating & Cooling

How to fix problem of Air conditioner doesn't turn on

If your central air conditioner doesn't go on automatically:
1) Be sure the thermostat is set to “cool” and that the set temperature is well below the ambient temperature.
2) A central air conditioner should be on a dedicated 240-volt circuit; check the main electrical panel and any secondary circuit panels for a tripped breaker or blown fuse. If you find the problem there, reset the breaker or replace the fuse.
3) Make sure the furnace power switch is turned on and that the outdoor condenser's power switch, which is mounted on the outdoor unit, hasn't been shut off. Also, be sure the 240-volt disconnect next to the compressor, which is in a metal box, usually mounted on the house wall, hasn't been shut off.
4) Turn off the power to the air conditioner and check the thermostat.
5) Remove the thermostat's cover and unscrew the wire from the Y terminal.
6) Turn the power back on.
7) Holding the wire by its insulation ONLY, touch the bare end to the R terminal and hold it there for about two minutes. If the compressor kicks on, the thermostat is faulty; replace it or call an air-conditioning technician. If the compressor doesn't go on when you hold the two wires together, turn the power back off and call a technician.

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series 48000 with heat pump we don't want this to run all the time will the heat shut off when it reaches a certain temp also if the power goes out does it come back on automatic we want to heat our place when we go away


Not sure about your particular make and model, but air conditioners are designed to work with a thermostat to control the functions. A properly functioning thermostat will stop the compressor when the set space temperature is satisfied. When the space temperature falls below (heating) the set temperature, the thermostat should turn it back on. In the event of power failure, an electronic thermostat probably will not operate at the previous set temperature when power is restored, but maybe at a higher temperature (but will work).

Dec 05, 2013 | Coleman Mach 15 Air Conditioner

1 Answer

Daughter moved into apartment and Goodman wall unit not cooling, no service till Monday. Blows air, just not cool. Anything I can do?


Make sure that the cooling control or thermostat is set below the ambient room temperature by at least 4 degrees. It may be a case that it was not set low enough to cause the compressor to turn ON. Only the fan is working.

If that doesn't help solve the problem, invite her to stay with you until Monday.

Thanks for choosing FixYa.

Aug 06, 2011 | Goodman Heating & Cooling

1 Answer

our luxpro 511Lc air conditioner thermostat doesn' go on & off automatically


Hello,
I am afraid you will have to replace the thermostat. From the look of things, the thermostat is defective and needs to be changed.
Follow the information on the below link on how to replace/change your AC's thermostat.
Click here: http://www.central-air-conditioner-and-refrigeration.com/Ac_thermostats.html
Keep me posted if you need any more help.
Regards.

Jul 11, 2011 | Heating & Cooling

1 Answer

airconditioner turns on and off automatically.


It is normal for an air conditioner to turn off and on automatically. This keeps it from making the room too cold. If it has a digital thermostat, set the thermostat to what temperature you want it to be in the room. If the air conditioner has a knob that says "colder", you let the air conditioner run until the room is comfortable to you and then you turn the knob very slowly toward warmer until the air conditioner turns off, and then very slowly turn it back to colder until the compressor comes back on. It's normal for a non-central air conditioner to run the entire time you have the power turned on but the compressor, which provides the cooling, will turn on and off when only when cooling is needed.

Sep 20, 2009 | Samsung AW0603B Air Conditioner

2 Answers

central air conditioner doesn't turn on... Any suggestions?


If the compressor turns off and won?t come back on during a very hot day, the unit may have built up a high "head" pressure and the high-pressure limit switch may have tripped. This is usually located right inside the access panel on the compressor unit. Simply push the button to return it to operation. If your central air conditioner doesn't go on automatically: 1) Be sure the thermostat is set to "cool" and set below room temperature. 2) A central air conditioner should be on a dedicated 240-volt circuit; check the main electrical panel and any secondary circuit panels for a tripped breaker or blown fuse. If you find the problem here, reset the breaker or replace the fuse. 3) Make sure the furnace power switch is turned on and that the outdoor condenser's power switch, mounted on the outdoor unit, hasn't been shut off. Also be sure the 240-volt disconnect next to the compressor (in a metal box, usually mounted on the house wall) hasn't been shut off. 4) Turn off the power to the air conditioner and check the thermostat. 5) Remove the thermostat's cover and unscrew the wire from the Y terminal. 6) Turn the power back on. 7) Holding the wire by its insulation, touch the bare end to the R terminal and hold it there for about 2 minutes. If the compressor kicks on, the thermostat is faulty; replace it or call an air conditioning technician. If the compressor doesn't go on when you hold the two wires together, turn the power back off and call a service technician.

Jan 18, 2006 | Haier Energy Star ESA3183 Air Conditioner

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