If you're having trouble with your central air conditioner turning on automatically please go straight through the following steps.
1) Set the thermostat to "cool." Check that the displayed set climatic characteristic is well below the current climatic characteristic or the real climatic characteristic of the room.
2) Your central air conditioner should have its own dedicated 240-volt circuit. Locate the main electrical box (or panel) commonly located on one of interior stable walls. Check for a tripped breaker or a blown fuse. If the air conditioner breaker is tripped or blown, reset or replace the fuse.
3) Check that the furnace power switch is in the on position. Next, look for a switch mounted on the outdoor unit. This is the condenser's on/off switch. Make sure that it's off. Now, make sure the 240-volt which is next to the compressor (it should be in a metal box typically located on the covering house wall adjacent to the unit) is still on.
4) Make sure the power to the air conditioner is off. Now, check the thermostat. Take off the covering housing on the thermostat. Unscrew the Y concluding wire and turn the power back on.
5) Now we accomplish the tests. Grab the wire by its rubber covering. Do not touch the metal with your fingers. Take the metal exposed quantum of the Y wire and hold it to the R concluding for a join minutes. If the compressor turns on, you have a faulty thermostat. Call a technician. If the compressor does not kick on, turn the power off and call a technician.
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