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HomeRepair HelpGarrison Central A/C RepairGarrison Central air conditioner won't turn on Repair
Garrison Central air conditioner won't turn on
If your Garrison central air conditioner won't turn on, the problem is usually in the low-voltage control circuit that signals the outdoor condensing unit to start. The most likely cause is a failed transformer, which supplies the 24 volts needed by the thermostat and contactor. Next, a defective furnace control board may prevent the contactor from receiving its 24-volt signal or stop power from reaching the blower motor. If the thermostat display is blank, replace its batteries, then check for an incoming power problem, including a tripped circuit breaker, blown fuse, or turned-off service switch at the furnace or air handler. Less common causes include a failed wall thermostat or thermostat wiring, faulty thermostat wiring, or a contactor that is not closing. You can inspect batteries, switches, fuses, and thermostat settings safely, but testing a transformer, control board, contactor, or 240-volt circuit requires electrical experience and should be handled by a qualified technician. Enter your Garrison central air conditioner model number to find the exact replacement transformer, control board, thermostat, or other part for your specific unit.
01 - Garrison Central Air Conditioner Transformer
The furnace control board sends a low voltage signal of 24 volts to the thermostat. When the themostat cooling contacts close, a 24 volt signal is sent to the contactor coil, closing the high voltage circuit and sending power to the condensing unit components. Some furnaces have a separate transformer for the 24 volt circuit, so if the contactor is not receiving the proper voltage when the thermostat cooling contacts are closed, it's likely this transformer has failed and the component will need to be replaced.
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Highly Likely
02 - Garrison Central Air Conditioner Control Board
If the central air condensing unit contactor is not receiving 24 volts or power is not getting to the furnace blower motor, a possible cause is a defective furnace control board. While this is not a common problem, if all other potentially faulty components are working properly, the control board should be replaced.
Highly Likely
03 - Wall Thermostat Batteries
Most wall thermostats are either powered by an enclosed battery or by the furnace or air handler transformer. If the thermostat display is dead, you can remove the thermostat cover and look for replaceable batteries. Replace the batteries if needed and check operation.
Common
04 - Incoming Power Problem
Check to see if there is power to the furnace or air handler. One or more indicator lights on the control board should be illuminated. If there is no power to the furnace or air handler, check to see if a circuit breaker has tripped or a fuse has blown. Confirm the power switch on the side of the unit is turned on.
Common
05 - Garrison Central Air Conditioner Wall Thermostat
The furnace control board sends a low voltage signal of 24 volts to the contactor through the wall thermostat. When the contactor receives the signal from the wall thermostat, it closes the circuit, sending voltage to the condensing unit components. There should be 24 volts between the common (“C”) and yellow (“Y”) thermostat wire terminals on the furnace control board when the wall thermostat is in the cooling mode. You can check for this voltage with a multimeter. If voltage is not reaching the contactor, it's likely the wall thermostat is defective and will need to be replaced.
Less Common
06 - Garrison Central Air Conditioner Wifi Thermostat
The furnace control board sends a low voltage signal of 24 volts to the contactor through the WiFi thermostat. When the contactor receives the signal from the WiFi thermostat, it closes the circuit, sending voltage to the condensing unit components. There should be 24 volts between the common (“C”) and yellow (“Y”) thermostat wire terminals on the furnace control board when the WiFi thermostat is in the cooling mode. You can check for this voltage with a multimeter. If voltage is not reaching the contactor, it's likely the WiFi thermostat is defective and will need to be replaced.
Less Common
Frequently Asked Questions
Why is my Garrison central air conditioner not turning on?
How do I know if my Garrison AC thermostat is not working?
What should I check if the outside AC unit is not turning on?
Could a transformer or control board keep my Garrison air conditioner from starting?
How do I identify the correct replacement part for my Garrison central air conditioner?
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