The blower in your air conditioner is what pushes cool air through your house. When the blower doesn't work, your home won't cool down. Several things can be to blame when your house isn't chilling down, so the first step is to determine if the blower is at fault. Here's how an air conditioning repair technician might test your blower for an electrical malfunction and repair problems they find.
Turn the Thermostat to Fan Only Mode
By shutting off the AC setting and turning the thermostat to fan mode, the blower should start up while the rest of the AC stays off. This lets the technician know if the blower is malfunctioning or if the AC has problems in the condenser or refrigerant lines. If the blower fan doesn't run, then the repair technician can start testing blower parts.
Perform Electrical Tests
Besides the blower motor, the blower is controlled by a capacitor, wiring, and a relay switch. There could be a problem with any of these parts, so the technician has to isolate the cause. They can do this with a multimeter. The meter can be placed on the capacitor, wiring, and relay to find out where the flow of power stops.
If the problem is with the wiring, a wire may need to be tightened or replaced. If the capacitor is bad, the capacitor might need to be replaced. Sometimes a capacitor can look damaged and provide further clues that it's to blame for the malfunction.
Wiring connects the capacitor to the relay, so if the wiring and capacitor test fine, then the problem might be a bad relay. The air conditioning repair technician can test the relay to make sure. If it's found to be bad, then the relay can be replaced with a new one.
Check the Door Safety Switch
Testing the electrical parts in the air handler is essential for finding the reason the blower isn't working. However, testing the electrical components is dangerous. Your AC probably has a door switch on it for this reason.
When the panel on your air handler is removed, the switch pops out and kills the power to the blower. The repair technician checks the switch to make sure it's functional for safety reasons, to make sure it isn't broken, and to see if it's the reason for the lack of power to your blower. If the switch isn't working properly, it's easy to replace it with a new one.
These electrical parts are common reasons for a blower malfunction, but they aren't the only things that can keep your blower from working. The air conditioning repair technician may also need to check the motor, blower cage, thermostat wiring, and control panel to get the blower back in service.
For more information, contact an air conditioning repair company in your area.