Attic Fan Motor Not Working High Speed

Does the speed switch look like the silver handle coming out of the plate.

Attic fan motor not working high speed.

If this fan has a timer and or a variable speed switch repairs are sometimes possible if the fault lies in one of the switches and not the motor. Blower resistors are made of. The blower resistor is connected in series to the blower fan motor. Remove the outer casing of the attic fan and check to see if the belt is sagging cracked worn or broken.

You can fix this issue by turning down the settings or checking that the fan is getting enough air. If there is any damage to the belt replace it with a new one. Attic exhaust fans power ventilators we usually simply replace the entire unit. These are the common causes.

This means that the current running through the blower motor and its speed is therefore controlled by the resistor value. The user chooses a fan speed by selecting a speed which then connects one of the resistors in the blower resistor pack. If it is rotating slowly or not producing a lot of air in the high speed setting you may have a problem with the exhaust or intake. Your attic fan may not be turning on because of an electrical problem like a tripped circuit breaker a blown fuse or a bad connection.

Attic fan not turning on. Repairs are generally impractical. If the attic fan isn t turning on it could be an electrical issue a problem with the thermostat or the motor of the fan that s not working. Little or no airflow.

Look at the circuit breaker or fuse box to see if a switch has flipped. If this doesn t fix the problem a burned out fan motor may need replacing. Other possibilities include damage to the wiring or a switch best repaired by an electrician. When running at a high speed setting does the attic fan run hard or sluggishly.

Attic fans can sometimes start making noise whether it s humming rattling or making some other annoying noise. It selects one fan winding for slow or the other for high. Parts can come loose or erode from high amounts of fan usage while turning the speed up to high can cause a persistent loud hum. If the motor is working but the fan blades are not moving the problem may be the belt.

If this is not your issue the next thing in line is the high speed relay mounted on the front of the hvac box behind the accumulator.