Heat Pump Condenser Fan Motor Replacement Instructions

When the condenser fan on a heat pump fails, the entire heat pump ceases to work.

If the condenser fan is not fixed immediately, the compressor could burn out. The condenser fan moves air across the condenser to remove heat picked up from inside the building when the heat pump is in the cooling mode, and picks up heat from outside air when the heat pump is in the heating mode. There are very few repairs to be made to the condenser fan. The normal procedure is to replace it.

Turn the electric power off by pulling the disconnect out. Remove the access panel by using a screwdriver. Pull down on the panel to remove it.

Check for voltage using a voltage tester. Place the leads across two terminals of the motor starting relay where the two electric lines from the disconnect are screwed in. There should be no voltage present.

Remove the wires leading from the fan by sliding the slip off the terminals on the motor starting relay with a pair of needle nose pliers. Gain access to the fan motor. Access can be gained in some models by removing the grill over the fan by unscrewing it with a screwdriver, while other units require removing the entire lid by removing the screws and lifting it off.

Remove the fan motor. Some motors are screwed directly to the top, while others are mounted with a band around the motor. Removing the motor from a band requires loosening the nut in the middle with an adjustable wrench. Loosen the nut until the band is loose enough to slide the motor out.

Remove the fan blade by loosening the set screw in the hub of the blade with an adjustable wrench. Pull the blade off. Add a few drops of oil to the shaft and hub area if the blade will not come off. Wait twenty minutes and try again. Lock a set of vice grips on the shaft and hold it stationary while twisting the blade back and forth. Pull on the blade to remove it.

Check the motor to get the necessary information. Measure the diameter of the motor and the shaft. Read the data plate on the side of the motor to obtain the horsepower, RPM, amp rating, voltage rating, and the direction, clock wise or counter clockwise. Carry the old motor along to the parts house to be sure of a good match. Buy a new capacitor along with the motor.

Replace the old capacitor with the new one. Install the new motor if it is an exact replacement, sliding it into the band and tightening the nut on the band until it is secure, or if it screws to the top, attach it with a screwdriver. Push the wires into the control panel. Connect the brown wire to the fan terminal on the capacitor. Connect the other two wires to the two terminals on the motor starter relay, where the old wires were removed.

Check the wires on a universal motor. Locate the the designation of the wires on the side of the motor. Locate the common wire and the wire for the appropriate speed. Locate the brown wire that goes to the capacitor. Tape the ends of the other wires with electric tape. Roll the taped up wire into a neat package and run a band of tape around the bundle.

Check the two sets of wires at the back of the motor. Notice the two sets of wires are plugged together. Changing the set up of the plugs will reverse the direction of spin. Look on the motor and it will indicate the sequence of plugs for the proper direction.

Install the motor in the band or attach it to the lid with screws as the case may be. Connect the common wire and the power wire to the two leads on the motor starter relay. Connect the brown wire to the capacitor terminal marked fan.

Slide the fan blade onto the shaft and tighten the set screw with the adjustable wrench. Replace the grill or top of the unit and use screws to attach it. Turn the electric power on and check the unit.

Things You Will Need

  • Screwdriver
  • Voltage tester
  • Adjustable wrench
  • Wire cutters
  • Needle nose pliers
  • Vice grips
  • Electric tape
  • New motor
  • New capacitor

Tip

  • When installing the fan blade, the hub with the set screw always goes on the opposite side of the motor.

About the Author

Now residing in Hendersonvile, Tenn., William Misch started his writing career in 1994. His articles have appeared in the "Daily News" in Bowling Green, Ky., as well as newsletters for several national companies. Misch holds a Bachelor of Arts in journalism from Western Kentucky University.