Lennox G61MPV Service Manual page 109

1 Disconnect power to unit. Wait 5 minutes for internal capacitors to fully discharge.
2 Remove three screws (figure 1) securing motor to control. Motor will now separate from control.
3 Disconnect three−wire motor to controller harness. See figure 2. If terminals are damaged replace
control.
4 Check the NTC thermistor for any damage. Replace the control if damaged.
5 Check the capacitors for any damage. Look for bulging or swelling caps. Replace control if caps
are swollen or bulging.
6 Check resistance between each of the three phase terminals in the control end of harness con-
nector. Resistance between any two terminals should be greater than 100K ohms. If resistance is
less than 100K replace the control.
7 If motor shaft spins freely in both directions go to step 8. If motor shaft will not spin freely in both
directions replace motor.
8 Check the motor side of the wire harness for any damage. If harness or terminals are damaged
replace the motor.
9 Check resistance between each of the three phase terminals in the motor side harness connector.
Resistance between any 2 contacts should be equal. If resistance between any 2 contacts are not
equal or or if any resistance shows open or short circuited, replace motor.
screw
screw
FIGURE 1
Verify Control / Motor Operation
(Emerson Motor Only)
capacitors (4)
screw
FIGURE 3
Page 109
motor to control harness
FIGURE 2
motor to control harness
NTC thermistor