Slow fan motor

[Premium2000]

I have a one ton mini split ductless heat pump (Heat Controller Inc. MSH-012B). Recently, I started getting a main breaker trip (110v, 15A) after a few minutes of system operation.

It appears that the outdoor unit fan motor is running slow (330 rpm versus 800 rpm spec) and I have a fault code of a slow ( one flash every 3 seconds) flashing green light (LED91) on the evaporator's temperature control circuit board (PWB ASSY:6871AQ1050) . Perhaps without proper heat removal the compressor eventually exceeds the 15A breaker (normal current draw is 11A) and the unit shuts down to protect itself (thankfully).

I can't find the fault code list for this unit ( 8 years old) so I'm not sure if it is the motor or something with the control circuit. I checked the voltage to the motor and it reads 120v which should be fine.

I pulled the motor and it turns free, not signs of damage. I wire brushed the mounting surfaces just in case there was grounding issue but after reinstalling the motor the same problem persists.

To make matters a little more challenging, the one on-line source that I could find for a replacement motor indicates that it is not in stock. The motor is a LG 4681AR1392J.

Can anyone tell me what the slow flashing error code for this machine is telling me?

If it is the motor, does anyone know of a suitable replacement?

Thanks in advance for any advice!

Larry

[paul52446m]

I have a one ton mini split ductless heat pump (Heat Controller Inc. MSH-012B). Recently, I started getting a main breaker trip (110v, 15A) after a few minutes of system operation.

It appears that the outdoor unit fan motor is running slow (330 rpm versus 800 rpm spec) and I have a fault code of a slow ( one flash every 3 seconds) flashing green light (LED91) on the evaporator's temperature control circuit board (PWB ASSY:6871AQ1050) . Perhaps without proper heat removal the compressor eventually exceeds the 15A breaker (normal current draw is 11A) and the unit shuts down to protect itself (thankfully).

I can't find the fault code list for this unit ( 8 years old) so I'm not sure if it is the motor or something with the control circuit. I checked the voltage to the motor and it reads 120v which should be fine.

I pulled the motor and it turns free, not signs of damage. I wire brushed the mounting surfaces just in case there was grounding issue but after reinstalling the motor the same problem persists.

To make matters a little more challenging, the one on-line source that I could find for a replacement motor indicates that it is not in stock. The motor is a LG 4681AR1392J.

Can anyone tell me what the slow flashing error code for this machine is telling me?

If it is the motor, does anyone know of a suitable replacement?

Thanks in advance for any advice!

Larry

Does that motor have its own start capacitor? If its a bad capacitor the motor will run slow like that. You might have to check with a dealer for a motor replacement. Later Paul

[Premium2000]

Thanks Paul.

The unit does use a dual run capacitor rated at 6/45uF @ 370/400VAC.

While it does not show signs of damage, it seems like the mostly likely source of the problem.

I can't seem to find an exact replacement. There are dual run capacitors rated at 5/45, 7/45 and 7.5/45 (370V or 440V). Can I use one of these? If so, which rating would be the best suited?

Thanks,

Larry

[paul52446m]

Thanks Paul.

The unit does use a dual run capacitor rated at 6/45uF @ 370/400VAC.

While it does not show signs of damage, it seems like the mostly likely source of the problem.

I can't seem to find an exact replacement. There are dual run capacitors rated at 5/45, 7/45 and 7.5/45 (370V or 440V). Can I use one of these? If so, which rating would be the best suited?

Thanks,

Larry

I don't know about using a different capacitor, i always order
up the right one if i don't already have it it my service truck. Later Paul

[Premium2000]

Thanks,

I think I found a supplier with a direct replacement. Hopefully, that will solve the problem.

Larry