Reefer Carrier Unit alarm AL25

[Gil Soares]

Dear sirs, good day.

I am repairing a Carrier reefer unit model 69NT40-511 that presents the alarm | AL25 (condenser motor protector ), which even after the engine has been repaired, the AL 25 continues. I have already tried to clear the alarm with the following sequence = Alarm List + AL25 Enter, but the alarm remains active (AA).

Would you have any tips to clear this alarm or teach me how can I reset the condense motor protector?

Thanks in advance.
Gilmar Soares

[frank]

Here is a link to the service manual. https://refcont.ru/files/pages/98/dc/93/T285.pdf

The AL25 Alarm is caused by the internal thermo protector going open circuit in the condenser fan. It is 'auto-reset' when the fan motor cools down.

If you look on page 7 - 3 the is a thermo link (P1 - P2) on the voltage line feeding the condenser fan. You can trace for an open circuit at this point.

If the internal protector won't reset then it will probably be a new motor required.

[Will]

To add...

While you study page 7-3, take note of the test points, marked "TP(1-9)" with a solid dot.
(also see page 6-19, figure 6-26 for TP location on controller)

With power disconnected, you can do continuity check between TP3 and TP4. This would test circuit from controller to internal protector on motor and back to controller.

So if you have repaired the motor and find those TP open, you may have wiring issues between controller and motor.

Edit; found a pic of TP on controller.