This is specific to model WH2903A but will likely work for other, similar models.
When I first installed this cooler, it worked fine. After only about 60 hours of use, it began to sound terrible, like the motor had a failed bearing or bushing. For the first 13 seconds of the video, only the water pump is running, and it sounds fine. After that, both the water pump and blower motor are on.
With guidance from Robert, a manager at PMI, I was able to fix the problem by returning the blower wheel (squirrel cage) to its correct position so that it was no longer rubbing against the housing. To do this:
1. Remove the pad holder to gain access to the inside of the unit.
2. Determine if the blower wheel is rubbing on the housing. If so, proceed.
3. Remove the set screw locking the blower wheel to the blower shaft.
4. Slide the blower wheel back into the center of the housing and re-secure the set screw. If the blower wheel will not slide, proceed to step 5.
5. Use a pair of Vise-Grips (or other locking pliers) to lock onto the blower shaft.
5. While holding the blower wheel steady, turn the shaft with the Vise-Grips until the blower wheel “screws” back into the correct position.
6. Make sure the flat side of the shaft is aligned with hole for the set screw.
7. Reinsert and tighten the set screw.
Post time: Jul-13-2017