WHP Catalyst wonky recirc valve

[kb0nes]

Did a bit of digging on the board itself. I managed to find a tiny photo of the bottom of the PCB so I could follow the traces.

The IC that feeds the 2nd pin from the left on the connector is U10, the center one closest to the board edge. Pin 6 feeds the connector. You could measure AC voltage on this pin during operation, it should drop near zero when the solenoid coil is not energized. Pin 4 should be AC hot all the time.

The IC itself is common, you can get them at most any electronics house, Digi-Key, Mouser, Newark etc.

 

[thefixer]

The 6 optocouplers are used for the other 6 valves in the washer (bleach, fresh, fabric softener, detergent, hot, cold). The diverter valve receives power via the outboard relay above the transformer.

 

[thefixer]

Here's the circuit trace for pin 2

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home.comcast.net

 

[thefixer]

Actually, it's pin 9 of connector P6

 

[kb0nes]

Hold the presses, indeed my board orientation was in error!! I hate working without a board in hand. Thanks to ?? (thefixer) for the clear graphic!

So the solenoid is relay driven. That makes more sense as it looked to be a bit substantial for those Triac driver opto's to drive. This should make the troubleshooting easier, although a bit more puzzling. Relays are less likely to leak. Hmm

 

[thefixer]

kb0nes, the pin you are refering to is for the tan/red wire, not the wht/red wire. tan/red is pin 2, wht/red (diverter valve) is pin 9.

 

[thefixer]

Relay pin-out bottom view, pin 3 output to diverter valve

 

[DADoES]

 
Whew.

OK, so the relay should be either on or off, no current leaking.  Perhaps the relay is sticking?

Maybe the valve/solenoid is somehow the fault?

The new valve assembly arrives tomorrow, I can connect the wires without mounting it and hoses for a quick test.

 

[kb0nes]

Yes the relay should be either on or off. I can't really see a failure mode where it could "leak" though. I'd want to check to make sure that the relay coil wasn't staying energized when it shouldn't be. Something further back on the control board may be the failure.

If indeed the relay is bad it is an easy thing to swap out, Google the part number and you will find them if you need a replacement. This is a similar relay I have replaced on a few furnace boards.

 

[combo52]

Two-Way Valve

Great discussion Guys, these TWVs do have a 120 volt A/C solenoid coil, it is the same valve and coil that was used on the non-electronic Catalyst machines and on the WP=KM Resource-Saver DD Washers.

 

Foot note for WP & KM 29" Combo restorers, the valve part of these TWVs works perfectly on these combos.

 

[tomturbomatic]

The newer valve works much better than the older combo diverter valves which used a pot metal flapper inside the valve. The new ones have a plastic flapper that does not corrode away. The little stem of the flapper used to break off and, while the valve solenoid would snap like it was working, it could not because of the broken flapper.

 

[DADoES]

 
Interestingly ... fortunately ... thus far on testing (three spin-only cycles) ... the new valve does not hang.

Yay.

 

[DADoES]