Here’s your scenario: you’re working on a Whirlpool CAM2742TQ2 Washer, and you’ve determined that the auto temp control (ATC) has failed such that it won’t energize the water valves and allow the machine to fill. You intend to replace the ATC, but it’s on backorder. Is there any clever trick you can think of that will at least get the customer going temporarily while they wait?
Time to crack out the schematic.
It looks like there’s a lot going on here, what with all those alphabetically labelled switches that the ATC controls. But what if we could just bypass all that? Let’s look at how, with just a couple jumpers, we can rig this circuit to run whenever timer contacts 11 (for main wash) or 12 (for rinse) are closed.
There we go — that’s all we have to do! Those two red lines are just jumper wires, and that orange X is showing where we disconnected a wire.
The jumper directly to the left of the water valves means that, whether it’s contact 11 or 12 that’s closed, both valves receive power. The other jumper is there to completely bypass switch A in the temperature switch assembly. As for disconnecting the wire from terminal 5 on the temperature switch, that’s just there to completely take the switch out of the picture.
Here’s a markup of how the valves’ power supply looks with contact 11 closed. You can figure out for yourself how it would work with contact 12 closed instead.
What are the consequences of this arrangement? Well, obviously the ATC has been taken completely out of the picture, so there won’t be any automatic adjustment of the fill temperature. Furthermore, whenever the machine fills while rigged up like this, it will fill with warm water, since both valves will receive power. But that’s just fine for our purposes, since this is a jury-rig to help the customer limp along until we get a replacement switch. As a bonus, you have definitely proven that the ATC switch has failed so you know for certain that the new switch will fix the problem.
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