Electrical problem with spot free

[Mchas]

My spot free decided to stop working today. After probing around with a voltmeter it seems like one of these resistors (? Edit: googling the markings, might be “bridge rectifiers” whatever that is?) might be the issue. I am getting 24v on the left side but nothing on the right side when it goes to the relay (?).

Could one of these have gone bad? Is this a common setup? Seems kind of “home grown” to me - there must be a better way to do this?

Including a picture of where I think the problem might be. Didn’t think to take a zoomed out picture showing the rest of the components. Also including a picture of the cover to the relay that this leads to

Any thoughts are appreciated!

 

[Mchas]

Is this a poor man’s version of something like an IDX MX10 controller?

 

[MEP001]

Is this a poor man’s version of something like an IDX MX10 controller?

Sort of, more like a clone of Specialty Equipment's "diode box" that converted the 24VAC to 24VDC to power a DC relay. FWIW I've seen a lot of failures to IDX's multiplexers even though it looks like a better design and a little easier to work with. I use the GinSan one, which are about the same price. I wouldn't ever place the load of a spot free pump directly on the controller.

 

[Mchas]

So what would be the right way to wire this up to get it working again?

 

[MEP001]

If you use a multiplexer, the easiest way to get the load off the device is to use a heavy relay or contactor with a 120V coil, run the line side of the power for the pump through the device to the coil, and wire the multiplexer per its instructions. You could even use a bank of relays instead of a multiplexer, but I like to have a delay on the pump which both IDX and GinSan multiplexers have.

 

[$!cmad3k]

Reminds me of whats in a futura ro control box

 

[MEP001]

Reminds me of whats in a futura ro control box

Because Futura is from Specialty Equipment who derived their "diode box" from the method used in OP's setup.