Sure you can replace the relays, by yourself even. They are all pull out and push back in, without any screw or captive mechanism. Just make sure you get the right voltage and contact rating for the relays. Best way is to pull out the relays and see the ratings. All pretty standard items. The Cikachi floatless level switch is here

Edited to add : Have you checked that the metal rods in the tank are not corroded and sending back a correct water level signal to the CKC C61F-GP?


This post has been edited by stormer.lyn: Jan 5 2021, 11:54 AM

Lots of relay suppliers, doesn't have to be the exact brand. Usually the pin-outs of relays are standardised.Did the contractor check in the tank? The CKC item uses metal probes to sense the liquid level, and these have to send the correct signal for the circuit to work. Or maybe the CKC is the one faulty, and every time you change the selector, it resets.
You could swap the relays around, but I doubt the relays are the problem. You should confirm it by going to manual mode and then manually start and stop the motors with the "start" and "stop" buttons. Does it run properly manually? If it does, then the wiring and the relays are good. I'd look at the timing after that. I wonder what items LR and TD are for?

Any further thoughts I have will need me to go there with my meter(s) and start probing the circuit. Can't do that because although I'll have no job at the end of this month, I still have it right now! Anyway, good luck.

This post has been edited by stormer.lyn: Jan 5 2021, 10:14 PM