[RB855]

Have been following this for a while now (just in case my chinese heatpump waterheater controller ever failed), and while working on a window shaker the other day something occurred to me. The unit I was repairing had a failed relay board. This board contains all in one many of the components mentioned early on in the thread. It has 3x 25amp relays, 4x 3amp relays, 5v filtered regulated power supply (minus off board transformer), relays are opto-isolated, has a little piezo beeper, and 3 removable temp sensors (1x tube sensors, 2x air temp) with onboard filtering. And this whole board as it sits only costs about 22$ Now, as I mentioned this board had failed, but the 6 I have here in front of me, every single one only has a bad filter capacitor on the 5v supply, an easy fix! The boards I have on hand are Amana 30132023 , which lack 1 of the 3amp relays, but the 30132033 has the most relays, and actually costs less... Since these are all warranty change outs and were heading for the trash, if there is interest in toying with one of these, pay the post and its yours!

I should mention, originally the 4 small relays were for reversing valve, low-med-high fan speed. The large relays, 2 were used for the heat as a redundancy and 100% isolation from mains, and one for the compressor (the top pin on this relay supplies L1 to the board through a 3.15a fuse, L2 is on the board itself, that has a pinout for the xfmr and runs the fan/rvalve outputs). One of the air temp sensors was inlet, one was outlet, and depending on the model the tube sensor was mounted to evap or condenser. There is a model board out there with both, but i forgot which one it is.
Also note worthy, Amana 30132030 has a 5th 3amp relay used for vent swing motor, and uses 4 sensors, and uses a different form factor, otherwise the same as above.