Haier HPE07XC6 portable air conditioner

[CoolFish]

Found a Haier portable air conditioner with a board issue. There are 2 boards, one on top with the display and push buttons, and the other down low with the relays and transformer. The indoor fan runs like normal, but the Compressor, outdoor fan, and water motor don't kick in when there should be a call for cooling. If I bypass the relay on the bottom board the compressor and motors run and it cools well. Does anybody have any suggestions on how to determine which board is not working? The transformer on the bottom board is working, but I don't have the output voltage (12v) at what I am assuming is the coil side of the compressor relay. If I were to guess, I would guess the top board is not giving the bottom board the call for cooling. Any idea's on how to verify my guess before I drop the money on a board?

Thanks,

Mike

[appl.tech.29501]

Can you program the user interface board properly? all the buttons work?

If you bypassed the relay on the control board and the compressor came on then the board is bad. Probably a sensor that is actually bad, but they come with the board.)

Control Board Link

[CoolFish]

Yes the interface board buttons all work, can switch modes and change fan speeds, all the lights work. I set the set point to 72, it shows 82 (correct temperature)  as the temp in my garage. Just no compressor. Bypassing the relay on the bottom board tells me that the compressor works. Now, if I had control voltage on the coil side of that relay, I would say, absolutely, relay is shot, board is shot, no problem, but since I don't have control voltage to that coil side of the relay, I'm wondering why not. Is it something in the top interface board not sending down the control current to close the relay, or is it something in that bottom relay board? Since the thermistor is the only real sensor involved, and it seems to be displaying the correct temp, I've kind of eliminated that from my thought stream.

I'm thinking that there should be a way to tell if I'm getting current through that interface board, if only I knew what I could expect to see on the ribbon harness. I'm still kind of leaning toward it being an issue with the interface board, but would like to have a way to verify.

I worked on a GE window shaker a while back that was about the same deal. I flipped a coin and replaced the relay board, turned out to be the interface board. There has to be a better way than just trying a new part.

[appl.tech.29501]

you could verify voltage through the harness for the display board if you could find a schematic for it (which is virtually impossible). there looks to be 2 sensors on that unit. you can try heating the one on the evaporator up with a hair dryer or other device...sometimes when they are faulty that will make them work..if the compressor come on then you know the power board is bad.

[RegUS_PatOff]

do any of the other Relays work (have Coil  DC voltage) ?

does the Transformer Primary & Secondary Windings have AC voltage ?

 

[CoolFish]

Yes, AC voltage is present and correct on the primary and secondary of the transformer on the bottom board and the indoor fan motor starts on a call for cooling or from turning on the fan. Haven't checked the voltage on the fan relay coil, so I'm not sure if that is DC, I'll have to check later when I get a chance to play with it again.