HVAC - Mini-splits - Gree Multi42HP230V1C0 Troubleshooting

[rpaoness]

Still running on the “repaired” old board. Baker agreed to take the bad new board back and ship a replacement.

[kevm14]

I guess you need to at least have a working replacement board on hand and then when you decide you are finished milking the old one you can pull it from the shelf and put it into service. Unless you think that solder joint was the issue.

[rpaoness]

I do think the solder joint and fried mouse were likely contributing. Initial startup with the "repaired" old board still had E6 on the C-channel indoor unit. It wasn't until reattempting hours later that it was OK. I'm concerned about even turning the unit off and back on while we're relying on it to keep the house comfortable with current temps and humidity since it might not restart. The house did overall stay OK with the 36k unit in the dining room/kitchen, but it seems to be hard to get the tenants to live with doors open. I would like to have a new board in hand before I touch it again if I can. The $155 is inconsequential - I really hope I can get the unit back to reliable.

[kevm14]

My tenants are trained (mostly) that the doors stay open at least during the day. 50% of my mini-split capacity is via bedrooms. At night I let the great room unit drop the house a couple degrees so it is "reset" for the next day. Peak furnace thermostat temp was like 74 and only briefly. The humidity is well under control so that temp is perfectly comfortable. Replacing the master bed window unit with a 9k head would probably turn that occasional 74 into a 73 max (maybe 72) and then adding another ~12k to the living room would give me 72F across all areas of the house no matter what. I'd probably have to turn that unit off a lot of the time since they will cool down ~3F past setpoint at min throttle before finally cycling off.

[rpaoness]

New board came in, but 0 issues/codes since the last startup. I guess I'll just run the old one until it has a symptom again...

[rpaoness]

Still running without issue...

[rpaoness]

After 8+ years I finally installed my last indoor head in the basement yesterday. Seems to work fine. I sort of wanted to wait until codes had not reappeared so I wouldn't be troubleshooting a new install at the same time I still had an intermittent issue. Seems to be fine so far.