HVAC - Mini-splits - Gree Multi42HP230V1C0 Troubleshooting

[rpaoness]

Woke up to an H5 error code this morning (and some E6's, that may or may not be related). Indication is that the power board that manages 3-phase for the compressor is detecting errors. The service manual has no troubleshooting for H5, but youtube Gree seems to say to use this:
https://youtu.be/h1xkLsoe_Ag

I guess that means I need to check winding series resistance and insulation to ground on the compressor terminals, and do the board diode tests and power supply checks recommended.

Service manual:
https://www.greecomfort.com/assets/our- ... -42k-c.pdf

Parts catalog:
https://www.greecomfort.com/assets/our- ... alog-c.pdf

First error code on this 42k btu unit in 8 years, so not too bad I guess. Two interior heads have had noisy fan motor bearings (replaced one - bought other but didn't swap yet). I guess service has been OK overall.

[rpaoness]

That was weird. And inconclusive.

- Started up to listen to what it was doing - compressor would attempt a start, but about like 3-5 seconds into starting. Sounded normal otherwise.

- Went through the compressor winding series resistance and resistance to ground checks, all checked out OK - compressor connections are on a 3-wire plug.

- Went through board checks for U, V, W terminals and diode checks from P and N to U, V, W. All checked out. "Diode" check voltage readings were about 0.450V and very even.

- Plugged everything back in and checked "live" DC-link voltage - about 340VDC

So everything electrically checked out OK, so I think the objective conclusions would be either:
1.) the board is measuring current incorrectly and believing the compressor is overloaded/failing when it isn't
or
2.) the compressor really is drawing excessive current due to some bearing or compressor mechanical failure

- Attempted a restart and had the compressor run longer, but only about 2-3 minutes.

- Attempted another restart, and ran so-far indefinitely (about 15 min so far), loaded with 4-inside unit 9k btu heads. Seems to be OK now. I wonder how long that will last.

[rpaoness]

Had an E6 code this morning. Rebooting again. I wonder how I figure out if it's a control board vs. actual high compressor current for expected conditions. Control board is $300 if I have one shipped from China. Should dig more to see what else is available.

https://www.aliexpress.us/item/22558002 ... pt=glo2usa

*update* This link is the wrong PN. Looking for 30228000025

[rpaoness]

Rebooted, got E6 on all indoor units. Trying 2nd reboot now.

[rpaoness]

I can’t seem to find one of exactly my PN on the internet. Emailed Ingrams Water and Air - we’ll see what they say.

[rpaoness]

Here's one for $400:

https://www.kingersons.com/GREE-3022800 ... 44601.html

[rpaoness]

Tried many reboots and several iterations of single and multiple indoor head connections. All indications are that it is "random" not following any specific indoor head or head combinations. All signs point to outdoor main board failure.

[rpaoness]

Called these guys since they had an un-priced listing for the board. The first call they hung up on my because I said I was a person and not a contractor. Called back and got a different sales guy and said I was Dura Construction with an underground plumbing license. He said as long as I could email a copy of the license they would have no problem selling to me. Then I asked if they'd ship to Berlin or Old Lyme, and they said that was outside of their Carrier part distribution agreement, so I should go on the Carrier website and find the local Carrier parts distributor. Initial Carrier browsing just points to contractors, not parts distributors. Great. The guy did tell me that it's $662 listed if I could get one through them.

https://www.dcne.com/ContactUs

[rpaoness]

First call w/ Ingrams Water and Air went awful. The kid had no idea what part I was looking for and couldn't tell if the "two boards they had in their system" had anything to do with my 42k unit.

Later I got a voicemail saying to call back if I needed help still. And a return email now looking for model (which I included in my message) and SN, which I didn't include. Sheesh.

[rpaoness]

After calling a whole bunch of places, it appears Baker Distributing has some of these boards in stock in at least Florida and Indiana locations. According to the contractor-account guy I had on the phone, pricing is likely to be $175-$350 depending on how their system prices me up if/once I have a contractor account.

I filled out all of the account paperwork as Dura Construction, including tax ID and contractor lic number. They did ask for a contractor HVAC cert (EPA 608 I assume - it just said EPA cert). I posted a *.pdf that said no refrigerant purchase expected/permitted to satisfy the online system that a file was there. I don't know if that will work. I just bought an EPA 608 universal study guide off Amazon and I'm planning on scheduling and taking an online test with ESCO at some point in the near future. Should be about $105 total - $20 for the study guide and $85 for the exam to get certified.

Baker Dist Part listing:
https://www.bakerdist.com/gree-30228000 ... d--f697b09

Test website:
https://www.escotesting.com/remote/default.aspx

Study guide:
https://www.amazon.com/gp/product/B0CM8 ... UTF8&psc=1