One string stops working, support says everything works fine

[dnatand]

I have a 8.8kW system (4 strings) and a Powerwall+. Recently, the total generation is significantly lower than at the same time last year. I checked the Powerwall dashboard and noticed that 1 string has stopped producing power. I contacted Tesla's online support, but they told me that 1) customers are not supposed to use the gateway to check solar details (may void warranty) and 2) my system is working fine based on the energy generated.

How can I get this issue fixed? It takes forever to get connected to phone support.

 

[jjrandorin]

There is no advice that can be provided here to "how do I get this fixed" other than "keep calling / keep asking". We do not have any "In" with Tesla energy, and this website is not affiliated with Tesla.

The one piece of advice I would give you is CALL (not online support, not email, not chat). Keep CALLing. Get a ticket number when you call, and call again and reference it a few days later. Dont use anything that can be easily ignored, and EVERY means of online communication can be ignored without even responding to someone.

Other than that, there is no other advice we can offer you to getting customer support on your system from Tesla.

 

[dnatand]

Thanks for the response. I wasn't expecting any help from an insider, just to get some advice from the community. I finally spoke to a phone agent who claimed to be a "tier 1" agent. However, they couldn't seem to access more information than the "tier 2" online chat agents. Again, they claimed everything appeared to be in order. The only option they offered was to schedule a maintenance visit, but if the inspection found nothing wrong, I would be responsible for the $300 visit fee...what a joke.

 

[offandonagain]

A few things to check before you commit to that service visit fee:

1. Are you positive string D is connected? You can't rely on design plans really, since the actual install can differ from the design. If you have historical data from Powerwall Dashboard showing production on all 4 strings, that's good evidence. If you're comfortable with the process, you could also lift the inverter door and look at how many strings are connected to MPPT ports.
   
   
2. When you say generation is significantly lower than last year, how big is that difference? Best to check on a sunny day around solar noon. If you post screenshots of solar generation last year and now (both from a clear day), we can help compare.

Once you're confident that the string is having issues, the service visit makes sense. They should be able to quickly verify that using the Tesla Pros app.

 

[dnatand]

Good tips.

1. All 4 strings were producing after installation last year. Unfortunately I lost historical data from Powerwall dashboard after recent reinstallation but I'm positive all 4 were working.
2. The diff is 4.7kW vs 7.2kW compared to last year around same date/weather (NorCal sunny days). So I guess that's quite evident.

The only thing I'm not sure if how long has the string been having problems and if it can recover by itself. I'll wait a couple of days before scheduling the visit.

 

[offandonagain]

Ok, this does look like an issue with your string then. Assuming you have 400W panels, your system has 22 total. String A and B look to be ~4 panels each, String C is ~8 panels. So the faulty string has 6 panels. Depending on orientation, that's a ~27% loss (more if this string is south-facing and others are not).

You might be able to tell from monthly charts when the problem started. You could try power-cycling your system in case it's a string fault that can be cleared. If that doesn't help, schedule the service.

 

[patrick40363]

I have a 8.8kW system (4 strings) and a Powerwall+. Recently, the total generation is significantly lower than at the same time last year. I checked the Powerwall dashboard and noticed that 1 string has stopped producing power. I contacted Tesla's online support, but they told me that 1) customers are not supposed to use the gateway to check solar details (may void warranty) and 2) my system is working fine based on the energy generated.

How can I get this issue fixed? It takes forever to get connected to phone support.

View attachment 1030465

Try turning the inverter breaker off for a minute and then back on. You might see the production go back up. I have a problem with mine and that seems to help. Tesla came out and can't figure out what is causing my problem. Of course they say it is producing within the numbers they have.

 

[jgleigh]

Check the alerts for String D. You could have an open MCI.

 

[dnatand]

Now this is beyond my comfortable zone of troubleshooting. How exactly can I turn the inverter breaker off and back on? Any sequence of operation I need to follow, e.g. turn off the battery first..

The only alert I see is from the Powerwall dashboard but I don't really know how to interpret.

 

[jgleigh]

Not sure that tells us anything else. They're going to have to come look at String D. It's either disconnected, there's an MCI issue, or there's an issue with that MPPT connection at the inverter.

 

[patrick40363]

Now this is beyond my comfortable zone of troubleshooting. How exactly can I turn the inverter breaker off and back on? Any sequence of operation I need to follow, e.g. turn off the battery first..

The only alert I see is from the Powerwall dashboard but I don't really know how to interpret.

View attachment 1030640

I have a breaker box with a breaker for my 3.8 and 7.6. I just turn off the inverter I am having problems with. I don't touch my 2 powerwalls or gateway.