Battery failure (red status light)

I have two gen 2 3.5 hybrid inverters, each with two 8.2Kwh batteries. I know this is "not supported" but it's what my installer sold me. I'm waiting for the EMS box, as are others, when all my problems will disappear overnight – I wish...

However, after working well for a couple of months, one battery developed a red status light and wouldn't charge. It's now been disconnected, after both the installer and GivEnergy were unable to get it working again. My installer is saying it's the fault of the plant system and they won't do anything until EMS is installed.

However, I doubt that's the case (one of their engineers contradicted the office manager, saying it it is most likely a faulty battery). Can anybody suggest why a battery would not charge on a plant system? Is the installer simply pulling the wool over my eyes?

I want my full system back again but I don't have the technical clout make the argument myself.

Much appreciated...

SurreyMuso Installer is responsible for repair/replacement if something fails in the first 6 months. If they chose to install a configuration which the manufacturer doesn't support then that's their problem - and liability.

Time to remind them what their legal responsibility is.

I don't suppose by any chance you paid part of the cost (over £100) via credit card? If so then get the card issuer involved as they are jointly and severally liable. The card issuer will seek to recover costs from the installer, including putting the installers into administration if necessary, which will carry more weight than you threatening legal action.

Vestas I paid the first £100 of my ASHP and then solar system on a credit card for jus5 this reason.

If the installer designed and install a plant system then agree, it’s their responsibility to resolve issues with it.

SurreyMuso My installer is saying it's the fault of the plant system

I don't believe that multiple inverter systems are "not supported", but they are "not recommended" by Givenergy. There are at least three of us on here with two hybrid inverter/batteries. The only issue with having multiple hybrid inverters is that the portal doesn't quite add up correctly. There was a report of an issue with cross charging on later hybrids, but not gen1 (which we have and @geoffreycoan).

Anyway, speak to Givenergy. A faulty battery has nothing to do with there being multiple inverters. The inverters don't even know of the existence of each other, as long as your installer hasn't connected them together over Modbus. Even if he has connected them together over Modbus, if the battery has a red light, it's the battery that's faulty and is under warranty.

Tim absolutely agree with you, it’s nothing to do with the plant system, the inverters don’t know anything about each other, that’s FUD from the installer.

BTW Tim I have in the last week started experiencing a cross charging issue. It’s caused by me having different sized batteries so they discharge at different rates and when predbat sets the minimum soc overnight in the flux off peak period to hold the battery charge for the next day, the fuller battery ends up cross charging into the less full battery. Am working through the issue with Trefor Southwell, trying the new “balance inverter” option in predbat.
This is a very specific edge case with multiple inverters and automation, in normal use as above, the gen 1’s work perfectly together apart from the screwy portal data

Tim Thanks, Tim. Much appreciated. I have Gen 2 inverters and can confirm they are definitely cross charging. Graphs show one is discharging at the same time and approx the same rate (minus overhead) as the other is charging. Same every night.

Awaiting the EMS box, though I am investigating Home Assistant on a RPi to stop the cross charging.