FoxESS Community - Owners & Installers Forum

Hi all. I'm a relatively new owner of a Fox ESS EP5 battery and Fox Hybrid/AC Inverter. We've just switched to an octopus flux tariff so have started using the force charge settings on the foxcloud app.

Yesterday evening the app started showing Error Code 222 (BMS Charge Require No Reply). Searching this forum showed advice to turn the battery off and on again while leaving the inverter on; I did this but the error persisted and was joined by Error Code 194 (Battery Over Voltage).

If useful context temperatures have been sub zero for the last two days and both battery and inverter are outside.

Fast forward to this morning. Error Code 194 has disappeared but 222 persists. I tried turning it off and on again - I read that if the inverter shows the SOC percentage then communications have been restored. The inverter is indeed showing the SOC on its display panel, but the app still shows the fault and the battery will not force charge from the grid - so I still seem to have the error.

I've emailed Fox customer services but have no idea how quickly to expect a response so thought I'd see if anyone here has any advice.

Thanks very much in advance!

Sounds like the battery is too cold to accept a charge. What temp is shown in the v2 fox app under devices > battery?
Anything low single digits and your battery will shutdown and refuse to work until it's warmer.

Thanks so much for the quick reply. It's currently showing -0.2 degrees. For what it's worth the outside temp has been very cold especially over night for some days now but I guess the battery will have held some heat for some time and gradually reduced?

Either way - would the temp being too low to accept a charge cause the error to display do you think?

Those errors are exactly that, your battery is too cold and is refusing to charge and your battery is below the required operating temps so is just sat waiting for the temp to increase.

Visit your local DIY store and buy a board of insulation board and some strong tape and build a box that you can slide over just the battery. The inverter is happy at very low temps, it's just the battery that needs insulating during the coldest part of the year.

Very interesting, thank you. So presumably when the battery gets over 0 the error should go and the battery charge?

I'll definitely look into making a box too, thank you.

You'll likely not see much battery activity until it gets over 5c with around 10amps of battery charge/discharge possible at around 10c.
Might be worth a watch of this video I made a few winters ago.

Brilliant, thanks again for your help, I really appreciate it.