FoxESS Community - Owners & Installers Forum

I am a newbie with a month old instal that has worked OK until this week of freezing weather. It is on my separate garage building and the inverter and battery is similarly unheated. For the last day or so, the SoC has dropped from 37% to now 6% !! despite the min SoC being set first at 30% and then reset to 15% when it failed to react to being below 30%. I have tried several forced charging periods with no effect (no visible sign of inverter trying to put charge into battery).

Any ideas of what to check or try ?

I have a 5kW H1 inverter with about 4.8kWp of panels and 2x HV2600 batteries

Many thanks, Asyrop

Yep, too cold at the min, the BMS will throttle the charge rate but it won’t charge at all at 0deg or lower. You need to warm the battery up

Thanks for replying - I would not mind so much it reducing the charge rate but stopping altogether and also letting the battery run down to 1% with no errors seems quite unreasonable. Given there is nothing in the manual to say the units stop working when freezing or advising mounting them in a warmer space, it is a serious failure for any UK install, in my view.

The manual makes no mention in the main text of these issues. It does state the Battery operating range is -10°C to +50°C although ominously in the System Spec that the operating range for charging is 0°C to +50°C, whilst discharging is -10°C to +50°C - what use might there be in the ability to draw energy at low temperatures but not be able to replace it without warming the battery ???

I've checked the database log of temperatures but they are all above 0°C unless they are clarly empty datapoints stuck at 0. Anyone by chance know what is operative in this respect ?

I have called my installer who is waiting on Fox - he does not want me to warm the batteries but turn them off even at 1% SoC. If they suffer as a result of being so heavily discharged, then it will be his problem.

Anybody know more or are we at the edge of what the manufacturer is prepared to share ? Thanks in advance

When I say warm the battery up I mean it needs to be in a warmer environment to get the most out of it, these limitations are definitely a pain for a UK winter and I wasn’t told about them either. My solution will be to make an insulated cover to go over them in the cold months, hopefully I’ll have time over the next week to do this and will post my results

I too had the same problem.. I happened to have an old electric blanket so wrapped it around 3 sides of the inverter and then covered it with 3 old duvets ! 36 hours later it was working again .
I too plan some form of waterproof insulation if we have another cold spell.
I am disappointed my installer didn’t explain this when locating it on an outside wall.
He also failed to set up the EPS and now thinks he has lost the connector plug ! Any ideas where I can get one appreciated.

Contact the installer, failing that, get n to Fox direct.
Re. The EPS, it’s actually very good, but you need to fit a changeover relay to be able to use the main supply under normal operating conditions, as the EPS output is somewhat current limited.