FoxESS Community - Owners & Installers Forum

Hello All,

Finally got the battery warming F/W updated so it was actually working, however now, the period that it's allowed to pull from the grid is seemingly being ignored.

I have a 3AM to 5:30AM slot and a 12AM to 13:30PM slot to allow from grid. However from about 9AM to 12PM it's decided to pull from the grid when my Heat Pump was working and cost me a bunch.

This is the first setting showing my settings for when it can use the grid. Here is the second screenshot showing that at around 10AM the system starts pulling from the grid.
At this time the battery temp did drop below 9C to allow the heating to kick in from the battery (which was above 40%). What is going on here?
Battery is set to self use during this time, is it just that the pack got too cold to even power the house? In which case should the battery warm up feature not be coming on sooner that 9C?

Only now after toggling the feature on and off a few times has it decided it's happy to pull from the battery again. Even though I got the 'sucess' messages while setting this function up initially.

Temp of the battery is still down at 6.7C.

If you read the posts in this thread from @albie999 you can see he has done some testing of the heater and bugs.
viewtopic.php?p=10761#p10761

MaterialBarracuda48 wrote: ↑Tue Jan 06, 2026 12:44 pm If you read the posts in this thread from @albie999 you can see he has done some testing of the heater and bugs.
viewtopic.php?p=10761#p10761

Ah perfect! So does not seem like my user error then seeing a few of those replies. I will read throug the rest of the post.
Seems like you need to manually turn the feature of and on for when you want it?

greensolarostrich wrote: ↑Tue Jan 06, 2026 12:50 pm Ah perfect! So does not seem like my user error then seeing a few of those replies. I will read throug the rest of the post.
Seems like you need to manually turn the feature of and on for when you want it?

I have mine set to heat from grid during IOG cheap rate of 23:30 to 05:30. Temp min is 9C max 15C for on/off.
Then after this period it was heating from excess solar... but never from it's own SoC, even when above 90%.

Running v1.009, with hopes that in next few hours they upgrade this to v1.011 or whatever is current.

I have also experienced blocked discharge when cold, I think it was 7C, but was trying to heat from solar panels covered in snow yesterday. I had to turn off heater to allow it to feed house, once snow was cleared off panels, I could turn on the heater and it warmed up from PV (I think it likes above 1kW?)

Anyhow, Albie999 has done some good testing of things there, so a useful read
Glad you have heating now!

Looking forward to your 1.011 testing ..... I chased Fox again this morning .... as had not had a response, and I was advised "ive escalated to RND about the problem , will get back to you asap"

So lets see what happens. But like you, and other people .. am having to manually turn on/off the heater to stop grid pull ... obviously .. I cannot monitor it 24/7 ... so definitely costing me money

albie999 wrote: ↑Tue Jan 06, 2026 3:34 pm Looking forward to your 1.011 testing ..... I chased Fox again this morning .... as had not had a response, and I was advised "ive escalated to RND about the problem , will get back to you asap"

So lets see what happens. But like you, and other people .. am having to manually turn on/off the heater to stop grid pull ... obviously .. I cannot monitor it 24/7 ... so definitely costing me money

Speak of the Devil.

I have only had the Inverter upgraded this morning. No idea why they skipped battery. No email in spam/inbox to say they even did anything.

Anyway, glad that you have been posting good information in the battery heater thread, useful information to help all.
As always, when the temperature drops, the messages appear.

Hi new to the world of batteries and warm up etc. Anyway, had an update and now the warm up function is available. However would appreciate the optimal settings ie trigger temps and also how to make the battery use its own energy to warm as using expensive energy to release cheap energy seems illogical unless it can damage the battery. Appreciate any thoughts as I drain the batteries every day and have 4xEP12 and an H1 6kw inverter.

Keep seeing the battery take power from the grid at peak times and also then deliver power back to the grid which I had not planned on or expected. Appreciate any guidance J

jonathanb48 wrote: ↑Tue Jan 06, 2026 5:04 pm Hi new to the world of batteries and warm up etc. Anyway, had an update and now the warm up function is available. However would appreciate the optimal settings ie trigger temps and also how to make the battery use its own energy to warm as using expensive energy to release cheap energy seems illogical unless it can damage the battery. Appreciate any thoughts as I drain the batteries every day and have 4xEP12 and an H1 6kw inverter.

Keep seeing the battery take power from the grid at peak times and also then deliver power back to the grid which I had not planned on or expected. Appreciate any guidance J

Current Temperature?
Batteries are Outside/Garage/Inside?
Can you find your battery FW? (Fox Cloud 2.0 App, click on battery icon and then serial number for a battery)

BMS v1.009 for me, Start (min heat) is 9C, End (max heat) is 15C... you can move up/down for example 7C/13C as Start/End points.

Now regarding the BMS FW, sadly v1.009 can heat from Grid warmup, or from PV (I think above 1kW being generated) it is NOT for me using self-power to heat what so ever. I have had 90% to 100% SoC since this morning and it never heated from internal power.

I am trying to get v1.011 pushed to it.

Hi yes the batteries are outside and we’re down to -2.5c but are now between 7 and 15c - I have set the warm up at 7 and 13c. Software is master 1.47!and 1.35 manager. Very strange was that the charge cycle suddenly dropped for 30 minutes at about midnight last night and simply didn’t charge - very weird

And BMS is 1.011

jonathanb48 wrote: ↑Tue Jan 06, 2026 7:16 pm Hi yes the batteries are outside and we’re down to -2.5c but are now between 7 and 15c - I have set the warm up at 7 and 13c. Software is master 1.47!and 1.35 manager. Very strange was that the charge cycle suddenly dropped for 30 minutes at about midnight last night and simply didn’t charge - very weird

I know on my current v1.009, it heats at 23:30, and some point around midnight give or take (though I think it's above 9C there abouts) it begins to charge, and carries on heating at same time for me.

jonathanb48 wrote: ↑Tue Jan 06, 2026 7:17 pm And BMS is 1.011

I am totally NOT jealous!
Pleased for you, hope it carries on behaving well.

I guess I don’t know what behaving well is yet but I do know I have become very boringly interested in the power load of my house!!

jonathanb48 wrote: ↑Tue Jan 06, 2026 7:27 pm I guess I don’t know what behaving well is yet but I do know I have become very boringly interested in the power load of my house!!

Yes, once you get into it, you start to get angry at the sky when clouds roll in. I still joke sometimes when sunlight pours in "ooh look, money!"

Anyhow I have gone off topic, enjoy your system.

I am having a similar problem that I hope someone can assist me with.

I have EP6 batteries and an H1 v2 3.6 kw inverter, in an enclosed garage with battery temperatures currently around 7 degrees. I was recently upgraded to BMS 1.011 which has enabled the battery warming function, however whenever I activate it and battery temperatures are within range, it immediately reboots the inverter and my house supply reverts to the grid. The function seems to provide no warming effect at all. The inverter continues to cycle through its checking procedure until I switch off the battery warming function whereupon things slowly return to normal. The installer is looking into it but… any thoughts please?

Pagglukia wrote: ↑Fri Jan 09, 2026 3:02 pm I am having a similar problem that I hope someone can assist me with.

I have EP6 batteries and an H1 v2 3.6 kw inverter, in an enclosed garage with battery temperatures currently around 7 degrees. I was recently upgraded to BMS 0.011 which has enabled the battery warming function, however whenever I activate it and battery temperatures are within range, it immediately reboots the inverter and my house supply reverts to the grid. The function seems to provide no warming effect at all. The inverter continues to cycle through its checking procedure until I switch off the battery warming function whereupon things slowly return to normal. The installer is looking into it but… any thoughts please?

BMS is 1.011 (typo above)

Take a look at this thread here...
viewtopic.php?p=12074#p12074

Go down 2 posts to see Dave Foster's comment about how to check/change value

Thanks for this, I have edited my firmware error and will pass on this useful info to my installer

Pagglukia wrote: ↑Fri Jan 09, 2026 4:31 pm Thanks for this, I have edited my firmware error and will pass on this useful info to my installer

You should be able to follow Dave's advice in the linked thread, and self check these values yourself on your inverter screen, default password is usually 0 0 0 0 if it asks.

Update - Our excellent installer has tweaked the settings based on this advice, and the problem seems to be fixed. Now the battery warming function appears to work correctly without crashing the inverter. Thanks Fox Community for your expertise!

Pagglukia wrote: ↑Fri Jan 09, 2026 6:33 pm Update - Our excellent installer has tweaked the settings based on this advice, and the problem seems to be fixed. Now the battery warming function appears to work correctly without crashing the inverter. Thanks Fox Community for your expertise!

Thank you for popping back.
Credit to Sunny65 for posting up the fix and Dave for confirming there have been a few reports about this.