Tell us the battery's charge level, the work mode, any Mode Scheduler block and the name or code of any alarm the Fox Cloud app shows. We cover all Fox ESS models, and with your permission we work through your login or an account transfer.
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I contacted Solar Tech Support with an issuewith my solar and Ron went out of his way to help me. Despite the fact that I'm situated hundreds of miles away and he knew there'd be no business opportunity from my inquiry, Ron still chased solutions and helped me get an understanding of what I needed to do. I love working with people like this, people with integrity and service at the heart of what they do. I just wish hew was nearer!
Amazing support, went out of his way to help try and get us back up and running
Our SolarEdge PV system with LG batteries had its first hiccup after 8 years of hard work. The Inverter failed. Fortunately I found Solar-Tech-Support who diagnosed the problem very quickly, ordered a replacement unit and fitted it shortly after we received the unit from SolarEdge. Very thorough and professional approach. Thank you, a solid 5 star recommendation.
My old solax packed in and was replaced by solar tech support. I am impressed at the very short time scale, sorted in only 3 days. Some were quoting 2-3 weeks. The old unit and all the packing was taken away.
Ron was extremely helpful and tried his best to repair/reset our GivEnergy inverter remotely. In the event he was unsuccessful but he couldn’t have been more helpful. If you have problems with a GivEnergy system please contact him. Highly recommended
We have a GivEnergy system, both GivEnergy and our installer have gone bust! Ron was able to remotely log in to our system and sort the issue within about 30mins. Would definitely recommend and will be using in future
Open the FoxCloud 2.0 app, not the web portal, which a moderator on Fox's Tech Hub forum said in July 2025 doesn't show the battery. Note the battery's charge level, if it's charging or discharging, the work mode, any Mode Scheduler block and the name or code of any alarm under the bell icon. The settings in steps 2 and 3 are ones Fox says owners can change themselves. The app's menus can vary by model, firmware and account type.
The charge level stays low or stops rising, from solar or from the grid. Start at step 1 below.
The house runs from the grid while the battery holds its charge, or the app shows standby. See a battery that won't discharge.
Work through these in order. Steps 1 to 5 are checks in the app. Step 6 is one restart of the whole system, only if an alarm is still showing.
Use the FoxCloud 2.0 app, because a moderator on Fox's Tech Hub forum said in July 2025 that the web portal doesn't show the battery. The app's battery screen shows the battery charging or discharging, its power and its temperature. Alarms sit under the bell icon at the top right, in Current and History lists. Older versions of Fox's app manual call the screen Faults, under Me. A battery communication (BMS) alarm or an over-temperature alarm stops charging until it clears. Note the alarm's name or code exactly as the app shows it, and look it up in our Fox ESS fault code index.
The work mode is on the inverter's page in the app, and Fox says owners can change it themselves. In Self-Use, solar supplies the house first, then charges the battery, and only then is anything exported. With no solar, the battery covers the house. In Feed-in Priority, solar supplies the house first and is then exported, and the battery charges only from what's left over, for example when the export limit is reached. If the house is using all the solar, there's nothing spare to charge with in either mode. If you want the battery to store your spare solar, choose Self-Use, then check the battery screen the next time the panels are making more than the house is using. Back up mode keeps charge in reserve for power cuts, so if your battery is charged but not being used, see the section below on a battery that won't discharge.
Since the FoxCloud 2.0 app's V2.2.0 update in February 2026, Fox has removed the old grid-charge settings. Timed charging and discharging are now set under Work Mode, then Mode Scheduler, then Add a Schedule. "Force time use" is the name in Fox's inverter manual, which still uses it in its October 2026 issue; the app has no mode of that name. A Forced Charge block has a start and end time, a charging cut-off SOC and a Charge from Grid switch. With the switch on, the battery charges from the grid during the block. The block also sets what happens once the battery reaches its cut-off, for example going back to Self-Use. Outside your blocks, the system runs its "remaining time" mode, which is Self-Use unless you change it. Wrong times in a block, a low cut-off SOC or a low System Max SOC limit all stop charging early. If Mode Scheduler isn't in your app at all, Fox says the inverter's firmware needs upgrading. Ask Fox ESS's service team or your installer, because some older models need a manual upgrade. Fox's January 2026 firmware for the H1-G2 also fixed schedules that didn't charge in some periods, and it lets a schedule run across midnight. The reserve settings stop the battery discharging, not charging, and they're covered in the section below.
Check the app's alarm history for a BMS communication alarm. It means the inverter has lost its data link to the battery's management system, and the battery won't charge or discharge until it clears. Fox's H1-G2 manual names these alarms BMS Lost, Bms Ext Fault and Bms Int Fault, and Fox Cloud shows BMS Lost as code 14. Other battery alarms have their own names, such as Bms Temp Low (battery under-temperature), Bms Volt Low (battery under-voltage) and Bms Ver Unmatch or Bms M&S Unmatch (mismatched battery software: Fox advises a firmware update after adding batteries). For these, Fox's H1-G2 manual says to contact the battery supplier (its KH manual says Fox's service department). Bat Power Low means the battery's charge is low, and Fox says to wait for it to recharge, or to contact Fox ESS if it doesn't. Fox writes the checks for these alarms, such as the communication cable, for installers. So give your installer, or us, the alarm's exact name or code rather than checking cables yourself. On a stack of ECS modules, Fox's manual shows module faults on the battery's own lights. If an alarm keeps coming back, it may be a cable or battery fault, and Fox's route is your installer or the battery supplier. Our Fox ESS BMS communication fault page has more on each alarm.
Fox's ECS documents list no heater, so an ECS charges only from 0 °C upwards. Fox ESS UK says the EQ4800 has no warm-up, and that warming is off when EQ modules are mixed with an older ECS. The EP range is the main one in the UK with a heater. Fox's Tech Hub says batteries without internal heating charge only between 0 and 55 °C and discharge between -10 and 55 °C, and go dormant slightly outside that range until they're back within it, but that isn't a rule for every Fox battery: the EVO 10 manual says its batteries charge above -20 °C or -10 °C, depending on the cell type, even with heating off. When the battery's coldest cell is below 3 °C, its management system uses a little solar or grid power to hold its charge, which also helps warm it. Fox's ECS4800 datasheet (V2.0) also slows charging between 0 and 15 °C. Batteries that can warm their own cells include the EP6, the heated EP5 and EP11 (Fox calls them EP5-H and EP11-H) and EQ "(w)" models. Warm-up runs only when it's switched on and every battery in the stack has it, and Fox staff say first-generation inverters can't use it. To tell whether an EP battery has heating, Fox says to look for warm-up options in the Fox Cloud app, or at the serial number: 60EP0 is standard and 60EP1 is heated. If you're not sure, check the warm-up settings in the app, or ask your installer. Cold-weather protection clears as the battery warms. If the app shows Bms Temp Low (battery under-temperature), Fox's action is to contact the battery supplier.
If an alarm is still showing and you want to try a restart, restart the whole system once, not one device. Our order for a Fox ESS system is the battery's power button first, then the AC isolator, then the inverter's DC isolator, and the battery's DC MCB last if it has one, so the MCB is never switched under load. To turn it back on, go in reverse: battery DC MCB, DC isolator, AC isolator, then the battery's power button. Read the full shutdown guide. Check the Fox Cloud app to see whether the alarm has cleared. Fox's action for BMS Lost is the cable check in step 4, not a restart, so if the alarm comes back, stop there. If the battery still won't charge, contact STS for a remote diagnostic.
If the battery has charge but the house is running from the grid, check these in the Fox Cloud app.
The battery stops discharging when it reaches its on-grid reserve. Fox's February 2026 app manual (V2.1) calls this level System Min SOC, and calls the level for power cuts Backup Cut-off SOC. Fox's July 2025 manual called the on-grid level Battery Reserve Capacity, and the inverter's own menu calls it OnGrid Min SoC. Fox says owners can change these settings, though the options shown vary by account type, region and device. If a change to these levels won't save and the app says "write failed", a moderator on Fox's Tech Hub forum advised (February 2026) switching Mode Scheduler off while you make the change. Fox's January 2026 firmware notes for the H1-G2 say the battery goes idle once it reaches that on-grid minimum.
During a Forced Charge block, the battery is charged first rather than supplying the house, while a discharge block lets the battery supply it. A moderator on Fox's Tech Hub forum says a Force Discharge block's SOC takes priority over the on-grid reserve until the block ends. If a Force Discharge block reaches its cut-off SOC before it ends, the battery can stop supplying the house for the rest of the block. Fox staff described the battery idling at its discharge limit in June 2025. A forum moderator said in March 2026 that changing this was planned, with no date confirmed, and in July 2026 that an update lets a block act on its cut-off SOC or its time window.
Fox describes Back up as keeping charge in reserve for power cuts. Owners report that it holds the battery at its set level rather than running it down for the house. For backup in a power cut, see our Fox ESS EPS not working page. Feed-in Priority puts the battery last in line for solar, but an answer on Fox's Tech Hub forum says the battery still supplies the house.
Fox's non-heated ECS, EQ and EP batteries go into Power Reserve Mode when the battery's coldest cell is below 3 °C and its charge is under 60%. They won't discharge until they have charged back to 65% or the coldest cell warms to 5 °C, and below -10 °C they don't discharge at all. Fox calls this a protection that clears as the temperature rises. A BMS alarm or a battery protection event stops discharging as well as charging, and it shows as its own alarm in the app.
Standby has its own pattern on an ECS battery's control module. Fox's manual shows standby as a flashing green light with the red light off and the charge-level lights steady. When the battery is discharging the green light is steady, and when it's charging the charge-level lights flash. The EP5 has its own light table in its manual, which is on our Fox ESS documents page.
During Fox's cloud outage on 11 March 2026, the app showed some batteries as offline or in standby. A moderator on Fox's Tech Hub forum said the app had been investigated and systems had returned to normal, so a standby or offline label in the app isn't always a battery fault. If the whole system shows offline, see our Fox Cloud offline page.
If the battery's own lights show a fault, or it stays idle with charge left and none of the above applies, that's for your installer or the battery supplier. Owners on the independent FoxESS Community forum, which Fox ESS doesn't run, describe idle batteries that turned out to have a module fault, or a protection lock that Fox ESS had to clear.
Fox's documents set out how each work mode shares solar between the house, the battery and the grid. Self-Use charges the battery before exporting, Feed-in Priority exports before charging it, and Back up keeps charge in reserve for power cuts. Since February 2026, forced charging and the other timed settings have been in the app's Mode Scheduler, and the reserve settings are in Quick Settings. Fox says owners can change the work mode, Mode Scheduler, schedules and the SOC settings themselves, while grid protection and export limits are for installers.
A BMS communication alarm stops the battery charging until it clears, and Fox's action for it is a cable check, which is for your installer or an engineer. We cover all Fox ESS models. With your permission we look at your Fox Cloud data, alarm history and settings, through your own login or after an account transfer (£95). We're independent: not affiliated with or endorsed by Fox ESS.
Tell us the battery's charge level, the work mode, any Mode Scheduler block and the name or code of any alarm the Fox Cloud app shows. We cover all Fox ESS models, and with your permission we work through your login or an account transfer. Independent: not affiliated with or endorsed by Fox ESS.
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