Tell us what you're seeing — fault code, what Solarman shows, what changed recently, what the battery is doing. We'll identify the fault and give you the fastest path to a fix.
Book your free remote diagnosticSolar not working at all?Independent — not affiliated with Sunsynk Energy.
Ron has come to our rescue once again! After sorting out our GivEnergy battery issue, he was on hand to help us find a solution to data logging issues caused during install of an additional inverter. He's helpful, patient and extremely knowledgeable. Utterly brilliant service. Thank you again!
Had a fault on a GivEnergy AC coupled 3kW home battery and was getting no joy from multiple companies I contacted, as well as the original installer. Contacted Solar Tech Support and they sorted it really quickly, now working perfectly again, can’t recommend them highly enough, professional and very responsive!
My installer put me through Hell with so botched install that you can not imagine Than Ron came , He did not managed to do miracles (because my system components were impossible to work together) and he Gave me a detailed report of what is wrong , why is wrong , why can not be fixed etc. with all the details which I can use in a claim. Without His his help knowledge and attitude I would've been lost
I left an enquiry few days ago and got a call back today from Ron. I have FoxESS battery and inverter that seemed not doing the right job and after only few questions, Ron told me exactly what I need to do to restart my system, without even seeing it. After almost 2 weeks of not being able to use my FoxESS equipment, today is finally up and running. Very professional and knowledgeable. Thanks Ron
Called spoke to Ron. Was very informative and more importantly listen to the issues regarding my system. Was very professional and tackled the problem and had my system back on it's way. Thank you once again Ron
Brilliant service from Ron - our GivEnergy inverter stopped working on Tuesday what a nightmare seen as the company who installed it are no longer in business. Through social media I found STS (Ron) he had a new inverter and it was fitted and working by Friday - what I thought was going to be a nightmare turned out not to be!!! Great guy great company - def my go to now for anything solar related - Thank you so much
The most common Sunsynk call-outs. Nearly always a configuration issue — TOU schedule, grid charge enable setting, or SoC threshold — that can be resolved without a site visit.
No green or red LED on the logger and nothing in the app, while the inverter itself runs normally. Usually the 12V supply on the board behind it rather than the logger, the fault Sunsynk trace to capacitor C9. Free checks first.
See Sunsynk-specific guide →Charge window set correctly in Solarman but battery stays at minimum SoC. Covers TOU schedule errors, grid charge enable being off, SoC minimum threshold, and Octopus tariff clock offset issues.
See Sunsynk-specific guide →Sunsynk integrates with Octopus Agile, Intelligent, and Go but the TOU schedule must be precisely configured. Common issues: charge windows offset by BST/GMT, grid charge enable toggle, SoC target not high enough.
See Sunsynk-specific guide →Battery shows charged but the house draws from the grid at peak times. Usually a discharge schedule configuration error, SoC minimum set too high, or an EPS battery reserve threshold preventing normal discharge.
See diagnostic guide →Low or zero solar generation, unexpected grid imports, and EPS backup not activating during a power cut. Check Solarman for DC input voltage and error codes first.
Sunsynk hybrid inverter powered but showing zero or low generation. Check Solarman for DC input voltage readings. Common causes: DC isolator tripped, string fault, grid overvoltage curtailment, or export limit active.
See diagnostic guide →House lost power during a grid outage despite a charged Sunsynk battery. EPS (Emergency Power Supply) mode must be correctly wired and enabled in settings. Also covers EPS SoC reserve threshold and load circuit configuration.
See diagnostic guide →Solarman going offline is most often a datalogger WiFi issue after a router change or broadband switch.
Solarman (formerly PVMaster) shows no data or last updated hours ago. The system usually keeps running, but offline doesn't prove it, so check the inverter's own screen. Router changes, password updates, and logger hardware failure are the most common causes.
See diagnostic guide →Sunsynk dataloggers require 2.4GHz WiFi. Many monitoring failures after a router upgrade are caused by the new router defaulting to 5GHz or using band steering. If the datalogger won't reconnect, we can set it up on site, from £195.
See diagnostic guide →Sunsynk fault codes appear in the Solarman app and on the inverter display. Common code groups cover grid voltage faults (F43 and F44), battery communication errors, DC bus faults, and temperature protection trips. Share your exact code when you book — we identify the root cause as part of the remote diagnostic.
Every fault guide above is built from real Sunsynk diagnostic sessions. The pattern we see most often is a homeowner who has set up their charge schedule correctly — the windows look right in Solarman — but the battery still isn't charging at the cheap rate. The root cause is almost always one of three things: the grid charge enable toggle, an SoC minimum threshold that's too high, or a BST/GMT offset after the clocks changed. None of these require a site visit.
Sunsynk's Solarman monitoring platform gives us a detailed view of charge/discharge history, TOU schedule logs, DC input voltage, and fault code registers. That's why most Sunsynk problems, including grid disconnection faults, can be fully diagnosed and resolved remotely, often in a single session. The exception is a datalogger that has dropped off your WiFi: we can set it up on site, from £195.
If your fault isn't listed above, or you've worked through a guide and the problem persists, book a remote diagnostic. We're independent from Sunsynk Energy and your installer — you get an objective second opinion on what's actually wrong and what needs doing.
Independent Sunsynk hybrid inverter diagnostics — Octopus tariff configuration, BMS comms, battery charging. Free remote diagnostic — no fix, no fee.
See Sunsynk hubEvery Sunsynk F code explained, including F56 DC_VoltLow_Fault and F14 DC_OverCurr_Fault. What each means, the cause, and whether we can fix it remotely.
See fault codesA remote diagnostic session finds the exact cause using your Solarman data, error history, and TOU schedule — then gives you a clear repair plan. Most Sunsynk problems are resolved in a single session.
Due to unprecedented demand we’re currently only carrying out on-site work in Yorkshire, and replies are taking up to 7 days. Remote diagnostics continue for the whole UK as normal.
Every message is read and answered, so please don’t send it twice; that only slows the queue.
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