How to request a Sunsynk firmware upgrade

There is a technical reason the process is best left to the support team. Sunsynk inverters "generally have two firmware sets to keep updated, one for the LCD/Comms and one for the MCU"³, and a mismatched pairing can cause real symptoms: some firmware updates can resolve issues with CTs not reading properly where the inverter is running incompatible firmware pairings, and refreshing the firmware can start the CT reading properly again⁴.

Why an update is occasionally needed

Firmware on a solar inverter is not like an app on a phone that updates every fortnight. Sunsynk describes updates as occasional, and the reasons are specific: new features, improvements and compatibility updates, which in practice often means making the inverter work correctly with a particular battery or fixing a communications fault¹. The two-set structure matters here. Because the LCD and communications board and the main control unit each run their own firmware, they have to be kept as a compatible pair, and a fault such as a CT clamp that stops reading correctly can be a symptom of the pair being out of step rather than a hardware failure³.

For a household aiming at energy independence, this is one of the quiet dependencies of a hybrid system: the inverter's behaviour depends on code the manufacturer can change remotely, and on the manufacturer continuing to issue updates for your model. Sunsynk's Connect platform gives installers "remote firmware updates" alongside remote commissioning and troubleshooting, which reduces site visits and downtime⁷, so in most cases an update does not mean an engineer on the doorstep.

Raising a support ticket for an upgrade

The maker's stated route is simple: "Raise a Ticket for a Firmware Upgrade" through Sunsynk support¹. Live chat is also available "through your Connect app"¹. When you raise the ticket, be ready with the inverter model and the fault or behaviour you want addressed, since the support team will decide whether a firmware refresh is the right fix. If the matter is a complaint rather than a routine request, Flexi-Orb, the certification body associated with the brand, provides a complaint registration process that includes a file upload for supporting evidence⁸.

Most Sunsynk accessories require professional installation to maintain the system warranty and comply with Part P of the Building Regulations⁵, and the same principle of leaving technical work to qualified people applies to firmware: the two-set structure means a partially applied or mismatched update can introduce the very faults it was meant to cure³.

Over-the-air updates and the role of the data logger

The data logger is the box that connects the inverter to the outside world. Sunsynk's data loggers support "Over-the-air firmware updates" and pass data "securely to the Sunsynk cloud platform" from connected inverters, with support for RS485, Ethernet and Wi-Fi connections⁹. The wider data logger and monitoring gateway range adds "remote diagnostics capabilities" that the maker says reduce truck-roll costs for installers managing large fleets of installations¹⁰. The logger connects the inverter to the SolarmanV5 cloud platform, accessible via mobile apps for iOS and Android and a web portal⁵.

What this means for an owner is that the update path runs through the logger and the cloud, not through a cable and a laptop in the hallway. The dependence to be aware of is that over-the-air updates rely on the manufacturer's cloud platform remaining available for your model, a point covered more generally in firmware updates, app support and product lifespan.

Sunsynk Elite remote oversight and fault checking

The Sunsynk Elite range lists "Remote monitoring and diagnostics" among its features¹¹. The platform supports "installer-level access so your engineer can remotely diagnose issues without a site visit"⁵, and the data logger range enables "real-time remote monitoring for both homeowners and installers"⁹. For the householder this is the practical payoff of the connected architecture: a fault can often be identified, and a firmware refresh applied, without anyone travelling to the property. The trade-off is that this convenience depends on the inverter being connected to the maker's cloud, and on the app and platform continuing to be supported.

Sunsynk in the UK: the company behind the inverters

Sunsynk describes itself as "trusted by installers in over 40 countries"¹², with offices in Australia, the Canary Islands, Hong Kong, Poland, South Africa, the United Kingdom and the USA¹⁰. The UK office is at Unit 8, Total Park, Bennetts Lane, Shell Green, Widnes WA8 0GW, phone +44 151 832 4300⁶, and the same number is given for the UK technical support team⁵. The UK range covers single-phase systems from 3.6kW to 8kW for residential use, three-phase systems from 8kW to 12kW for larger homes and light commercial premises, and high-voltage commercial inverters from 20kW to 50kW¹³. Accessories are sold through Sunsynk-approved distributors and installers throughout the UK⁵. More on the company and its products is in our Sunsynk hybrid inverters and batteries page, and on the wider market in solar inverter manufacturers.

Secondhand cells, battery compatibility and DC bus faults

Firmware and battery compatibility are linked, because part of what updates deliver is "compatibility updates"¹. Sunsynk inverters are optimised for Sunsynk LiFePO4 batteries and are guaranteed compatible across the entire Sunsynk battery range, with many models also supporting third-party batteries via CAN bus or RS485¹³. The Fogstar compatibility list records Sunsynk under the Pylontech Protocol¹⁴, and the All-In-One Elite offers RS232, RS485 and CAN communication¹⁵. Sunsynk's own low-voltage batteries include the X Series and L Series modules¹⁶.

A DC bus voltage fault is the kind of issue that should go through the support ticket route rather than a DIY fix. The support team can diagnose remotely, and refreshing the firmware is one of the tools they may use, since incompatible firmware pairings are a known cause of misbehaving readings⁴. Secondhand battery cells are a separate risk: pairing cells of unknown history with an inverter whose firmware expects a particular protocol is exactly the situation where compatibility updates and a support ticket matter most. The maker's accessories range is selected to work seamlessly with Sunsynk inverters and batteries, removing the guesswork from component selection⁵.