Hardware · Case file
Sunsynk hybrid warranty, backup and who you call
Updated
Flexibility attracts widely varying installers. A tidy install with a proper export limit and a labelled essential-load board is the product.
The ownership question
A cheap inverter on a messy board is not. You may have an inverter warranty from one place and a cell warranty from another. Get both names on paper. Many Sunsynk installs can be specified with an essential-load output. It is not present unless the quote says which circuits move to that output.
Who it still suits: confident buyers who want a known hybrid platform, rack batteries and an installer who programs time-of-use charging properly.
A September 2026 figure for Sunsynk hybrid
Take a 10 kWh pack, cycled about 260 times, at 90% round trip. Charge at 13.0p, and value what comes back at 26.0p. Export given up is priced at 4.0p. There are no panels beside this 10 kWh pack, so every unit charged comes off the grid. Delivered energy is about 3159 kWh. After charging cost and lost export, the figure saves about £365 a year. Set that against £6,285 fitted, which is a September 2026 illustration at the temporary 0% residential rate, not a quote. That is a simple payback of about 17.2 years, which is past a typical 10-year warranty. Nudge the night rate up by 4p and see if you still like it.
In most single-phase houses in Britain, 5 kW sits above the 3.68 kW G98 line, so this wants a G99 application before anyone energises it. Export can still be capped. Agree that before the inverter is ordered. The figure uses 10 kWh and 0 kWp, which is enough to tell two quotes apart if they assumed something else.
At a steady 600 W evening load, 10 kWh lasts about 16.7 hours. A 3 kW kettle only works if the inverter can deliver it. Capacity on the badge does not answer that.
VAT, paperwork, refusal
Where the job is a qualifying install in a home, the 0% rate runs to 31 March 2027 and is due to become 5% after that. This figure prices the work at £6,285 on that basis. It does not apply to a shop, and it does not apply to a battery you buy and fit yourself.
I would not treat backup as included on a 10 kWh quote unless the circuits are listed.
If you already own Sunsynk hybrid, do not rip it out because a headline frightened you. Photograph the serial, keep the installer details, and ask them what the warranty path is this month.
Common questions
Is the price on this page a quote?
No. £6,285 is a September 2026 illustration for a 10 kWh example at the temporary 0% residential rate. Your survey replaces it.
Will it stay on in a power cut?
Only if a gateway or essential-load board was designed and paid for. A standard grid-tied battery turns off with the grid. On this 10 kWh example the inverter is 5 kW, and backup is still a separate line.
What paperwork should I keep?
Keep the MCS certificate where the job is certified, the electrical certificate, the DNO record, the schematic, the warranty registration and a photo of the schedule. For an illustrated £6,285 job, that folder is part of what you bought.
What if the cheap rate is not 7p?
Then the figure changes. This page used 13.0p as a charge rate and 26.0p as the rate avoided. A smaller gap means a worse payback. Read the live tariff.
Sources
Want a price for your house?
The figures above are a rough guide. An installer still needs to see your fuse board, where the battery will go, and whether you want power during a blackout.