How to Hire a Trusted Solar Diverter Installer in 2026 (UK)
A good solar diverter installer is MCS- or NICEIC-registered, has fitted your chosen diverter model many times, and gives you a clear written quote and commissioning certificate. Diverters like the myenergi eddi, Solar iBoost+ and Apollo Gem route surplus PV power into your immersion tank instead of exporting it for pennies. A bad install can leave the unit miswired or the CT clamp on the wrong cable — here is how to avoid that.
Why solar diverter installer choice matters
A diverter is a deceptively simple device but the install touches the consumer unit, the immersion circuit and a current-clamp on the live grid feed. Get any of these wrong and the unit either does nothing, drives the immersion in error, or interferes with the export meter. A diverter install is also notifiable Part P work in most cases — so it must be self-certified by a registered electrician or MCS-accredited solar firm.
What to check before you compare quotes
1. MCS or NICEIC registration
If a diverter is added at the same time as a new PV system, the install must be MCS-certified to keep your export tariff. Standalone retrofits should be done by a Part P-registered electrician (NICEIC, NAPIT or ELECSA).
2. Model-specific experience
Ask the installer how many eddi, Solar iBoost+, Apollo Gem or Marlec SOLiC units they have fitted in the last year. Each has different wiring and commissioning quirks.
3. Public liability cover
Ask for proof of at least £2m public liability — standard for any sub-contractor on a solar job.
What a good diverter quote includes
A complete written quote should list: the diverter model, CT clamp(s), immersion tail and isolator if needed, MCB or RCBO upgrade if the consumer unit is full, app pairing and commissioning, and the warranty registration in your name. Ask about boost mode and integration with battery storage or EV chargers (eddi pairs with zappi automatically).
How to compare three quotes fairly
Send all three installers the same written scope: tank type and rating, distance from consumer unit to tank, distance to grid meter, whether existing PV inverter is online, and whether you want app/Wi-Fi commissioning. Quotes that vary by more than 25% usually differ on scope, not skill.
FAQs
Related guides
Get 3 Free Quotes — Vetted UK Solar Diverter Installers
BestBuilders matches you with up to 3 MCS or NICEIC-registered installers. Compare quotes — no cost, no obligation.