Solar PV Health Check

An assessment, not a sales visit

A health check produces a report. It does not produce a quotation unless you ask for one afterwards, and the report says what it says regardless of whether there is work in it for us.

That distinction matters because most people asking for one are in a position of not knowing what they have. They bought a house with panels on it, or they inherited a system from a company that no longer exists, or they have suspected for two years that the array is not doing what it was supposed to.

The paperwork question

The first thing we look at is what documentation survives. For an existing installation the set should include an MCS certificate, an Electrical Installation Certificate, the DNO notification or G99 approval, warranty registrations, and any export or Feed-in Tariff agreement.

MCS certification matters beyond tidiness: it is the basis on which an installation qualifies for a Smart Export Guarantee tariff. A system with no MCS certificate can still be perfectly good, but it will be harder to place on an export tariff, and that is worth knowing before you assume an income.

Where paperwork has gone missing we tell you what can realistically be reconstructed and what cannot. Some of it can be recovered from the certification body or the network operator; some of it cannot be recovered at all.

What we inspect

The physical inspection covers the array and its interface with the roof — fixing method, whether hooks landed in rafters, whether the covering was relieved properly, clamp condition, rail alignment and any movement. Then the DC side: cable routing and support, UV condition, connector types and whether mixed brands have been mated, and the state of any rooftop isolator.

Inside, the inverter is inspected for its siting, ventilation, event history and configured settings. Protection settings on older inverters sometimes do not match what is currently expected, and it is worth checking. The consumer unit connection, isolation arrangements and labelling are assessed against what an electrician arriving in an emergency would need to find.

What we measure

Testing gives the report its weight. String open-circuit voltages compared against each other and against the design. Operating currents corrected for conditions. Insulation resistance on the DC circuits. Earthing and bonding continuity. Where per-panel monitoring exists, a module-by-module review.

Alongside that we model what the roof should produce, using its actual orientation, pitch, array size and measured shading, and compare it against whatever generation history is available. A system producing well below expectation with no electrical fault usually has a shading, soiling or configuration explanation, and the data narrows it down.

The report

You get a written document with photographs, organised by urgency rather than by component. Anything with a safety implication is flagged first. Then defects affecting performance or longevity. Then observations worth knowing but not worth acting on yet.

Each finding says what it is, why it matters, and roughly what it would take to put right. Where the sensible answer is to do nothing, the report says that too. And where a system turns out to have been well designed and properly installed, that is a useful thing to have written down — particularly if you are about to buy the house it sits on.