Why the South West's weather makes inspections worthwhile

Solar panels are remarkably durable. They sit on roofs for decades, shrug off frost and gales, and quietly turn daylight into electricity with almost no moving parts to wear out. That reliability can lull homeowners into thinking nothing ever needs checking, but a system in Devon, Cornwall, Somerset or Dorset faces a particular set of pressures.

Salt-laden air along the coast leaves a fine film on glass that dulls the light reaching the cells. Atlantic storms drive rain sideways into cable entries and mounting points. Mild, damp winters encourage moss, lichen and algae, while agricultural dust, tree sap and pollen settle on anything left long enough. Add seagulls, whose droppings are corrosive as well as unsightly, and it becomes clear that a solar array here benefits from the same routine attention you give a boiler or a gutter.

An annual inspection is not about expecting the worst. It is about catching small, cheap problems — a loose cable clip, a cracked pane, a nest forming under a rail — before they become expensive ones.

How often should you inspect?

For most domestic and commercial systems in the region, a sensible rhythm looks like this:

• Every 12 months: a full professional inspection covering electrical connections, mounting, inverter and performance.
• Every three to four months: a visual check from ground level, ideally with binoculars.
• After any named storm or severe weather: a quick look for displaced panels, debris or water staining.
• After roof work: scaffolding, chimney repairs and gutter clearing all create risks for panels and cabling.

Systems that are more than ten years old, or those on exposed coastal or upland sites, may warrant twice-yearly professional attention.

What you can safely check from the ground

You should never climb onto a roof to inspect panels. Falls are the single biggest danger, and walking on panels or the tiles around them can cause damage that costs far more than the inspection saves. Everything below can be done with both feet on the ground.

• Panel surfaces: look for cracked glass, discoloured cells, white snail trails across the surface or dark patches that suggest a failing cell.
• Debris and shading: leaves, moss clumps and overhanging branches can shade a whole string and hit generation hard.
• The inverter: check the display or app for error codes, and confirm the readings match what you would expect for the season.
• Your monitoring data: a gradual drop over weeks is the clearest early warning that something is wrong.
• Signs of wildlife: nesting material, droppings running down the glass or birds repeatedly landing at one end of the array.
• Below the roof: water staining on fascias, soffits or walls can point to a failed seal or a blocked cable entry.

What a professional inspection actually covers

A thorough inspection goes well beyond a glance at the glass. A competent technician will work through the whole system, from the panels to the isolators and the consumer unit.

• Wiring and connectors: MC4 connectors, DC cables and cable clips are checked for chafing, UV damage, corrosion and loose connections — all common causes of hidden faults.
• Mounting and fixings: rails, brackets and bolts are checked for corrosion, movement and correct torque.
• Inverter and isolators: enclosures are opened where appropriate to check for water ingress, insect nests, heat damage and correct labelling.
• Earthing and bonding: essential for safety and often overlooked on older installations.
• Performance testing: string voltages and currents, insulation resistance readings and, where available, thermal imaging to reveal hot spots invisible to the eye.
• Under-panel inspection: pest guards, nesting and debris build-up, which accelerate corrosion and can void warranties.

Warning signs that need prompt attention

Some issues can wait for the annual visit. Others should prompt a call straight away:

• A sudden drop in generation, or an inverter that keeps tripping.
• Error codes or warning lights on the inverter.
• Visible cracks, burn marks, browning or a smell of hot plastic.
• Buzzing, humming or crackling from the inverter or isolator.
• Panels that appear to have shifted, or rails that look misaligned or discoloured.
• Water dripping from beneath the array in dry weather.

Planning cleaning and repairs alongside the inspection

Cleaning and inspection pair naturally, because the cost of access is shared. Book a professional clean in spring, once the worst of the pollen and storm debris has passed, and have the inspection carried out at the same time. Cleaning should use purified water and soft brushes — never abrasives, pressure washers or household detergents, which can scratch the glass or damage edge seals. Early morning or late afternoon is best, when panels are cool.

Keep a simple log of every visit, reading and repair, along with your warranty documents and any MCS paperwork. If you plan to sell the property, that record is quietly persuasive evidence that the system has been cared for. And if an inspection turns up a fault, deal with it through a qualified installer rather than a general handyman — DC side work is not a job for the unqualified.