Solar systems are famously low-maintenance — but "low" isn't "zero." Soiling alone can cost 3–7% of annual production, and a silently failed optimizer or microinverter can cost far more. This checklist covers everything a well-maintained system needs in 2026, whether you do the monitoring yourself or hand it all to a pro.
Monthly: 5-minute monitoring check
- Open your monitoring app and compare this month's production to the same month last year. A drop of more than ~10% (weather-adjusted) deserves investigation.
- Look for error flags on the inverter or individual panels.
- Glance at your electric bill. An unexplained increase is often the first sign of underproduction.
Quarterly: visual ground check
- Scan panels from the ground for visible debris, bird nests, or staining
- Check that the inverter status lights are normal (green, no fault codes)
- Look for new shading — trees grow, and a branch that didn't matter two years ago might now shade a panel for hours a day
Annually: professional inspection
Once a year, have a qualified technician perform a full inspection. A proper professional maintenance visit should include:
- Electrical connections: torque checks on terminals, inspection for corrosion or rodent damage
- Panel condition: checking for microcracks, hotspots (ideally with thermal imaging), and delamination
- Inverter health: error log review, cooling fan check, firmware updates
- Roof attachments: flashing and sealant condition at every mount point
- Racking: checking for loosened hardware after a year of thermal cycling and wind
- Production audit: comparing actual output against design estimates
Expect to pay $150–$400 for a thorough inspection. Compare that to a single failed-and-undetected string costing you hundreds per year in lost production.
As needed: cleaning
Whether panels need professional cleaning depends heavily on where you live:
- Desert Southwest (Phoenix, Las Vegas): dust and monsoon debris justify 1–2 cleanings per year
- Agricultural areas: harvest dust and pollen build up fast
- Rainy climates: rain handles most of it; clean only when production dips
- Coastal areas: salt film benefits from periodic rinsing
Never pressure-wash panels or clean them with abrasives — both can void manufacturer warranties.
Watch for pest damage year-round
Pigeons nesting under panels and squirrels chewing wiring are among the most expensive "small" solar problems. Droppings, nesting material at panel edges, and scratching sounds are early warnings. Critter guards are a one-time fix that prevents thousands in wiring repairs — see our complete critter guard guide.
Special situations
- After severe weather (hail, high winds): schedule an inspection even if everything looks fine from the ground.
- Orphaned systems: if your installer closed, start with a full system audit to establish a documented baseline, then move to annual maintenance.
- Before your inverter warranty expires: have the inverter checked in its final warranty year — if it's marginal, better to claim now.
The payoff
A maintained system produces more, lasts longer, and holds documentation that protects your warranties and your home's resale value. If you'd rather never think about any of this, find a vetted maintenance pro near you and put it on autopilot.