Chapter 5 of 615% of exam

Service, Operation, and Maintenance

Service and maintenance is 15 percent of the examination: evaluating PV and thermal systems and repairing or replacing components. The PrepPass CSLB C-46 Solar Study Guide covers this area in depth, with worked examples and a chapter quiz.

Evaluating PV

Compare measured output with an expectation, then test and inspect to find the difference.

Normal degradation

NREL's review found a median of 0.5% per year.

NREL, PV Degradation Rates

Soiling

Uneven soiling can cause hot spots; clean as the module maker recommends.

NREL O&M Best Practices

Ground faults

Often a wire rubbing a module frame.

NREL O&M Best Practices

Evaluating thermal systems

Most thermal faults are sensors, pumps, fluids, scale and leaks.

Pump runs at night

Suspect a shorted collector sensor or open tank sensor.

DOE Energy Saver (archived)

Glycol

Test pH and freeze point; change every 3–5 years.

DOE Energy Saver (archived)

Repair and replace

Repairs must keep equipment listings intact; storage repairs have their own rules.

ESS replacement

A replaced ESS is a new installation under the fire code.

2022 CFC 1207.3.8

Qualified persons

Only qualified persons maintain, remove or reinstall PV and storage.

County of San Diego PDS 081S

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