02/15/2017
Annual solar hot water system check-ups help you keep your solar system running efficiently. USING AN ANTIFREEZE SOLUTION
Solar water heating systems that use an antifreeze solution (propylene glycol or ethylene glycol) as a heat-transfer fluid have effective freeze protection as long as the proper antifreeze concentration is maintained. Antifreeze fluids degrade over time and normally should be changed every 3–5 years. Since these systems are pressurized, it is not practical for the average homeowner to check the condition of the antifreeze solution. If you own this type of system, have a solar heating professional check it periodically. Collector shading
Visually check for shading of the collectors during the day (mid-morning, noon, and mid-afternoon) on an annual basis. Shading can greatly affect the performance of solar collectors. Vegetation growth over time or new construction on your house or your neighbor's property may produce shading that wasn't there when the collectors were installed.
Collector soiling
Dusty or soiled collectors will perform poorly. Periodic cleaning may be necessary in dry, dusty climates.
Collector glazing and seals
Look for cracks in the collector glazing, and check to see if seals are in good condition. Plastic glazing, if excessively yellowed, may need to be replaced.
Plumbing, ductwork, and wiring connections
Look for fluid leaks at pipe connections. Check duct connections and seals. Ducts should be sealed with a mastic compound. All wiring connections should be tight.
Piping, duct, and wiring insulation
Look for damage or degradation of insulation covering pipes, ducts, and wiring.
Roof penetrations
Flashing and sealant around roof penetrations should be in good condition.
Support structures
Check all nuts and bolts attaching the collectors to any support structures for tightness.
Pressure relief valve (on liquid solar heating collectors)
Make sure the valve is not stuck open or closed.
Dampers (in solar air heating systems)
If possible, make sure the dampers open and close properly.
Pumps or blowers
Verify that distribution pumps or blowers (fans) are operating. Listen to see if they come on when the sun is shining on the collectors after mid-morning. If you can't hear a pump or blower operating, then either the controller has malfunctioned or the pump or blower has.
Heat transfer fluids
Antifreeze solutions in liquid (hydronic) solar heating collectors need to be replaced periodically. It's a task best left to a qualified technician. If water with a high mineral content (i.e., hard water) is circulated in the collectors, mineral buildup in the piping may need to be removed by adding a de-scaling or mild acidic solution to the water every few years.
Storage systems
Check storage tanks, etc., for cracks, leaks, rust, or other signs of corrosion. Call us for a checkup. 503-449-0527
