Use and maintenance

Problems

As long as the solar water heating system has been sized and installed properly, it should perform well. If not, go back to your installer and ask for the system to be fixed. After the maker's warranty has expired, you are still covered by the Consumer Guarantees Act for both manufacturing defects and lack of skill by the installer.

Maintenance requirements

A solar water heating system requires little maintenance, but, for maximum performance and energy savings, some maintenance is needed.

• Hot water cylinders should be maintained in a similar manner to normal electric hot water cylinders - hot and cold relief valves should be flushed every six months, and the anode in a glass-lined water container should be changed every five years (or more frequently in hard water areas). 
• Collector panels that are out of sight should occasionally be visually inspected for leaks, which may occur in the case, glass or pipes. Condensation on the glass or wet insulation indicates the system may be leaking. 
   
• Collector panels should be washed if they get dirty. This is usually a problem only if the panels are protected from the rain or during long dry periods, near dusty roads or when pollen levels are high.
   
• Check for shading at the same time - trees may grow unnoticed. Debris or bird droppings may gather on or around the collector panel, reducing solar absorption.
   
• Although not common, broken glass or damaged glazing should be replaced immediately as water coming in will cause rapid deterioration of the absorber's surface and insulation.
   
• Frost protection methods that use frost plugs (which are increasingly rare) sometimes need resetting in freezing conditions. If the system uses glycol or a water-glycol mixture, this should be replaced about once every five years, according to the manufacturer's instructions.
   
• Manufacturers' instructions should be followed for any maintenance issues or requirements over the life of the system. Make sure you are given adequate operating instructions when your system is installed.
   
• If there is any discolouration or corrosion, discuss this with your supplier or installer. 

More information

• EECA (Energy Efficiency and Conservation Authority) www.energywise.govt.nz
• For information on the EECA financial assistance programme www.energywise.govt.nz
• Compare electricity prices at www.powerswitch.org.nz
• For information about building, renovating and maintaining houses www.consumerbuild.org.nz

Download a copy of this report in PDF format here.

About PDFs
To view this document as a PDF you will need Adobe Acrobat Reader software installed on your computer. If you don't have this software, it is available free from Adobe.