Installing and maintaining solar water heating
Once you choose the right solar water heating system for your needs, it must be well installed and maintained so you get the best performance out of it.
Installation and consents
Installations need to comply with the requirements of the New Zealand Building Code and you will need a building consent from your local council. Find their contact details on the local council's website.
It's the homeowner's legal responsibility to make sure the required building consents are obtained. However, your installer should assist you with this.
Some councils offer zero or reduced consent fees, or other incentives to encourage solar water heating and other renewable technologies.
Maintaining your solar water heating system
Your system should require little maintenance but there are some things you can do to keep it running at its best. Manufacturer's instructions should be followed for any maintenance issues or requirements over the life of the system.
- solar hot water tanks should be maintained in a similar way to normal electric hot water tanks. Flush the Temperature/Pressure relief valves on the hot water tank (if you have them) every six months. Glass-lined water containers should have their anode changed every five years - more frequently in hard water areas
- wash collectors if they get dirty
- if the system uses glycol or a water-glycol mixture, this will need replacing periodically. See the manufacturer's instructions for details.
Also periodically check you collectors for the following and contact your retailer with any concerns:
- leaks in the collector case, glass or pipes. Condensation on the glass or wet insulation indicates a possible leak
- any discolouration or corrosion
- the indicators on evacuated tubes that let you know if the integrity of the vacuum is maintained
- shading and debris - nearby trees may have grown to shade your collectors without you noticing any broken glass or damaged glazing. Any water coming in will rapidly deteriorate the absorber's surface and insulation
Frost protection methods that use frost plugs (which are increasingly rare) sometimes need resetting after freezing conditions.
Make sure your retailer or installer gives you clear, detailed operating instructions when they install your system.
Your solar water heating system should perform well if:
- it is the correct design for your location
- it is the appropriate size for your household, and
- it has been properly installed.
If your system isn't working as well as you'd like, go back to the retailer who sold it to you. If you are still not satisfied, you can contact the Solar Association of New Zealand if the system's supplier is accredited by the Solar Association.
If the supplier is not SIA-accredited, or the problem occurs after the manufacturer's warranty has expired, you are still covered by the Consumer Guarantees Act. This covers both manufacturing defects and lack of skill by the installer. The Fair Trading Act covers you if your system isn't performing as well as you were told it would.