Selfsufficientish.com

G'Day Guys,

We have a flat plate, electrically boosted system that is gravity flow, themosyphon circulation that does not use a heat exchanger. It is about 25 years old and so does not owe us much. It cost about 3x as much as a gas system when we bought it. One thing with the flat platers is keeping the glass surface clean otherwise you lose efficiency. We rarely use the booster in summer and every few days in winter, depending on the weather. The tank is 300 gal.

Nev

Cheers Gug for the reminder about keeping the panel below the pipe surface , this bit I had forgotten.
Though I had assumed that with the panel getting hot , and pressurised the cooler water under the earth might flow into the panel anyway. Cold to hot principal. But you're right better to have it below.

Hi, all I've been reading all your ideas with interest as I am in the plans and costing stage of a hot water system with a combi boiler to run along side solar panels. The main problem I have come across is to ensure the water heats to a reasonable temp. 60 deg. on overcast days to cut out the legionella factor. I've decided on an adapted cylinder immersion switch to trigger the circulating pump when it reaches 60 deg. this is all set up in a vented system with an indirect cylinder. The hot water supply from the boiler will have a double check valve and stop cock and the same with the supply from the solar system so that you turn one off and the other on. Nice days solar hot water, bad days gas fired combi hot water. Can anyone give me any pointers? For advice on building solar panels check out the bigginhill website. Cheers.