Hi Ian,
Thanks for this, you're right about the protech thing. Havig turned one off earlier it appears the top line is still quite warn, the bottom one was cold and leaking very very slightly. I presume I had turned off the overnight supply?
I'm not sure what mosel it is, according to the manual it is an unvented hot water storage cylinder, but its a contract STD model.
I'm still confused as to why the lights remain on whether or not the switches are on, although I guess this may just signify whether there is hot water? Is it safe to turn both switches off during the day, and just put the thing on overnight?
Also, if they are both immersions can I turn them off and if I do, how long would the water take to warm up again. The boiler is not connected to the heating so does it make sense to mostly keep the immersions off?
I don't have a chaeper electricity period either I don't think, its just a flat 11p per kwh.
Is this any more help?
Thanks
Ian