ECONOMY 7 HOT WATER NOT WORKING

[ns3270]

Just electric in the house - no gas.
I have 2 switches in the airing cupboard, one for the immersion heater to heat the hot water (which works fine), and the other one also to heat the hot water overnight using Economy 7 night rate. This one doesn't work - any ideas?

 

[leakydave]

Check fuse... or replace the element

 

[ns3270]

Is there any chance it could just be the thermostat which is much easier to change than the element?
Is the element likely to be a standard one that I could get from B&Q or are they all specific?
I guess I have to drain the system to replace the element - is it an easy job?

 

[leakydave]

Up to you, normally I would change both as a matter of course. Its easy if the old one comes out without too much fuss. Once the cylinder is drained you will need the right tool to get it out, a little heat can help, and even if you try and tighten it a bit to break the seal to undo it. Not the sort of job to start at half 3 on a saturday afternoon. I guess you have the element low down across the cylinder, so get one that will fit! Plenty of PTFE and jet blue sealer on the threads, don't overtighten... and make sure you don't cross thread it like I did once... Fill the cylinder slowly and check for leaks. Better to find a leak with only 12" of water in the cylinder. Good luck.