On Fri, 16 Jan 2009 21:52:11 +0000, Stephen wrote:

Unfortunately, rather than have one big immersion heater going down
from the top, my cylinder has two smaller immersion heaters: one near
the bottom and one higher up. To check the bottom one would require
draining most of the water.

No just take drain enough to remove the top one and use a torch and small
mirror. I guess these two go into the sides as an E7 setup.

Do you mean reheat by immersion heater or reheat by boiler?

I was thinking via a boiler as E7 had not been mentioned before. Nothing
like leaving pertinant facts out to get duff answers in return.

We do use economy 7 with the immersion heaters so I have no idea whether
it takes seven minutes or seven hours. I will have to try to reheat
during the day when I am awake to monitor it.

Not sure how you'll tell then unless there is some indication when the
stats in the immersions have opened. Which isn't usual. Running water out
to see how hot it slows down the reheat as you are introducing more
cold...

--
Cheers
Dave.