endymion wrote:

snip

I am absolutely certain nothing else is getting hot or seems to be
switched on. I have a fridge, freezer and one low energy light bulb
( 60 equivelent in normal lights) running all night. The dishwasher is
programmed to come on at 4,00 am and wash up for an hour and the
immersion heater is time switched for two hours each night. All of
these (and a washing machine twice a week) have used no more than 17
units overnight every night for the last six weeks.

The day usage ( when I am out anyway) stands steady at about 5 units (
unless I cook a lot in which case it goes up to 10 units) .

When I put the heater on last night it went up to 82 units used in off
peak time. Nothing different on.


The 17 units figure seems suspiciously high. Without storage heating or
an immersion heater, we average less than 4 units per night - and this
includes two freezers, a fridge, and dishwasher and washing machine
(both elderly) each run, say, 4 times/week.

Add in your 2 hours of immersion heater, 6 kWh if the thermostat doesn't
kick in, and it would still only come to less than 10 units.

Our daytime use pattern is sufficiently different to yours that
comparison is much harder, but we average 9.5 units/day in summer, which
includes the freezers, PC all day, power tools, electric oven, etc.

As others have suggested - time to check the meter with a known simple
load and _everything_ else turned off - even the fridge and freezer for
an hour.

--
Kevin Poole
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