"Alan Holmes" wrote in message
...

"Jodie" wrote in message
...
Have a nice new electrical greenhouse heater. Its set to automatically
start and stop with temperature.
So as to calculate power use and hence cost of greenhouse heating anyone
know of a good inexpensive system of recording the duration the heater
was actually on?

Connect a cheap electric clock in paralell with the heater, then all
you have to do is read the time!


But the clock won't be switched on and off by the thermostat if it's built
in to the heater.

At 10p per kw/h, a 1.5 kw heater (like mine) would cost about £3.60 if it
ran for 24 hours. It actually only runs to keep it just frost free which is
maybe 10 nights a year (? just a guess) and then it wouldn't run non-stop.
So I reckon about £15 a year maximum. Even if it's double that it would
probably cost more to find out.

If you're keeping it hot for orchids all year time then it might cost
significantly more...

--
Martin & Anna Sykes
( Remove x's when replying )
http://www.users.globalnet.co.uk/~sykesm