On Fri, 02 Sep 2005 15:00:08 +0100, "Dave Plowman (News)"
wrote:

In article ,
Pete C wrote:
Out of curiosity I calculated how much gas my boiler pilot light
consumed and took a meter reading at 9pm and again at exactly 9pm the
next day. The heating & water have been off all that time with just the
boiler pilot light lit. I included the 2 red decimal numbers in the
meter readings and in 24hrs it had used 0.18 unit, which over a year is
65.70 units. If my sums are correct (Calorific Value of 39.4) I work
that out to be around 2081kWh. Is that amount of consumption about
right for a pilot light? On 2p per kwh that would be around £41 a year.
The boiler is a Potterton Prima B about 6 years old.

Over 15 years that could pay for a condensing boiler....

But the calculation is flawed by making it at this time of the year with
the boiler not in use. For the 6 months or so of the year when the heating
is needed - or it's used for just heating hot water - all that energy
won't be wasted. There's probably a diversity calculation that takes this
into account.

What happens when the pump is running but the boiler isn't firing on
an old style boiler, I'd have thought there are convection losses up
the flue? Maybe worth another condensing boiler over 15 years...

cheers,
Pete.