On 05/06/2011 00:09, Tabby wrote:
On Jun 4, 12:55 pm, wrote:
On Fri, 03 Jun 2011 23:13:31 +0100, geoff wrote:
I'll send it on monday if I remember

It's OK, boiler's running now and I suggested to punter he gets new one
ordered up from ****ty Plumbing. Just annoying not to be able to find
vanilla Wilos any more. I'd have stocked up if I'd known they were going
to disappear.


I dont have a smartpump to get the figures from, so these figures are
likely inaccurate...


Cold winter day: 33% run time
summer: almost no use for 4months
8 months 0-33%, ave 16.6% of time - over the whole yr, 11% of the
time

plain pump:
so a 30w non-electronic pump will use about £3.30 per yr in leccy, £33
per decade, £83 per 25 year CH system life

TCO per 25 yrs is thus £25+£83 = £108


smartpump:
vague guess halved energy use - £42 per 25yr life
TCO thus £126+42 = £168

Comments welcome!

You've missed that the inefficiency produces waste heat, which is of
course not wasted at all, because you wouldn't be running the pump if
you didn't want heat!

SteveW