In article ,
Chris J Dixon wrote:
critcher wrote:

had a repair chap in the other day to change 3 way valve and actuator.
He reckons I could save £200 pa on my gas bill by changing to a combi
boiler.
My system is a condensing Vaillant boiler with hot water provided by hot
water storage cylinder.
Don't like the pressurised systems, seems to many problems highlighted
on here.

How did he make his "calculation"?

Did you tell him what your existing gas bill is? What percentage
saving does this represent? Don't include the standing charge.

Using some rough figures, £200 would buy me around 6500 kWh of
gas which is equivalent to a constant consumption of about 740 W,
which is somewhat high for cylinder losses.

You also have to add in the costs of the new unit and fitting (unless the
old is worn out), written down over its expected lifetime. Likely more
than 200 quid a year.

--
*Dancing is a perpendicular expression of a horizontal desire *

Dave Plowman London SW
To e-mail, change noise into sound.