"Terry D" wrote in message
...
IMM wrote:
"Terry D" wrote in message
...
I have an old Potterton boiler with gravity hot water and pumped
heating. The system still works very well and seems reasonably
efficient (£25 monthly for a 4 bed detached). However, during the
colder months, I have far too much hot water at too high a
temperature. Would it be possible to add a thermostatically
controlled valve to the return from the hot water cylinder (thus
maintaining the vent on the flow pipe) in order to control the hot
water temperature. I have a 3-way motorised valve which I could use
by blanking one of the inlets, and then controlling it from a
cylinder stat. Would I also need a narrow bore by-pass.
You can fit a normal DHW blending valve to the cylinder draw-off
pipe, not blocking the open vent. hot in one port from the cylinder,
cold in the other. the outlet is blended to whatever you set it to.
They are in Screwfix or http://www.plumbworld.co.uk
Better still replace the old cast-iron clunker with a modern
condensing boiler with a fully pumped system. Your £25 per month
will be down to aprox £15 per months, saving £120 per year.
Does a condensing boiler necessarily
have to be wall mounted with a balanced
flue?
All domestic versions I have see, yes.
My old Potterton is nicely hidden away
in a cupboard with no access
to an outside wall and I want to keep
it that way.
Kestons can be fitted anywhere with the flue only being cheap plastic drain
pipe.
If I hadn't wasted £12 a
month for 20 years on a useless British Gas
service contract, I could now
replace my heating system twice over.
BG are not good at times.
Sorry, but I'm still really not
convinced about the apparent advantages
of condensing boilers,
Boilers are amongst the worst offenders when it comes to energy wasters in
your home. Boilers alone account for up to a third of all domestic CO2
emissions. If you don’t think your boiler should get away with it any
longer, then read on. As the current lifespan of a boiler is 10-15 years,
making the wrong decision about what boiler to have really could mean a life
sentence of wasting money and time and damaging the environment.
A heating system that uses a high efficiency condensing boiler and with the
correct heating controls can save as much as 40% on your fuel bills. It
really is time to shop your old boiler.
see:
http://www.saveenergy.co.uk/boilers/
At an alleged saving of £120 a year, it would
take 16 years to recoup my investment.
Your boiler will not last that long.
As I'm 60 now, I don't think I'll bother unless
I have to. I'm sitting here now at a nice comfortable
22 deg.C with a can of lager at 15 deg. :-) Cast
iron rules-OK.
Cast iron is very inefficient. Unless your house is heavily insulated, or
you turn rads off in many rooms, or you have a small house I can't see you
spending £300 on gas per year.
I would be very surprised if any owners
of four bed detached houses are
getting away with only £15 monthly
for gas heating.
That's what I pay, maybe less. I have a condensing boiler.
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