I have decided my Ideal Icos HE18 is beyond sensible repair cost, I
have chucked enough at it, so I am looking now for a replacement...

It needs to be a regular, vented system type boiler, but if possible
with separate boiler output temperature controls when heating the hot
water tank, to that when heating the radiators. Yes I presently have a
room stat and a water tank stat. I just like the hot water to be able
to be very hot 80C, I appreciate that is above the efficient condensing
range, but to heat the radiators the boiler output temperature need not
be quite so hot. 18+ Kw needed as present boiler is adequate. The
predecessor to that was around 32Kw, but some good insulation has made
that high an output unnecessary.

I had no input into the boiler make last time around, this time I am
looking to Vailant or Worcester/Bosch for a more reliable boiler.

On 24/03/2018 19:25, Harry Bloomfield wrote:
I have decided my Ideal Icos HE18 is beyond sensible repair cost, I have
chucked enough at it, so I am looking now for a replacement...

It needs to be a regular, vented system type boiler, but if possible
with separate boiler output temperature controls when heating the hot
water tank, to that when heating the radiators. Yes I presently have a
room stat and a water tank stat. I just like the hot water to be able to
be very hot 80C, I appreciate that is above the efficient condensing
range, but to heat the radiators the boiler output temperature need not
be quite so hot. 18+ Kw needed as present boiler is adequate. The
predecessor to that was around 32Kw, but some good insulation has made
that high an output unnecessary.

I had no input into the boiler make last time around, this time I am
looking to Vailant or Worcester/Bosch for a more reliable boiler.

I've a Vaillant Greenstar of some sort, it has separate controls for hot
water and radiators but TBH I'm not sure how it works. All the manuals
are easy to download.

I have a simple W plan and IIRC the diverter is switched by the cylinder
stat. Don't know if the boiler temperature is controlled at the same
time with the default "simple" control system.

Boiler has been very reliable.

newshound wrote:
On 24/03/2018 19:25, Harry Bloomfield wrote:
I have decided my Ideal Icos HE18 is beyond sensible repair cost, I
have chucked enough at it, so I am looking now for a replacement...

It needs to be a regular, vented system type boiler, but if possible
with separate boiler output temperature controls when heating the hot
water tank, to that when heating the radiators. Yes I presently have a
room stat and a water tank stat. I just like the hot water to be able
to be very hot 80C, I appreciate that is above the efficient
condensing range, but to heat the radiators the boiler output
temperature need not be quite so hot. 18+ Kw needed as present boiler
is adequate. The predecessor to that was around 32Kw, but some good
insulation has made that high an output unnecessary.

I had no input into the boiler make last time around, this time I am
looking to Vailant or Worcester/Bosch for a more reliable boiler.

I've a Vaillant Greenstar of some sort, it has separate controls for hot
water and radiators but TBH I'm not sure how it works. All the manuals
are easy to download.

I have a simple W plan and IIRC the diverter is switched by the cylinder
stat. Don't know if the boiler temperature is controlled at the same
time with the default "simple" control system.

Boiler has been very reliable.
Isn't Greenstar a WB model name?

On 24/03/18 20:32, Bob Minchin wrote:

Boiler has been very reliable.
Isn't Greenstar a WB model name?

Yes.

On 24/03/2018 20:32, Bob Minchin wrote:
newshound wrote:
On 24/03/2018 19:25, Harry Bloomfield wrote:
I have decided my Ideal Icos HE18 is beyond sensible repair cost, I
have chucked enough at it, so I am looking now for a replacement...

It needs to be a regular, vented system type boiler, but if possible
with separate boiler output temperature controls when heating the hot
water tank, to that when heating the radiators. Yes I presently have a
room stat and a water tank stat. I just like the hot water to be able
to be very hot 80C, I appreciate that is above the efficient
condensing range, but to heat the radiators the boiler output
temperature need not be quite so hot. 18+ Kw needed as present boiler
is adequate. The predecessor to that was around 32Kw, but some good
insulation has made that high an output unnecessary.

I had no input into the boiler make last time around, this time I am
looking to Vailant or Worcester/Bosch for a more reliable boiler.

I've a Vaillant Greenstar of some sort, it has separate controls for hot
water and radiators but TBH I'm not sure how it works. All the manuals
are easy to download.

I have a simple W plan and IIRC the diverter is switched by the cylinder
stat. Don't know if the boiler temperature is controlled at the same
time with the default "simple" control system.

Boiler has been very reliable.
Isn't Greenstar a WB model name?


Oops yes I mean ecoTEC! But WB and Vaillant seem to rate equally highly
both here and in Which?

On 24/03/18 19:25, Harry Bloomfield wrote:
I have decided my Ideal Icos HE18 is beyond sensible repair cost, I have
chucked enough at it, so I am looking now for a replacement...

It needs to be a regular, vented system type boiler, but if possible
with separate boiler output temperature controls when heating the hot
water tank, to that when heating the radiators. Yes I presently have a
room stat and a water tank stat. I just like the hot water to be able to
be very hot 80C, I appreciate that is above the efficient condensing
range, but to heat the radiators the boiler output temperature need not
be quite so hot. 18+ Kw needed as present boiler is adequate. The
predecessor to that was around 32Kw, but some good insulation has made
that high an output unnecessary.

I had no input into the boiler make last time around, this time I am
looking to Vailant or Worcester/Bosch for a more reliable boiler.

I heavily researched Viessman and Worcester Bosch:

I went with WB, but I would not be that unhappy with Viessmann either.

Pros and cons (WB substantiated, Viessmann is based off anecdotal
evidence and on paper specs - at least one person here has a Viessmann
and will probably comment)


WB:

1) Highest DHW output for a wall mounted unit;
2) Reasonable price;
3) Easy to wire and operated (either dumb knobs or LCD depending on model)
4) Quiet and well behaved;
5) According to my Gas Fitter, WB parts are quicker to get hold off than
Viessmann, maybe because it's more common???? *Anecdotal*


Viessmann:
1) Weather compensation that WB don't have (unless you buy their fancy
controller that precludes using your own controls) - you only need add
the sensor to a north wall (or shaded area I assume);

2) Slightly more "Waitrose" than WB's "Sainsbury" - stainless heat
exchanger supposed to be a selling point.


I went WB mostly because it had enough DHW power in theory to run a
shower and a bath (latter is throttled to 20l/min by flow restrictors).


I do miss not having weather comp, but I have measured the flow and
return temps for each number on the knob - and have a rough manual scale
of "this time of year, turn knob to 4" kinda thing.

It happens that Tim Watts formulated :
I went WB mostly because it had enough DHW power in theory to run a shower
and a bath (latter is throttled to 20l/min by flow restrictors).

I don't want/need DHW, I like stored HW.

On 24/03/18 20:48, Harry Bloomfield wrote:
It happens that Tim Watts formulated :
I went WB mostly because it had enough DHW power in theory to run a
shower and* a bath (latter is throttled to 20l/min by flow restrictors).

I don't want/need DHW, I like stored HW.

Well then - look at there non combi range - most of the Pros and cons
are likely to be much the same. But you could easily look at the
Viessmann with weather comp.

In message , Tim Watts
writes
On 24/03/18 20:48, Harry Bloomfield wrote:
It happens that Tim Watts formulated :
I went WB mostly because it had enough DHW power in theory to run a
shower and* a bath (latter is throttled to 20l/min by flow restrictors).
I don't want/need DHW, I like stored HW.

Well then - look at there non combi range - most of the Pros and cons
are likely to be much the same. But you could easily look at the
Viessmann with weather comp.

:-) I have just fired up a 30kW Viessmann in the cottage. I'm not yet
familiar with the controls. Weather comp yes. Different temps. for hot
water and heating, yes I think. You can certainly switch off the heating
for summer. Clear display.

I have a 30kW condensing boiler and new flue for anyone offering an
appreciative home. 5 years old (2 years work and 3 resting). Potterton
precision.

--
Tim Lamb

Tim Lamb wrote on 24/03/2018 :
:-) I have just fired up a 30kW Viessmann in the cottage. I'm not yet
familiar with the controls. Weather comp yes. Different temps. for hot water
and heating, yes I think. You can certainly switch off the heating for
summer. Clear display.

I cannot seem to see a name for the independent boiler output
temperature limiting - anyone, what is it called?

Is it available on a regular, open vented boiler?

On 24/03/2018 19:25, Harry Bloomfield wrote:
I have decided my Ideal Icos HE18 is beyond sensible repair cost, I have
chucked enough at it, so I am looking now for a replacement...

It needs to be a regular, vented system type boiler, but if possible
with separate boiler output temperature controls when heating the hot
water tank, to that when heating the radiators. Yes I presently have a
room stat and a water tank stat. I just like the hot water to be able to
be very hot 80C, I appreciate that is above the efficient condensing
range, but to heat the radiators the boiler output temperature need not
be quite so hot. 18+ Kw needed as present boiler is adequate. The
predecessor to that was around 32Kw, but some good insulation has made
that high an output unnecessary.

I had no input into the boiler make last time around, this time I am
looking to Vailant or Worcester/Bosch for a more reliable boiler.


Vaillant 400 series do vented and split temperature operation. They can
also do weather compensation if you want. Been very pleased with my 600
series system boiler so far...

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

John Rumm laid this down on his screen :
Vaillant 400 series do vented and split temperature operation. They can also
do weather compensation if you want. Been very pleased with my 600 series
system boiler so far...

Thanks, I will take a look at those. I just to be armed for when a guy
comes around to give a quote..

In article ,
Harry Bloomfield wrote:
It needs to be a regular, vented system type boiler,

You might find a maker won't warrant an open vent type these days. And
many system boilers come with a pressure vessel installed.

--
*And the cardiologist' s diet: - If it tastes good spit it out.

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