New boiler ideas - spoilt for choice

[spacey3]

The Kingfisher II my parents have has finally given up the ghost, and the hot water cylinder has started to leak.

They want to go to a system boiler with an unvented cylinder. We have been looking at a Bosch Worcester Greenstar 30Cdi, Viessmann 200W, Atag 320s, or a Valiant 637.

We are leaning towards either the Viessmann or the Bosch at present (anyone have any thoughts on these four models?)

Also I have a question about moving the boiler, currently the Kingfisher is floor standing in the kitchen behind a cupboard. To move it the only ideal place is in an airing cupboard further in the bungalow. The problem is that all the pipes are in-cased in concrete so would be a major job to dig things up.

The preference would be as little disruption as possible - If you move the boiler it would require mains water, which is easy enough to reroute, also the gas is outside the new space so not too much of a problem. The issue would be reconnecting the central heating. Could you connect the central heating to a radiator closer or does it have to reroute all the way back to the original location of the boiler?

 

[hazetimesfive]

Floor standing Worcester? Why does it need mains water?

 

[spacey3]

Won't fit in the space - I presumed it required a source of mains water.

 

[swbjackson]

I wouldn't pressurise a system with pipes in the concrete floor. I've seen too many that have failed when they are pressurised.

 

[spacey3]

I am aware that an issue may or may not arise.

However, under the circumstances they are willing to take that chance - my main question still remains the same regarding the movement of the boiler.

 

[swbjackson]

You're best off asking your installer as it depends on the existing pipe configuration.

 

[spacey3]

Ok installer came had a good look said pressure was fine for an mains pressure system configuration including the rad in the hall being the start.

While I will get a few quotes from a Bosch installer and a Viesmann installer - I was looking at the Bosch because of cost of the unit, however I have been given a good price on the Viessmann 200 30K at £750+vat which is only a few pounds more than the Bosch.

What are the mains benefits of one over the other? Greenstar 30CDi System with Weather Comp or the Viessmann 200 30Khw with Weather Comp.

The cylinder I was looking at was a Gledhill one.

 

[ALEC1]

both bosch and viessmann with their own weather compensation controls are good to excellent boilers....as you have to have an outdoor sensor in Germany you will find the technology very refined... once you have made the effort to understand what the system is trying to do!

In my opinion viessmann are the better of the two...more space in the boiler for working on...and a stainless steel heat exchanger.. Bosch always look over engineered with little space and of course the aluminium heat exchanger ..


go for ********!

 

[spacey3]

Typical the guy quoted for the wrong one it was the 100 he priced up not the 200, not happy. Anyway will see what I can get the 200 for and compare, you are looking at around £350 difference between the Bosch and Viessmann at the moment

 

[ALEC1]

its an investment for your comfort...to get it right is priceless

a big hint is to size the boiler correctly...do a heat loss calculation...

there is no benefit in oversizing boilers...