In article ,
F news@nowhere wrote:
On 20/09/2013 14:19 Muddymike wrote:

Anyone got any experience and opinion on Viessmann boilers with or
without weather compensation?


No personal experience but I see they are rated third best after
Worcester and Vaillant in the latest Which report.

That's interesting.

I wonder what Which do to take aging into account? The plumbers I've
been talking to have said that the WB is/was an excellent boiler and
they have fitted them for years but, now the boilers are aging and they
are servicing them regularly, they are starting to notice the aluminium
depoits from the interior of the heat exchanger and are needing to
replace the exchangers. The heat exchanger on ours has a rippled
exterior and you can hear it kettling.

WB, apparently, deny there's a problem.


I'd be surprised if Which had enough data on early Viessmann boilers to
come to an accurate conclusion about life.

They claim the reports are based on sample size;

84% Worcester 1,911
83% Vaillant 903
80% Viessmann 103
76% Remeha 39
69% Glow Worm 446
This is the Top 5 by % satisfaction

Mike