On Fri, 11 Mar 2011 14:33:20 -0800, Mathew Newton wrote:

If you are going to draw comparisons you need to be thorough on both
sides. You have omitted the potential issues you may face with the
secondary heat exchanger and diverter valve that the combi introduces.
Also, the lack of any backup hot water availability should the boiler
breakdown.
....
Besides which, you really ought to be comparing against a modern
unvented cylinder as these address most of your concerns about
'conventional' systems - heat loss, flow rate, pressure, float valves
etc.

Unvented cylinders introduce their own complexity - pressure and
temperature relief valves, pressure-reducing valves, expansion vessels or
bubbles, safety override zone valves ...

Unfortunately when some of these items fail they can, in extreme cases,
reduce the safety of the unvented cylinder. Like nuclear power plants
these are normally quite safe ...


--
John Stumbles

Religion is like a penis. It is fine to have one. It's ok to be proud of
it.
Just don't wave it around in public or try to jam it down my child's
throat.






--
John Stumbles

militant pacifist