In article ,
"John" writes:

"Ed Sirett" wrote in message
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On Thu, 30 Dec 2004 15:00:14 +0000, Andrew Gabriel wrote:


Cheers. Some things I have gleened -- may not all be true...

Several people here have noted the temperature control is not
adiquate for ideal heating and hot water in a condensing system.
Another thing the Keston is missing is provision for connecting
remote frost stats.

??
Either direct from the mains to the demand terminal in which case the
boiler will heat the bypass circuit, or direct from the mains to the
CH zone valve if the whole house needs protecting.

Via or in series with a Danfoss AT/F pipe stat set to about 15/20 degrees
which will only keep the pipes just warm then shut off

Or have I failed to understand what you want to do?

Well, ideally have the pump running continuously when some pipework
is in sub-zero areas, and have the boiler firing up occasionally as
necessary to maintain the pipework temperature above freezing.
A similar mod to fred's which instead forced temperature to lowest
setting would do this. It was just rather annoying that the Keston
already has that logic internally, but no ability to trigger it
from a remotely positioned frost stat. John's solution would work
in a similar way but without the continuous circulation, which for
lagged pipes is probably good enough most times.

--
Andrew Gabriel