In article ,
John Rumm wrote:
On 16/04/2018 20:34, Dave Liquorice wrote:
On Mon, 16 Apr 2018 16:57:31 +0100, John Rumm wrote:

Danesmoor 15/19 runs for about 7 mins then locks out, restarts OK
but
every time locks out again, running for less and less time between

lockouts.

A pump failure or blockage would cause it to trip on its internal
overtemp stat.

Presumably this is an oil boiler. Overtemp != lockout. Lockout is
caused by flame failure for more than 10 seconds or so. I'd start by
checking that any filters aren't clogged.

There might also be an optical flame sensor - if that is sooted up it
could cause it sense flame failure.

On my Viessmann, the ionisation sensor was the problem. And they didn't
mention the replacment which has worked perfectly - was a different design.

--
*Do infants enjoy infancy as much as adults enjoy adultery?

Dave Plowman London SW
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