help , i have a isar he30 combi boiler the problem i am having is heating is turned off via honeywell cm927 thermostat but the heating remains on . has any one got any ideas why this is happening as i have turned the system off
ideal isar HE30
GCN 47-348-30
CH stays ON
2 possible causes
does C* appear on boiler display when CM927 turned off?
[with green LED lit & sometimes flashing red LED]
if YES
then faulty timer receiver unit sending switch live to boiler mains connector
if NO
does "d" appear regularly [when DHW not used]
most likely divertor valve seized
manwithnoname
May 2012
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