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Both modes are switched offAre Comfort and Auto modes on?
Comfort is the HW preheat function and Auto modulates CH flow temp.
Try turning auto mode ON, it seems to activate some sort of intelligent modulation system.Both modes are switched off
Tried both suggestions with no luckTry turning auto mode ON, it seems to activate some sort of intelligent modulation system.
A faulty zone valve (if S plan) end switch would still be on my list, with CH switched off locate the orange wire from any one of the zone valves and get a mutimeter set to 500V AC and probes between the orange and any neutral or earth and if you get 230V then one of the zone valves is the culprit, if no multimeter a phase tester on the orange will give indication.Tried both suggestions with no luck
Reply to the thread, titled "Is my Boiler short cycling?" which is posted in Boiler Advice Forum on Plumbers Forums.
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