My boiler (Valiant Ecotec Plus 630) fires up at night despite the timer being off. The boiler only heats for around 30 seconds, then displays S07 (pump overrun) for 5 minutes before shutting down. 45mins or so later it’ll fire up again and the process repeats. This only happens during cold weather.
Although the boiler is within an inside cupboard, my hot water pipes run through an unheated garage and I am 99% sure a pipe stat (Honeywell L641B1004) attached to these pipes is responsible for the call for heat. The pipe stat is set to 5c. There’s no frost stat, only the pipe stat, although the boiler does have built in frost protection.
The boiler firing up annoys me as I can hear it from my bedroom, especially the vibration of the pump running for 5 minutes just as I’m drifting off to sleep!
I’m guessing that what’s happening is the pipe stat calls for heat, the boiler heats and circulates water, the hot (/warm) water quickly reaches the pipe stat and as the stat is set to 5c it equally quickly terminates the call for heat. The pump then runs for 5 minutes as per the default setting for my boiler. Does that sound right?
Any thoughts on what can be done to stop the boiler from firing up in this way, or is this just normal operation that we need to get used to?
Although the boiler is within an inside cupboard, my hot water pipes run through an unheated garage and I am 99% sure a pipe stat (Honeywell L641B1004) attached to these pipes is responsible for the call for heat. The pipe stat is set to 5c. There’s no frost stat, only the pipe stat, although the boiler does have built in frost protection.
The boiler firing up annoys me as I can hear it from my bedroom, especially the vibration of the pump running for 5 minutes just as I’m drifting off to sleep!
I’m guessing that what’s happening is the pipe stat calls for heat, the boiler heats and circulates water, the hot (/warm) water quickly reaches the pipe stat and as the stat is set to 5c it equally quickly terminates the call for heat. The pump then runs for 5 minutes as per the default setting for my boiler. Does that sound right?
Any thoughts on what can be done to stop the boiler from firing up in this way, or is this just normal operation that we need to get used to?
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