Danesmoor 15/19 run problems

[narvik1965]

Hi - have an older model (mid 90's?) Danesmoor 15/19 floor standing boiler regularly serviced (Boilerman has emigrated!) which is powering off after a couple of hours in the evening and then powers up automatically the next day. I found someone on this forum which seemed to be the identical problem some years ago and the solution was to change the automatic high limit stat which I did but the same problem persists. There is a manual stat - just wondering if I should replace that? Does anybody have any ideas what it might be - there are no lockout problems - boiler is working perfectly apart from switching off 2 hours into set programme. Any ideas gratefully received.
Thanks, Mark

 

[oilboffin]

First off I'd get a sparky to check it all out.Bob

 

[oilhead]

Assuming the programmer is working OK, the problem must be with the boiler thermostat(s). Does the pump keep running? How long are you waiting before deciding the boiler is not going to start up?
If the boiler gets up to temperature, and the system is not using the heat, the boiler will stay off until it cools.

 

[narvik1965]

Hi - thanks for getting back - the programmer seems to be working fine - pump runs even when the boiler itself has powered off. When the boiler switches off I don't do anything - it just starts as normal next morning. I run it for 90 mins in the morning (6:30 - 9am) and it runs to the end of the programme but in the evening I run it from 5 to 9:30 and powers off around 7:30 to 8pm and doesn't come back on until 6:30 am next morning. I have tried to get it running but doesn't not respond - seems to need to cool down or reset before it can start up again - don't know how long that takes but I did try the other evening around 11pm and it wouldn't fire up.

 

[oilhead]

You need a good diagnostic electrician/boiler technician. Without knowing the full model, if you have a post purge unit fitted, this could be faulty, or it could just be a simple boiler thermostat.