Hi, I have one of the R29, boilers fitted on an open system. The
boiler is about 4 to 5 years old and when the first fitted I had
numerous problems with the heat exchanger failing due to overheating
and burning inside black inside.
After the third replacement. I got an electrician to fit a 'pump
overrun in order to keep taking away the water after the boiler had
stopped burning to ensure no overheating
This is worked fine for about three or four years. However now I have the boiler switching on getting up to temperature circa 85° or so and then switching off.
The result is that the hot water is working fine and the radiators upstairs are also warm (not overly hot). However, the radiators downstairs virtually cold. There is only one zone for the whole heating system. The pump certainly is running as I can hear it and feel it vibrate
I have examined every single radiator and there are no air blockages in any of the individual radiators. I also run a tiny amount of water from the bottom of the system and there doesn't seem a blockage here either
I think the heating valve appear to be working ok and so does the hot water so not sure what it can be??
My thoughts were either of the following:
1) An air blockage, however, there is no air in the radiators and the cold water tank is all functioning correctly . So can I rule this out???
2) The pump could be working but not drawing sufficient hot water away from the boiler, thus causing it to overheat & shut down - could this be the case?? Is there anything I can do to check the pump is actually working correctly before I replace it???
3) If I switch the 'H' valves to manual and left open would this rule these out as an issue if the problem persisted??? - One of the 'H' valve electric box tops seems to be hot long after it has been taken from from system (hot pipes) - could this be telling teh system to shut down??
Any other thoughts???
I would appreciate any help given
boiler is about 4 to 5 years old and when the first fitted I had
numerous problems with the heat exchanger failing due to overheating
and burning inside black inside.
After the third replacement. I got an electrician to fit a 'pump
overrun in order to keep taking away the water after the boiler had
stopped burning to ensure no overheating
This is worked fine for about three or four years. However now I have the boiler switching on getting up to temperature circa 85° or so and then switching off.
The result is that the hot water is working fine and the radiators upstairs are also warm (not overly hot). However, the radiators downstairs virtually cold. There is only one zone for the whole heating system. The pump certainly is running as I can hear it and feel it vibrate
I have examined every single radiator and there are no air blockages in any of the individual radiators. I also run a tiny amount of water from the bottom of the system and there doesn't seem a blockage here either
I think the heating valve appear to be working ok and so does the hot water so not sure what it can be??
My thoughts were either of the following:
1) An air blockage, however, there is no air in the radiators and the cold water tank is all functioning correctly . So can I rule this out???
2) The pump could be working but not drawing sufficient hot water away from the boiler, thus causing it to overheat & shut down - could this be the case?? Is there anything I can do to check the pump is actually working correctly before I replace it???
3) If I switch the 'H' valves to manual and left open would this rule these out as an issue if the problem persisted??? - One of the 'H' valve electric box tops seems to be hot long after it has been taken from from system (hot pipes) - could this be telling teh system to shut down??
Any other thoughts???
I would appreciate any help given
