hxi over-run pump cut off temperature.

[tonyengineer2229]

can this be agisted on the user interface board, i have already replaced the return thermistor. but it still cuts off at 76c which i think is too high

 

[Deleted member 105431]

can this be agisted on the user interface board, i have already replaced the return thermistor. but it still cuts off at 76c which i think is too high

It is timed pump overrun on these.

 

[tonyengineer2229]

can this be agisted on the user interface board, i have already replaced the return thermistor. but it still cuts off at 76c which i think is too high

It is timed pump overrun on these.

hello
thank you for your answer. can the overrun pump time be increased and how.

tony

 

[mickyg]

why would you want to do that? Why don't you tell us what the problem is and what your trying to achieve.

 

[Deleted member 105431]

can this be agisted on the user interface board, i have already replaced the return thermistor. but it still cuts off at 76c which i think is too high

It is timed pump overrun on these.

hello
thank you for your answer. can the overrun pump time be increased and how.

tony

No it can't and it's unnessecary. Is your bypass circuit big enough and correctly balanced/adjusted? That is more important.

 

[tonyengineer2229]

can this be agisted on the user interface board, i have already replaced the return thermistor. but it still cuts off at 76c which i think is too high

It is timed pump overrun on these.

hello
thank you for your answer. can the overrun pump time be increased and how.

tony

No it can't and it's unnessecary. Is your bypass circuit big enough and correctly balanced/adjusted? That is more important.

hello
yes the bypass circuit is big enough, correctly balanced and retested. you say the pump is timed, but to what, it runs for between 4 and 9 minutes, giving a temperature of any where between 76c and 73c. the system has been cleaned and refiled, but 30 to 45 minutes after shutdown there is a discharge of vapour from the boiler. i recollect the pump running on longer than 9 minutes with a much lower temperature. the boiler has been in use for four years with no other faults.

 

[Deleted member 105431]

A discharge of vapour (steam?) from the boiler? Where from?

 

[tonyengineer2229]

A discharge of vapour (steam?) fr
om the boiler? Where from?

round the by-pass,and up the vent, where else. the boiler tubes must still be dirty,another clean-out. i live in a very hard water area and have in the past refilled with softened water, is this a good or a bad thing

 

[Deleted member 105431]

since when has the open vent been the boiler?

Have you range rated the boiler correctly and is the feed and vent configuration correct?

 

[gas4you]

Softened water is bad for your radiators. Ok for boilers as long as they are not Aluminium HE.

 

[tonyengineer2229]

Softened water is bad for your radiators. Ok for boilers as long as they are not Aluminium HE.

hello Dave
thanks for your help

tony