I have checked the FAQ and scoured the forum.. hope you can help ?
Everything listed above works fine - 95% of the time. The system is well maintained, full of all the right inhobitors etc etc... EXCEPT, the upstairs heating doesn't work on it's own.
1) HW is fine
2) Downstairs heating is fine
3) The upstairs heating will work but only if the downstairs heating is also on (i.e. the neon on the 'stat is glowing).
I only discovered this recently when I commanded the upstairs zone to come on earlier than downstairs, and noticed that despite the thermostat being powered, and engaged, the rads were
When the downstairs stat clicks on, and the timer is correctly sequenced, then the boiler fires up and both up and downstairs get hot.
Notes:-
When I stuck my head in airing cupboard and ask someone to operate the upstairs stat, the diverter valve moves as it should
I have a new V9 control box fitted some 3 years ago to cure a totally unrelated problem.
The system is 5 years old
Everything else...works perfectly.
THANKS !
Everything listed above works fine - 95% of the time. The system is well maintained, full of all the right inhobitors etc etc... EXCEPT, the upstairs heating doesn't work on it's own.
1) HW is fine
2) Downstairs heating is fine
3) The upstairs heating will work but only if the downstairs heating is also on (i.e. the neon on the 'stat is glowing).
I only discovered this recently when I commanded the upstairs zone to come on earlier than downstairs, and noticed that despite the thermostat being powered, and engaged, the rads were
When the downstairs stat clicks on, and the timer is correctly sequenced, then the boiler fires up and both up and downstairs get hot.
Notes:-
When I stuck my head in airing cupboard and ask someone to operate the upstairs stat, the diverter valve moves as it should
I have a new V9 control box fitted some 3 years ago to cure a totally unrelated problem.
The system is 5 years old
Everything else...works perfectly.
THANKS !