hi can someone enlighting me , ravenheat csi 85 b(t). no central heating hot water ok. when i pull one wire from central heating sensor and reconnect ch fires for 30 secs. or so if i pull the stat offv the pipe ch stays on. so i have changed sensor but still got same prob. phoned tech and they suggested plate to plate? or main exchanger blocked, which i do not believe is the problem. any ideas im thinking circut board.thanks for any help.
plumbing an heating
- Thread starter lee32
- Start date
monkey stuck in the flue 
what temp is the flow when it cuts out
what temp is the flow when it cuts out
hi kev, the hotwater works okay so think the flue is okay , i dont know the temp of flow, the boiler fires for 30 seconds or so,when the sensor is clamped to the pipe , with the sensor pulled from its seat, the boiler stays lit and rads work okay it modulates the flame . but when the clamp is clipped onto the pipe below the combustion chamber the boiler cuts out.?
Diverter stuck......
Iso valve closed.....
Pump part blocked......
Or the more common cause, a monkey stuck in the flue
Iso valve closed.....
Pump part blocked......
Or the more common cause, a monkey stuck in the flue
how can it modulate if the sensor is not sensing anything other than fresh air.
I must admit I'm not terribly conversant with this boiler but surely the sensor controls the gas rate (albeit not directly)
no the diverter cant be stuck the heating and hot water works.
the iso's are open.
the rads heat up so pump okay. the c.h. sensor may control the gas valve indirectly but i would have have thought more likely it is the thermistor. i just thought someone may have come up against this problem, i spoke to ravenheat tech and he toold me to check the plate to plate exchanger ,which i cant imagine has anything to do with it . im still suspect of the p.c.b. thanks for your suggestions.
the iso's are open.
the rads heat up so pump okay. the c.h. sensor may control the gas valve indirectly but i would have have thought more likely it is the thermistor. i just thought someone may have come up against this problem, i spoke to ravenheat tech and he toold me to check the plate to plate exchanger ,which i cant imagine has anything to do with it . im still suspect of the p.c.b. thanks for your suggestions.
hi mik
i have changed the sensor , and still got the same problem , i guess i will have to have a closer look at the wiring . thanks.
i have changed the sensor , and still got the same problem , i guess i will have to have a closer look at the wiring . thanks.
i dont think the pipe is really hot im sure i can keep my hand on it. the heat is leaving the boiler okay as i said the rads get hot. so i dont think there is a blockage.
tell me about it , thanks for your time , i will endeavor to get to the root of the problem. so i don't end up lookin the incompetent fool i am. and walkin out without the reddies.
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