Hi,
First post so apologies if I miss anything out!
I moved into a house around 5 years ago (UK) with a standard gravity fed Central heating System connected to a Sunier Duval Xeon 50ff boiler. In the airing cupboard there are two zone valves and a Pump and in the loft two expansion tanks one for the hot water tank and one for the C/H.
When I moved into the house all radiators were replaced and a lot of thick black sludge came out however since that time the system has been drained and inhibitor added, the last time I did it about 3 years ago the water was perfectly clear.
For awhile I've had a problem with the boiler kettling i.e. lots of gurgling coming from the boiler and pipes. After a few minutes the boiler will switch off then continue this cycle until the tank and room thermostats reach their set temps. All four pipes connected to the top of the boiler are extremely hot as are the radiators and pump. (Too hot to touch without getting burnt).
Things I have checked :
Not knowing much about boilers or central heating systems but having done quite a lot of reading on these forums, my suspicion is that either the boiler thermostat is faulty or there is a problems somewhere else in the system.
Is it possible that the boiler isn't getting a cold water feed or if the pump is too clogged with sludge would this cause the water in the system to get too hot due to lack of circulation?
Alternately if the boiler heat exchanger is clogged up would this cause it to overheat the water as much as it is doing?
Any suggestions / advice would be appreciated before I call out a plumber.
Thanks
First post so apologies if I miss anything out!
I moved into a house around 5 years ago (UK) with a standard gravity fed Central heating System connected to a Sunier Duval Xeon 50ff boiler. In the airing cupboard there are two zone valves and a Pump and in the loft two expansion tanks one for the hot water tank and one for the C/H.
When I moved into the house all radiators were replaced and a lot of thick black sludge came out however since that time the system has been drained and inhibitor added, the last time I did it about 3 years ago the water was perfectly clear.
For awhile I've had a problem with the boiler kettling i.e. lots of gurgling coming from the boiler and pipes. After a few minutes the boiler will switch off then continue this cycle until the tank and room thermostats reach their set temps. All four pipes connected to the top of the boiler are extremely hot as are the radiators and pump. (Too hot to touch without getting burnt).
Things I have checked :
- Zone valves - They appear to be working as when the system is powered off if I move the leavers to "open" they move back to auto with a motorised sound.
- Pump - Spins freely when powered off using the screw in the middle and not running dry as water comes out. If I put my ear to it, it does sound "gritty" when powered on but I can feel it vibrating so it appears to be working. I would mention however that it does seem quieter overall than when I first moved in even on the highest setting of 3.
- Boiler thermostat is set to half way I also moved it as close to minimum as possible. All four pipes coming in and out of the boiler are very hot i.e. close to boiling all of the time.
Not knowing much about boilers or central heating systems but having done quite a lot of reading on these forums, my suspicion is that either the boiler thermostat is faulty or there is a problems somewhere else in the system.
Is it possible that the boiler isn't getting a cold water feed or if the pump is too clogged with sludge would this cause the water in the system to get too hot due to lack of circulation?
Alternately if the boiler heat exchanger is clogged up would this cause it to overheat the water as much as it is doing?
Any suggestions / advice would be appreciated before I call out a plumber.
Thanks
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