Hope someone can help me!
I've got the above boiler, which has recently developed a problem. I know it has the most useless PCBs in the world (in the 10 years I've had it, I've replaced 4), but I don't know what might be causing this problem.
When calling for DHW, the hot water is very hot. This is regardless of the temperature I set using the Hot Water Temp dial on the boiler itself, no matter what I set that to, the water is still boiling. Yesterday, the water was so hot getting to the kitchen mixer that I couldn't touch the tap!
I've had a look through the faultfinding diagram in the manual, and the only thing I could find similar suggested disconnecting the Modulator Solenoid GV3. I tried this and the water came out luke warm, so it made a difference. The next thing it suggested is to check resistance of of hot water temperature sensor, which I can't do as I don't have the means. The two possible outcomes then are replace the Hot Water Temperature Sensor, or replace the PCB (again!).
I can get a PCB from http://www.cetltd.com/default.asp?part=151 and fit it myself, but I'd need to get a Corgi guy in to replace the sensor.
Any suggestions over which of these its likely to be?
Incidentally, it also makes a loud rattly/vibrating type noise when it first starts up (for both DHW and CH), kind of like the case is rattling. The engineer who looked at it before couldn't find what was wrong. I've also recently noticed a groan coming from the pipes when it first fires up for DHW.
Thanks
Dave
I've got the above boiler, which has recently developed a problem. I know it has the most useless PCBs in the world (in the 10 years I've had it, I've replaced 4), but I don't know what might be causing this problem.
When calling for DHW, the hot water is very hot. This is regardless of the temperature I set using the Hot Water Temp dial on the boiler itself, no matter what I set that to, the water is still boiling. Yesterday, the water was so hot getting to the kitchen mixer that I couldn't touch the tap!
I've had a look through the faultfinding diagram in the manual, and the only thing I could find similar suggested disconnecting the Modulator Solenoid GV3. I tried this and the water came out luke warm, so it made a difference. The next thing it suggested is to check resistance of of hot water temperature sensor, which I can't do as I don't have the means. The two possible outcomes then are replace the Hot Water Temperature Sensor, or replace the PCB (again!).
I can get a PCB from http://www.cetltd.com/default.asp?part=151 and fit it myself, but I'd need to get a Corgi guy in to replace the sensor.
Any suggestions over which of these its likely to be?
Incidentally, it also makes a loud rattly/vibrating type noise when it first starts up (for both DHW and CH), kind of like the case is rattling. The engineer who looked at it before couldn't find what was wrong. I've also recently noticed a groan coming from the pipes when it first fires up for DHW.
Thanks
Dave