I have the same tripping out problem as many on this board, however I have tested the voltage between the Neutral and SWL terminals in the boiler and get no voltage when the room thermo and programmer should be asking for heat.
If I bypass the controllers in the system and put a wire from the Live terminal to the SWL terminal in the boiler the boiler fires up OK. I then removed this wire to carry out the test below.
If I remove the programmer and place a wire between the Live terminal and the CH ON terminal and the room thermo is set at its highest setting (30), I get no voltage measured at the SWL terminal at the boiler.
The strange thing with the wiring in the room thermo is that when the room temp' is below the setting of the thermostat (ie calling for heat) the switched wire has no voltage but one of the other terminals in the room thermo which has no wire connected to it has a 240 v output. It has worked fine like this for 4 years. No one has rewired the room thermostat.
If it was the PCB as indicated on this board then surely I would not be able to get the boiler to fire up when I shorted the N and SWL terminals.
Or perhaps my understanding of how these things work is not as good as I thought!!
Any help would be gratefully accepted.
If I bypass the controllers in the system and put a wire from the Live terminal to the SWL terminal in the boiler the boiler fires up OK. I then removed this wire to carry out the test below.
If I remove the programmer and place a wire between the Live terminal and the CH ON terminal and the room thermo is set at its highest setting (30), I get no voltage measured at the SWL terminal at the boiler.
The strange thing with the wiring in the room thermo is that when the room temp' is below the setting of the thermostat (ie calling for heat) the switched wire has no voltage but one of the other terminals in the room thermo which has no wire connected to it has a 240 v output. It has worked fine like this for 4 years. No one has rewired the room thermostat.
If it was the PCB as indicated on this board then surely I would not be able to get the boiler to fire up when I shorted the N and SWL terminals.
Or perhaps my understanding of how these things work is not as good as I thought!!
Any help would be gratefully accepted.