Thermostat\controller problem?

[olneys]

Hello

Wondering whether someone would be able to give me some advice?

When my potterton EP2002 controller is in the 'OFF' position, I am able to turn my thermostat up and it results in my boiler coming on.
I have a gravity-fed system, and the controller appears to be working fine with regard to it being set on the timer or when switched in the 'ON' position.

Any ideas on this would be great.

olneys

 

[olneys]

Sorry chaps

Some background information on this may aid your responses -

During the summer time, the EP2002 controller was moved from the kitchen to another room in the house, after testing the system, everything appeared fine. But at that time it was known if problem existed since the thermostat was not turned up when the controller was on in the 'OFF' position. Therefore, the problem may be the wiring.

Recently, the room thermostat was replaced by my father. Unfortunately, it was wired incorrectly and when the controller was switched on to the 'ON' position, this caused the fuse in the power flex outlet to to the boiler to blow.
This thermostat was a different model to the one is was replacing, so I decided to replace it with an exact model and this appeared to result in the system working correctly.
But only by accident now, I have found that the boiler fires up when the thermostat is turned up and the controller is in the 'OFF' position.
Therefore, could this incorrect re-wire have caused a component in the controller to 'pop' and hence be causing the problem.

time and efforts appreciated.