CH Issue - Potterton Pro Max HE Plus

[Dean Towey]

Hi all,

Would really appreciate if someone could give me some advice.


I have an issue where if my heating is set to off on the programmer and I turn the Thermostat up the heating will come on.


Which pretty much means I either have to have the heating on or off - which is bit of a nightmare during the night when you want the heating to come on in the morning.


I had a friend look at it, and we replaced both the PCB in the boiler and purchased a new Programmer yet still have the issue.


Any able to think of something that could be causing this issue?


Thanks in advance

 

[Chuck]

I had a friend look at it, and we replaced both the PCB in the boiler and purchased a new Programmer yet still have the issue.

So, now you have two problems. Your original one and a boiler that's been tampered with by, I assume, people who are not registered as Gas Safe competent persons.

You need to get a Gas Safe qualified person in. They should be able to fix the problem without difficulty as long as the boiler hasn't been damaged by your ill-advised attempted repair.

 

[Dean Towey]

Hi thanks for your reply, he does actually work in the industry and is Gas safe qualified engineer. He tested the boiler and couldn't find any issues apart from the PCB needing replacing and we just replaced the programmer in case it was something to do with that as the previous one was old.

He thinks it could be a wiring issue but thought I'd seek a second opinion.

 

[Chuck]

He thinks it could be a wiring issue but thought I'd seek a second opinion.

The symptoms you describe resemble those of a system when the programmer and thermostat have been misconnected in parallel rather than in series. If the system has always behaved in this manner (unlikely) it's probably just an installation mistake that any competent electrician can rectify.

If its a symptom that has only appeared recently, it could be an issue external or internal to the boiler. An electrician who is experienced with central heating wiring will be able to tell you which within a matter of minutes by measuring the voltages at the boiler and programmer/thermostat.