Boiler will not start using remote programmer

[Sumofm]

Hi,
I have a Set3e programmer controlling a Glow Worm boiler with a single room thermostat.
Over the past few days while in run mode boiler has stopped working ans then comes back on at odd intervals.
I have had a boiler engineer out yesterday who tested the boiler to and confrimed no issues with the boiler because there is an oprion to remove the programmer from the circuit and the boiler runs constantly with no issues.
I have today replaced the room thermostat but still the boiler will not start in normal operation mode so all is now pointing to the programmer.
Are these prone to failing ?
The systen has been in for three and half years.
There are no visual problems with the programmer as all lights, times switches etc appear to be working ok.
Before I purchase a new programmer, is there anything else I can try or in your opinion is it likely yo be the programmer.
Thanks.

 

[45yearsagasman]

What boiler? and what other controls are fitted to the system,ie motorised valves etc.What sort of a boiler engineer was he that he didn't identify the fault? I hope no money changed hands.My 1st guess and I don't usually guess is to check motorised valves.Thats all I can offer with so little info.Come back.

 

[Sumofm]

Thanks for the quick response.
The boiler is a Glowworm SX18i and yes there is a motorised valve fitted to the cetnreal heating and one on the hot water.
I have this morning manualy locked open the heating valve to ensure warmth.
Would a faulty valve stop the request getting to the biloer for it to ignite ?

 

[45yearsagasman]

Yes it certainly would.I suggest calling in a decent heating engineer to check the operation of both valves.Suspect synchron motor or microswitch in either valve.If the hot water is no problem then start with the c/h valve,check for movement/noises from the motors and you can usually hear the microswitch making.

 

[Sumofm]

Ok, so when the room stat is low the switch / valve will close. By moving the leave to the open position there is some resistance there which will pull it back. When you then turn the stat up, the switch does not move to the open position.
I have also removed the bypass link on the boiler and with the valve manually locked open, and the control programmer set to constant for both Heating and Water, the boiler will still not start up.
When the boiler is on permantely there is pleant of hot water so guess that value is working ok so do not understand why the boiler will not start on this trigger only under normal operating conditions.

I think I am now confusing my self so if the thoughts, advice are still to the valve then I will call another plumer.

Thanks

 

[matt1e]

Ok, so when the room stat is low the switch / valve will close. By moving the leave to the open position there is some resistance there which will pull it back. When you then turn the stat up, the switch does not move to the open position.

thats normal but if you move the lever manually,the resistance should be gone(persuming the valve has opened of course)

I have also removed the bypass link on the boiler and with the valve manually locked open, and the control programmer set to constant for both Heating and Water, the boiler will still not start up.

again,that's normal too as opening the valve manually doesn't normally close the microswitch on most valve actuators

When the boiler is on permantely there is pleant of hot water so guess that value is working ok so do not understand why the boiler will not start on this trigger only under normal operating conditions.

I'm guessing that the hot water's up to temp so the boiler is only firing occasionally to keep it topped up

I think I am now confusing my self so if the thoughts, advice are still to the valve then I will call another plumer.

Thanks

your problem will be with the
valve
the programmer
the room stat
or the wiring
do you have a multimeter?
if not then turn on the CH, turn up the room stat go to the valve and move the lever manually........is the resistance still there? if not then the programmer and room stat are ok so we can rule them out if it is still there then you will need something to test with

Matt

 

[Sumofm]

Thanks Matt

Yes I have a multimeter, what and how should I test ?

Thx