glow worm compact 100e

[stevetheplumber]

got a glow worm compact 100e which lights on full flame for a second and then shuts down to low imediately this occurs on both hot and heating demand so im thinking either board or gas valve what i need to know realy is what voltages i should get at gas valve ive got 4 wires on valve red blue black and white unfortuanatly its at a friends house and when i was there i had no tools so nothing tried yet sods law it 30miles away but owe this guy a favour

 

[diamondgas]

According to mi's - 24-50v AC black and white ... 130v AC red and blue ........ I'd asume the modulating coil will be the black and white yeh?

 

[stevetheplumber]

little update my mate whose a sparks has measured 25v across black and white but only 72v across blue and red so im thinking board now anyone confirm this ?

 

[kingdomfrank]

I had one last week with the same problem but only in hot water, bottom middle of the pcb had burn marks, changed it and all was fine.

 

[Billy Bob Bob]

what resistance are you getting on the primary thermister when cold?

 

[stevetheplumber]

dont think it has a primary thermistor one for heating one for hot water to my way of thinking unless there both gone niether should have the same effect on both functions

 

[Billy Bob Bob]

http://www.glow-worm.co.uk/stepone/data/downloads_sd/50/00/00/compact100e.pdf
here you go steve,check that your primary ntc has a resistance of 10 k when cold if its different to this its knackerd ,note that test voltages are given at the end of the mi,s hope this helps

 

[Billy Bob Bob]

dont think it has a primary thermistor one for heating one for hot water to my way of thinking unless there both gone niether should have the same effect on both functions

primary> heating ntc most combis look at this first before going to full rate

 

[diamondgas]

:iagree: got to check the resistance of the ntc steve. If the boilers imediatly modulating to minimum gas rate something is telling it to do so yeh? 🙂