worcester 28i junior not firing

[manic26]

Got called to service above boiler only to find red light flashing with fault. Asked for MI, none in there. Reset it nothing both in CH and DHW. Looked at pressure gauge less then 1 bar so topped it up to 1.5 and reset nothing. Fan going on fine whenever there is a call for heat and the ignition sparks a few times then nothing. Opened up and put manometer in inlet there's gas pressure there. Done same at the outlet side with the call for heat and reset button depressed, no pressure. An hour later no joy.

Anyone had similar experience with this boiler and anyone with any suggestion please

 

[Dotty]

Moving to the GSR forum.

Please watch where you post.

 

[manic26]

Apologies Croppie just didn't seem to find that button 🙂

 

[Millsy 82]

Try the OH stat or low pressure sensor. More than likely the low pressure sensor blocked up. Top right hand of the boiler both are together link the one out see if it fires if it doesnt link other out and test then clean out/ replace

 

[bewsh]

You won't get any pressure on the "outlet" of the gas valve mind as it's a zero-governor.

What's the blue light doing? Depending on how that flashes as well will mean different things.

 

[manic26]

No sign of blue light at all

 

[vern]

You won't get any pressure on the "outlet" of the gas valve mind as it's a zero-governor.

What's the blue light doing? Depending on how that flashes as well will mean different things.

SE junior not greenstar pal

 

[vern]

Try the OH stat or low pressure sensor. More than likely the low pressure sensor blocked up. Top right hand of the boiler both are together link the one out see if it fires if it doesnt link other out and test then clean out/ replace

^^^^^^This low pressure cut off blocked with black gold, drain, unscrew, carefully poke wire into sensor without puncturing diaphragm, then unblock hole into main heat hex....ptfe sensor, screw back in and refill

 

[bewsh]

Ah, my bad! That'll teach me for not reading properly! Ignore my last comment 🙂

 

[manic26]

^^^^^^This low pressure cut off blocked with black gold, drain, unscrew, carefully poke wire into sensor without puncturing diaphragm, then unblock hole into main heat hex....ptfe sensor, screw back in and refill

I have not been back there since but before leaving I also probed with a voltmeter on the gas valve assembly and found about 2 volts in the blue wire but none in either purple or brown wires. Can anyone confirm it was correct

 

[manic26]

Try the OH stat or low pressure sensor. More than likely the low pressure sensor blocked up. Top right hand of the boiler both are together link the one out see if it fires if it doesnt link other out and test then clean out/ replace

Linked out the outside sensor and boom the ignition on and the indicator goes red

 

[Millsy 82]

The low pressure sensor then? Probably gunked up take out carefully clean out and check the heat ex where it connects to for a blockage put it back together. 9 times out of 10 that will do the trick.

 

[manic26]

The low pressure sensor then? Probably gunked up take out carefully clean out and check the heat ex where it connects to for a blockage put it back together. 9 times out of 10 that will do the trick.

Should have taken the picture, looked like the end of a spark plug.

 

[manic26]

No glee at all

 

[manic26]

No glee at all

Sorry not glee but hole ;p