E133 Error Potterton Titanium 24

[abc_plumb]

Hiya fellow gas engineer.
Need some help on this boiler fault.

Went out to this E133 Error on a Potterton Titanium 24 (GC: 47-393-39)

I checked the inlet standing pressure which was at 25mb. Boiler attempts to fire and the pressure drops by 1mb but the gas valve doesn't open. Checked the black gas lead to the gas valve and I was getting
230v between pins (3L) & E
230v between pins (3L) & (4N)
230v between pins (3L) & (1N)

Checked the gas valve coil and resistance was all good.
Checked X3 on the pcb between 1&2 and getting 230v.
I suspected a sticked gas valve so went there today to replace it with a new one and it's the same fault.

I was told that the pcb was replaced for a reconditioned one 5 weeks ago.

I'm leaning towards the pcb but I'm getting the correct voltage at the black plug end that fits into gas valve???

Would appreciate some help on this please.

 

[ShaunCorbs]

Gas should drop to under 5 mbar eg 1 or two with the gas isolated

 

[abc_plumb]

Hi Shaun

Are you saying I should've tested the gas valve but turning the boiler gas isolation off then tried the firing sequence. From 25mb is should've dropped to 1 or 2mb?
Handy tip for next time.

I did remove the 3/4" nut above the gas valve and I know the gas was not getting through the g/valve.
I'm positive the gas is not getting through, just can't understand why?

 

[ShaunCorbs]

Hi Shaun

Are you saying I should've tested the gas valve but turning the boiler gas isolation off then tried the firing sequence. From 25mb is should've dropped to 1 or 2mb?
Handy tip for next time.

I did remove the 3/4" nut above the gas valve and I know the gas was not getting through the g/valve.
I'm positive the gas is not getting through, just can't understand why?

Yes proves if the gas valve is opening

If you have power eg 240v on the pins and no drop gas valve (eg with supply isolated)

 

[abc_plumb]

I'm 100% sure the gas valve is not opening.
I just can't understand why it wouldn't even with the 230v at the leads

 

[ShaunCorbs]

Faulty ?

 

[abc_plumb]

Faulty ?

I've put a brand new gas valve yesterday and I'm getting the same fault. I'm thinking the gas plug is not making the contact with the pins to transfer the 230v to the gas valve.

Feel like my clutching at straws, but can't get my head around this one!

 

[ShaunCorbs]

I've put a brand new gas valve yesterday and I'm getting the same fault. I'm thinking the gas plug is not making the contact with the pins to transfer the 230v to the gas valve.

Feel like my clutching at straws, but can't get my head around this one!

Lift the plug slightly so you can check at the terminals

 

[abc_plumb]

Lifted it, wobbled it, squeezed it..... done it all, but nothing.

 

[ShaunCorbs]

Lifted it, wobbled it, squeezed it..... done it all, but nothing.

I mean you can test with a multi meter on the gas valve pins to see if the connection is ok just a thought as well did you remove the bung on the new gas valve they sometimes put them in to save any rubbish going in them while in the box