Would welcome help with boiler fault

[poriet]

HI,
I have a 30 yr-old Ideal E Type RS (35N ) Balanced-flue boiler.
The main burner is not lighting. There is power down to the gas-valve
( this goes to a solenoid, I believe, although it would be a 240V solenoid, whereas I have heard tell of 24V ones? )
The gas-valve 'knob' is grey. ( I dont know the exact gas-valve model, but it has V404 stamped on it ) I have performed the 'turn-on' procedure many times. In the past, it has always worked OK, but now it wont. BTW, the pilot-light IS lit.

I have checked the solenoid for continuity and the coil resistance is 5K. Rated as 240V@20mA, I would expect 12K. Also, I dont hear a 'clunk' from the solenoid when it energises, although maybe that's normal.

Is this a replacement job? Just how complex is it to fit a new valve?
I know you're expected to be competent, but it cant be that tricky to
undo 2 nuts. Does a new valve need 'setting up' or is it a plug-in replacement? ( just asking: it's a nightmare to try and find an honest trader )

Regards
Bruce

 

[twgas]

It does need a RGI to replace gas valve (if indeed that is the problem) and set it up, they are most certainly not plug and play!!!!!!!

 

[DP]

Why 12k and not 5k?

 

[poriet]

Thanks for the replies
I probably need an RGI, but I'm dead reluctant to ask BG because their prices are OTT
I see you have a search engine for local traders! I'll try that
As for the solenoid resistance, unless I'm making a horrid algebraic error,
if V=240 and I=20mA, then R = 12K doesnt it?

bruce

 

[Agile]

Well it would if it was purely resistive.

But when you take physics GCSE you probably learn about inductive loads!

You badly need an RGI !

We dont give advice on or encourage illegal gas work!

Tony

 

[poriet]

Tony,
If the resistance R is 5k ( measured by the meter) and the required impedance is 12K, then if Z(coil) and R are 90deg out of phase, the coil impedance needs to be 11K and the inductance at 50Hz is 40H. I havent measured it, but it sounds a lot. I forgot that mains relays must have an AC component.
I still need a new gas valve!

Bruce

 

[Dan Robinson]

And an rgi to fit it.

 

[matt1e]

Well it would if it was purely resistive.

But when you take physics GCSE you probably learn about inductive loads!

You badly need an RGI !

We dont give advice on or encourage illegal gas work!

Tony

And after reading through, I have to say that in this thread, I totally agree with tony

 

[bernardgreen]

I probably need an RGI, but I'm dead reluctant to ask BG because their prices are OTT

Not probable you DEFINATELY need an RGI

BG prices may appear to you as being OTT but then you ( or your relatives ) may consider funeral director's prices to the OTT as well

 

[Agile]

But that was TWO years ago !

By now they will be even higher!

Tony