Glow Worm 30CXi Diverter Advice

[Whitespirit66]

Wondering if I can get some advice about a GW 30CXi diverter valve on my brother's boiler which I seem to have become responsible for. It's not a paying job, but if anyone says don't think about tackling this as it's not straightforward, I will leave it as the boiler is in the loft. I don't normally get involved with boiler repairs and I'm not familiar with this model. The hw stopped working after putting the ch on for first time and running the hot tap heats the rads. I took the motor off the Diverter valve and the pin in the valve is able to be pushed in by the motor to the ch position, but is jamming and won't return to the hw position. I managed to get some long nosed, right angle pliers on the pin to give it a pull and hw was restored - but the pin is still stiff.

I assume I need a new div. valve cartridge? As it's the pin that's jamming, can I get away with unscrewing the right hand side and removing the pin and fitting a new one? Or do I need to unscrew the bits on the left of the valve too?

Also, are either the right hand side components inc. pin, or even both sides (left and right) replaceable without removing the hydroblock.

Many thanks for any advice about this problem and a solution. I'm keen to repair it without removing any bits that don't need to come out and would prefer not to disturb the hydroblock. I'm aware these things can be leakers!

 

[Whitespirit66]

Looks like you can buy just the right hand side as a repair kit which includes the cartridge screw-in with the pin. If the pin's sticking, will just fitting this solve the problem, or is something else in the diverter causing the pin to jam?

http://www.euroboilerparts.co.uk/rk...valve-repair-kit-2000801903-801903-1323-p.asp

Seems too cheap. Is it genuine G W? Are Euro reliable?

 

[Whitespirit66]

BUMP.

Has anyone out there got any advice at all? Maybe if you don't want to post on open forum, someone could give a few tips in a pm to me. It's not gas related, and doesn't involve working in the room sealed area of boiler.

I'm sure there's a helpful chap or chapess out there.

 

[Dan Robinson]

With the head off you should be able to check the motor driving open and close easily enough.

The cartridge is prone to sticking and symptomatic of other problems to be dealt with.

Euro parts are often cheap, btu they will do the job if you brother doesn't want to spend any money.

 

[Whitespirit66]

Thanks Dan. Yes, motor is fine, it's the d/v pin that's not sliding back out into hw position when ch has been used. If I understand you correctly, the stiff pin is caused by something else rather than just wear and tear? Is it possible to say what may have caused the stiffness?

I was thinking that if it was just the pin then just replacing the right hand side part of d/v with the Euro part would solve it, but sounding like it's not that straightforward. Am I right in thinking that to replace both sides of the d/v properly, the hydroblock would need to come out too? Or can it be done with it in place? Apparently the sides of the casing can be hinged/removed so this may help.

My brother doesn't mind paying out for proper G W parts, but I thought I would do it for him if poss as he's suffering from an overtime drought - start the violins. If it's going to be a mare, will get someone in. I do all the non gas repairs on my Turbomax, but the GW is a bit of a s**t box and I'm wary of it's rep.

Thanks again, Dan. Really appreciated.

 

[St0rmer66]

It can be done with the block in place but access is from the left by taking the case off which requires opening the combustion chamber... not DIY.

 

[Whitespirit66]

It can be done with the block in place but access is from the left by taking the case off which requires opening the combustion chamber... not DIY.

Thanks. In that case, I don't fancy taking the block out so will farm out to my tame gas bod - who's just gone away for 2 weeks.

Last questions. If he replaces both halves of the dv, is it likely to cure the fault? Dan seems to indicate that although the d/v is faulty, it's being caused by something else. If I've got the right end of the stick, what also needs to happen to make sure that the new parts aren't damaged again?

 

[St0rmer66]

Clean the water in the system. Even if it initially "looks" clean there is likely to be a build up in the valve where the waterways are narrow.

 

[Dan Robinson]

Diverter valves tend to get sticky if there is a load of Sludge in the system.

Check the state of the old one and if it is caked in black crud then you have issues.

If it is clean the nit is just a failure of the part.

 

[Whitespirit66]

OK. Will do. The water was last flushed (cleaning fluid, not power flush) and changed about 5 ish years ago. Inhibitor was added and I put a Boiler Buddy on at the same time - which is cleaned out annually. Had to use a Boiler Buddy as the boiler is in loft, low to floor and being a bungalow, all the 22mm f and R pipes are low on loft floor with tee'd drops down to individual rads. So nowhere sensible to get any other sort of filter near the boiler return. The BB was the only choice without repiping/re-routing.

The reason for all the above was because the plate had blocked not long after he bought the bungalow. The boiler was only fitted 18 months before he bought it. The Boiler Buddy does a good job as it collects plenty of flakes and after 5 years, the hw is still red hot on the replacement plate hex. So, the BB seems to keeping it clear.

Thanks to all for your help.

 

[Dan Robinson]

A bit of a error in thinking though WS.

The filter doesn't collect everything first pass, so there is going to be matter collecting elsewhere as well.

 

[Whitespirit66]

No, I wouldn't expect any filter to catch everything, least not a Boiler Buddy. But as the boiler's plate hex clogged in it's first 18 months of use without a filter, but has now had trouble free hw for 5 years with the filter, it must be mopping up a good percentage of the ferrous particles. It's always going to be more of a compromise putting a new, modern boiler on an old, existing system.

Maybe a strainer in the pipework may also help with any non-ferrous debris?

 

[Whitespirit66]

As it's getting colder and my brother has a frail, elderly cat, I'm going to have a go myself so he can have the ch on. Will be 2 weeks before my usual RGI will be back from hols. I'm going to remove the hydroblock, so as not to contravene regs by having to remove the left hand casing panel which would mean exposing the room-sealed compartment. The manual's instructions for removing the block are quite clear.

I have bought the cartridge overhaul kit today, and I have one question. In the bottom of my image, there is a black plastic piece in the kit that doesn't seem to appear in the exploded diagram of the div. valve internals. I'm guessing it's not suppose to be fitted in the block/dv permanently.

What is this part for? It looks like a bung of sorts. Is it used to bung up one of the two cartridge holes when they are removed to aid removal of the d/v internals? Or is it a removal tool to help remove a part of the d/v internals?

I'm intrigued!

DSC00918

• Whitespirit66
• 23 Oct 2015

 

[St0rmer66]

Been a while since I did one but pretty sure you can discard it. That kit fits a few different boilers.. Must be that one of them needs it (never come across a use for it myself).

 

[Whitespirit66]

OK, thanks Stormer. I'll chuck it in the bin.