Leaking combi (Vokera)

[ds]

Hi

My Vokera Maxin 24e, a combi, is leaking water. I first noticed it a few weeks back when it was just a drop or two a minute - now it's so bad i've had to switch it off, and stop the CW supply. The system has lost all pressure too.

The leak is coming from near a solid brass disc-shape looking part, that has six bolts holding it together. Immediately next to this (and feeding into it) is an approx 22mm brass pipe with 4 bolts, spaced equally apart, being screwed in towards the centre of the pipe. Two of these bolts are missing and the leak is coming from one of the missing bolt holes.

The boiler has been in the house when we moved in about 9 mths ago, and hasn't been tampered with during our time.

Pl do forgive the poor description of the components. I have actually managed to install a combi boiler once, but it was relatively easy and i never even had to look at the parts inside!

Any assistance will be much appreciated.

thanks

Daljit

[Paul Barker]

Sounds like the diverter valve. These are a nightmare. I changed one o an Ariston Friday night, 1/2 an hour to change the part 2 hours to fi all consequential leaks, wish I'd never started the job.

Only thing you can do is shut of flow and return, shut off cw. crac the joints where the leaks are, catch the water, if you can get an ring/wahser kit for it fit that, unlikely that you can, so get it al dry and re-assemble with silicone sealer and leave it over night befor refilling.

Good luck.

Some combis are made to leak

-- Paul Barker

[ds]

Thanks for your tip Paul. A diverter valve makes sense - the leaking part is connected to the two boiler outputs - HW and flow.

I've just checked on the web and found a picture of a Potterton diverter valve and i'm positive that this is the part i need (only for a Vokera!). If anyone knows where i might find this, would be appreciated. Will phone round local suppliers tomorrow.

Incidentally, i was mistaken in my original post. The system had lost all pressure, but once i filled it up again, it stayed filled. This discovery means i can actually use the heating for short periods as long as i have a bucket beneath to catch the trickle of water.

Certainly doesn't look an easy part to replace - seems to be connected to half a dozen different pipes!

Daljit

[Aldrich]

Hi Daljit

I am unable to help you with your problem. However, I think I have the same problem with my Vokera boiler. Please let us know how you resolved this.

Best regards

David

[Paul Barker]

If it's just a leak you don't need a new diverter valve (typical cos £80) you need the washer/o ring kit. Though this is usuall unobtainium. Some diverter valve replacements include the kit but som don't.

You can get the real macoy from HRPC, or you can get cheap supplie from

is a nightmare job for the uninitiated and an nasty one for thos of us trained to do it. Round here we charge £100 labour for that jo and some days we wish we hadn't started it.

Usually when they go wrong it's only the diaphragm, but the stupi manufacturers build them in such away you have to remove the diverte valve (in most cases) to get at the diaphragm.

You have to isolate flow and return and cold feed. Open blow off valv manually to drain boiler, dump the remainder on the floor aroun boiler while you undo nuts and it gurgles out, catch what you can bu have a few towels ready. If yours has o ring seals and you can't fin replacements sometimes high temperature silicon grease might b sufficient. Where there are fibre washers you really need to find ne ones, but if you c

-- Paul Barker

[Paul Barker]

If it's just a leak you don't need a new diverter valve (typical cos £80) you need the washer/o ring kit. Though this is usuall unobtainium. Some diverter valve replacements include the kit but som don't.

You can get the real macoy from HRPC, or you can get cheap supplie from

is a nightmare job for the uninitiated and an nasty one for thos of us trained to do it. Round here we charge £100 labour for that jo and some days we wish we hadn't started it.

Usually when they go wrong it's only the diaphragm, but the stupi manufacturers build them in such away you have to remove the diverte valve (in most cases) to get at the diaphragm.

You have to isolate flow and return and cold feed. Open blow off valv manually to drain boiler, dump the remainder on the floor aroun boiler while you undo nuts and it gurgles out, catch what you can bu have a few towels ready. If yours has o ring seals and you can't fin replacements sometimes high temperature silicon grease might b sufficient. Where there are fibre washers you really need to find ne ones, but if you can't you could try making gromets with ptfe (wrap i around finger). Or the time honoured cure all boss white and hemp.

effing good luck you'll need it

-- Paul Barker

[ds]

Just spoke to the technical dept on Vokera's customer helpline and they've confirmed that i need a new o ring (part number 0716). Curzon (who do on-line sales at

has an outlet close by so i'll pick one up tomorrow morning before work.

Engineer on the phone said that if i remove the two bolts which screw towards the centre, beside the part he called the manifold (the disc shape thing), it should separate from the manifold and i should see the o ring. Apparently this pipe/valve i am loosening is only meant to have two bolts in it, even although it has threaded holes for four.

Cheers for your advice & tips Paul about replacing the o ring. By the sounds of it, i won't be able to get it finished without help - however will give it a go, and make sure i have hi-temp sealant at the ready.

Probably give it a go tomorrow night.

cheers

Daljit

[Paul Barker]

If you procure the correct or ing you just need a lubricant when yo assemble it, we use spit. in my post I mentioned ht silicone grease that was not instead of an o ring but to accompany reassembly of th existing o ring. New o rings don't require anything but a small amoun of lubricant (spit) to ensure they are not snagged on assembly.

Sounds like you could manage it alright. remember to open up all thre isolations after you've done job, refiull from filling loop, turn of gas valve, run boiler to clear air locks in heat exchanger, pressin reset as required run it let it rest run it let it rest etc etc unti no more air sounds. Turn on gas valve, let it light, Bob's yer uncle

-- Paul Barker

[ds]

Hi

Success!

Fitted the o ring last night without any problem. Whole thing took less than 45 mins to do (inc emptying out the cupboard to get into the boiler!). Manifold (or diaphragm?) came away easily when i removed the two bolts, and i just slipped the (tiny) o ring over the 4-5mm pin thing sticking out (couldn't see any other place for it to fit). Didn't need to use the sealant as first re-assmebly seemed to work. CW supply and boiler was switched on following repair - no evidence of any leaks this morning.

Cheers for you help, Paul.

Daljit