VUW 824e - diverter or diaphragm

[Johnking]

Our Vailant VUW 824e boiler has gradually given up on giving us hot water. I have been told it could be the diverter valve or the diaphragm. I know what the diverter is and I think I could probably do it even with my limited plumbing experience. But what's the diaphragm and is it a DIY job?

We were quoted £220+vat which seems a lot to keep a 10 year old boiler going.

 

[Paul Barker]

Isn't Google easy?


Vaillant TURBOmax Plus 824E Boiler
Vaillant 252457 Hydraulic Valve
Mfr Part#: 252457 Ezypart Part#: EV01
To Fit Boiler Gas Code: 47-044-04 Vaillant £66.00

 

[Gasguru]

The boiler does not have a diaphragm but it does have a flow sensor that may have a fault.

Does the boiler fire up when you open a hot tap? If it does the flow sensor is probably OK. Feel the left hand pipe from the boiler - if it gets hot with just the hot water on the diverter valve is sticking. Hours work normally.

 

[gasgeezer]

The diaphram is in the divertor on a 10 year old model best to replace the lot
[divertor complete} they tend to leak. should take about 25 min when used to doing them, allow yourself an hour.I adjust the micro switch as well.

 

[Gasguru]

gasgeezer wrote

The diaphram is in the divertor on a 10 year old model best to replace the lot

But this boiler is a Turbomax with the water vane flow sensor. The previous models (VUW 242 series) had the DHW diaphram in the base of the diverter.

 

[gasgeezer]

I agree about the aqua sensor gasguru but not on a 10 year old boiler i think they did not change till about year 2000 onwards possibly the wrong info being posted.

 

[Gasguru]

The OP has told us its an 824E ie its only going to be a few years old.

 

[gasgeezer]

Also said it is 10 years old perhaps a bit of clarification needed before we can definetley diagnose.imho

 

[Johnking]

Gasgeezer is right, sorry chaps. I was told the wrong model number. When I took off the front it was labelled 282e. It does have a diverter valve, a large brass gubbins bottom right. The lever on the side of this was not operating the microswitch fully so the switch has been repositioned and it's ok now, but I suspect the divert might be on the way out. I have read that the diaphragm in these can be replaced. Can anyone suggest where I would get instructions for this?

Sorry again for misinformation.

John

 

[Agile]

Dont worry, most of us guessed what you had !

We would also charge about £200 and it can be quite a pig of a job if there is no access to the right and underneath the boiler.

It could take about 45 minutes if everything went really well but I always allow 1.5 hours as there are usually seized up screws and leaks to be dealt with.

If the lever is no longer operating the switch then its pretty easy to guess that the diverter diaphragm is on the way out and the whole valve will need replacing soon.

Tony

 

[ChrisR]

If the switch was greenish, =old diverter, don't bother just changing the diaphragm, change the whole diverter or get the refurb kit and change all its vitals.
Might take you half a day.
Someone could email you a manual or you can get a paper one from V, but it doesn't go into detail.
This is all it is:

If you don't fancy stripping it, buy a new one, which will still take you at least a couple of hours to fit first time

 

[Johnking]

Thanks for your help. I got pdf manuals from Vaillant, but as you say, light on detail.

In the meantime an engineer has moved the switch (which is green) a little and it's working most of the time now. Suspect it's only a matter of time though before the problem comes back. I quite fancy the refurb, I enjoy stripping things down and seeing how they work, but if I'm doing it myself I think I'll just replace it for time's sake. It looks fairly straightforward even for a novice like me.

Interestingly the service manual section for replacing the diaphragm doesn't mention draining down the system. Is this right, or do they omit it cos only a fool would do otherwise? Why not just replace the diaphragm on this particular one?

Cheers

john

 

[ChrisR]

That fact that the switch needed moving means that the DV isn't moving properly, usually.

The manual is right.

[code:1]Why not just replace the diaphragm on this particular one? [/code:1]
Because age and behaviour point to other things needing replacement within the DV, eg item 2,5,12.

 

[Johnking]

Can you do the refurb in the same way as the diaphragm, ie without draining down the system? or is it too fiddly?

 

[ChrisR]

Wouldn't try without taking it out before dismantling. Yes you'd have to drain for that.