roca dual flush cistern

[desktop]

When I screw down the the cistern cover it seems to open the flush valve and releases a constant flow intio the bowl, resulting in 'ghost flushing'. Is the screw intended to incorporate some adjusting mechanism ?
Could I resolve this by shortening the screw ? at the moment I have temporarily resolved this by only partially tightening the screw.

 

[croydoncorgi]

The (black plastic Phillips head?) screw that holds the lid down goes into the top of the flush valve, so if tightening it pulls the flush valve upwards HARD it probably will leak!

No, the screw definitely does NOT include any adjustment. It is supposed just to secure the lid.

My guess would be that for some reason your cistern is a tad deeper than intended (or maybe you're just over-tightening the screw). So long as the lid won't lift off, it's tight enough.

 

[Newboy]

It may be that the one (or both) of the two rods behind the button are a little over length - when you tighten the lid down this has the effect of just starting to open the flush mechanism. Check the rod length carefully - I seem to remember that Roca provide a guage to ensure correct fitting

 

[chalkywhite]

Hi, thanks Newboy and croydoncorgi !

I just performed the maintenance recommend by the Roca Laura manual (yes, i hoard everything!) and that involved cleaning/replacing the bottom washer - it was covered in light green gloop.

After assembling the flush mechanism, but before replacing the top, i filled the cistern and no excess water entered the pan. After the first flush with everything screwed back in some water did trickle into the pan after the cistern was full, but i'm not sure whether it was me playing with the button (sharp taps on them) or perhaps there is always a short trickle after the flush, as the ghost flush stopped.

If I find that further flushing causes the trouble, I'll try loosening off the screw a bit, and looking to shorten the plastic rods under the buttons. p.s the manual gives a gauge for the big blue centre piece which slides up and down the column, but only gives illustrations for the rods on top.

Many thanks for this advice and this forum!

 

[longdogs]

If you have to shorten the rods and accidently cut them a bit too short, ring the manufacturer and they will normally send a replacement free of charge.

 

[chalkywhite]

Thanks Squeaky, it appears the cleaning made no difference, but loosing off the screw holding the lid to the cistern has made some difference,

I'll keep an eye on it. We're on a water meter, so water trickling down the pan 24x7 will bite us in the bum before long!

 

[chalkywhite]

Nightmare times. Twice I've come back from home in last two weeks thinking I'd cracked it, and both times the inlet was almost fully open allowing water to flow straight from cistern to bowl, ALL DAY

I've cleaned all but the fussy placky dual flush mech at the top of the cyphon, and have noticed that the blue round bit in the centre doesn't always sit at the right height, it falls to the bottom. The whole stem inside the contraption is at an angle too. Piccy here hopefully?

http://www.photobox.co.uk/album/6901846

I've now left the lid off, and neither button allows for a full/half flush, just a splash into the bowl. Any ideas before I call my local plumber? Would this be covered on Brit Gas 3* services thingy, i wonder?

Cheers everyone!

 

[stevebee]

Hi,

I had the exact same problem as you have experienced about a month back and came across this site when looking for a replacement valve part. When I was troubleshooting I found that the water level sits at or slightly above (3mm) the marked water level mark in the cistern.

The blue part in the the centre I think determines either the sensitivity of a flush being triggered. With it positioned lower down it will cause the water preasure to be greater acting on it. I tried moving it nearer to the top of the center console to make it less sensitive but found that it didn't make too much difference.

The reason behind this I believe is, when the unit flushes the center stem part is released up to release the water then back down to hopefully make a good seal with the cistern. I noticed that if the stem does not go back down exactly straight then the rubber seal does not make good contact with the cistern and lets water out the pan. You can test this out by slightly pressing against the stem in a horizontal direction and you will see the water leak out to the pan.

In the end I decided to fit a Geberit Universal Dual Flush Mechanism replacement valve to resolve the issue.

http://www.kirkbys.co.uk/cgi-bin/trolleyed_public.cgi?action=showprod_282350KD1

This is a post where I got the Gerbit idea

http://www.diynot.com/forums/viewtopic.php?t=22965

Hope this helps and is not too late a suggestion.

Cheers, Steve.

 

[chalkywhite]

Hi SteveBee, and no it's not too late for the advice.

I've had the lid off the cistern since i last posted, and a screwdriver at the ready incase the problem persists to shut the valve off.

I'm finding that with the lid off and blue object in the correct place, both buttons appear to work. Perhaps the lid assembly screwed to the centre column is contorting the contraption, and therefore leading to the wonky seal you talk about?

Does the Gerbit device look a lot better built? Most people on here say that Roca gear is rubbish.

Thanks, Tony

 

[Plumbum1]

Help!!!!!
Water continues to run after I flush.
Problem--How to remove the cistern lid to see the problem.
There are no visible screws and I fear forcing things will damage the mechanism.

 

[chalkywhite]

This info is already available on this forum through a search, but here goes again.

Press down either flush button slightly, lift the other button up and out, then the first button will come up. A black screw sits under both, undo this, then remove the lid.

 

[Plumbum1]

Sorry to be a pain but I did look for the problem before I posted.
My lack of technical jargon is possibly the reason I could not find it.
Any how Chalky, so far so good, I've got the lid off and will now search the forum for an answer to how I can get the stop cock to cut off the water.
Many,many thanks Chalky.

 

[chalkywhite]

Didn't mean to sound so blunt.

You could either string the inlet arm up/down to stop the water entering the cistern, or most modern fittings have an in-line valve on the pipe leading to the cistern. If you have the latter, then you should see a screw head on the valve, which you can turn with a screwdriver through quarter turn, and listen for the water to stop.

Hope this helps you have a more stress-free Xmas!

 

[Plumbum1]

Eureka!!!!
Found the answer on here. Water now stopped. Thanks a million everybody. I hope you all have a lovely Christmas.
XXXXXXXXXXXXXXXXXX
Sandra

 

[chalkywhite]

Hi,
In the end I decided to fit a Geberit Universal Dual Flush Mechanism replacement valve to resolve the issue.
http://www.kirkbys.co.uk/cgi-bin/trolleyed_public.cgi?action=showprod_282350KD1
This is a post where I got the Gerbit idea
http://www.diynot.com/forums/viewtopic.php?t=22965
Hope this helps and is not too late a suggestion.
Cheers, Steve.

Hope Stevebee is still using this forum. I've decided to replace with a Geberit, but my plumber asks me to check the size at the bottom of the flush mechanism, he mentioned 1.5" ?? How do i know if the universal one will fit all, and be truely universal if the hole through the bottom of cistern can be varying sizes?? Thanks