Gerberit Impuls260 Twico 1 flush valve - problems

[N3JTH]

In 2003 i refitted the bathrooms in my house and i had 3 new Ideal Standard WCs fitted, all of which have the same a dual flush valve. (Which turns out to be a Gerberit Impuls 260 or Twico 1. depending which website you read)
Like all the other postings i have seen here these leaked constantly when first fitted. But we got used it and it seemed to stop!
In the last few months we have a new problem. The flush has slowly stopped working, firstly it was the half flush which didnt work and then a few week later the full flush has become difficult. Interestingly, this problem started in the most heavily used WC and has now manisfested itself in the 2 second most used. I have had both of flush valve cartridges out of the cisterns and they both seem to function, however once in the cistern full of water the just wont lift to start the siphonic action. THinking laterally i have tried the cartridge from the 3 WC which still works into both other cisterns and it flushes.
So is the answer to replace the whole flush valve cartridge? (at £40+ each?) or are there seals i should try first? Is 6.5 years the life span of these items, which seems ridiculous the old fashioned valves used to go on working for generations!
(incidently the water levels and the filler mechanism are all working well so it's not that!)
Any help would be gratefully recieved!

 

[LUNAT]

HI

please send pictures for accurate reply .

 

[ww3361]

I've only just found this post but have the answer to your problem!

Disconnect the faulty flush valve from its basket.

Turn it upside down so that the actuating buttons on the top are now facing downwards.

Repeatedly press the flush buttons and observe the plastic internal levers, immediately below the buttons, within the housing, twisting and pulling.

These internal levers may appear to be carrying out their function: pulling the valve up to initiate a flush, whilst in your hand and outside of the cistern.

However, as you said, the moment you place the valve device back in the cistern and it fills with water it ceases to function.

Again, whilst upside down and in your hand, continually press the buttons and observe the internal levers BUT this time place some light resistance against the movement of the blue round thing that moves up and down on the central column within the flush valve device.

NOW if you observe the internal plastic levers immediately below the flush buttons you will see that one of the plastic levers has actually snapped or at least loosened (visible as you simultaneously press the button and resist the blue thing), resulting in the force applied to the flush button not being transfered though the rest of the device.

I.e. with the small amount of water pressure that's present when the cistern is full the flush valve no longer functions.

Solution; you need a new flush valve. Ask geberit what the warranty period is, as I agree these plastic levers are pretty hopeless.

 

[EssexAndy]

I've only just found this post but have the answer to your problem!

Disconnect the faulty flush valve from its basket.

Turn it upside down so that the actuating buttons on the top are now facing downwards.

Repeatedly press the flush buttons and observe the plastic internal levers, immediately below the buttons, within the housing, twisting and pulling.

These internal levers may appear to be carrying out their function: pulling the valve up to initiate a flush, whilst in your hand and outside of the cistern.

However, as you said, the moment you place the valve device back in the cistern and it fills with water it ceases to function.

Again, whilst upside down and in your hand, continually press the buttons and observe the internal levers BUT this time place some light resistance against the movement of the blue round thing that moves up and down on the central column within the flush valve device.

NOW if you observe the internal plastic levers immediately below the flush buttons you will see that one of the plastic levers has actually snapped or at least loosened (visible as you simultaneously press the button and resist the blue thing), resulting in the force applied to the flush button not being transfered though the rest of the device.

I.e. with the small amount of water pressure that's present when the cistern is full the flush valve no longer functions.

Solution; you need a new flush valve. Ask geberit what the warranty period is, as I agree these plastic levers are pretty hopeless.

I had this problem, did exactly what you described and yes the 'axle' that the levers rotate on was broken.
Nice one!

 

[arbitrary]

Same here - broken "axle" on a Gerberit Impuls 250. I felt/heard a click when flushing and then the buttons would only result in a trickle rather than a proper flush. If the buttons were held down long enough it would eventually flush

Temporary fix was to remove the cistern lid and then one or the other lever could be depressed far enough with a fingertip to get a proper flush.

New valve ordered from a UK ebay seller for £30 without buttons - that should do the trick.