# Machine constantly hissing



## khampal (Feb 6, 2017)

There's a small black pipe that goes into my drip tray. When I first bought my QM Rapida a month ago, it would hiss for a few seconds when the machine was warming up or cooling down around about the 100c mark. It used to let off about a spoons worth a water into the drip tray each time. However, recently, it's gotten more frequent and larger amounts of water have been left in the drip tray. Today, my machine has been hissing all the time whilst its been on with the pipe into the drip tray constantly dripping water. Any ideas what this pipe might be for, and what's causing the noise?


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## Nikko (Aug 20, 2014)

Anti vacuum valve not sealing.


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## khampal (Feb 6, 2017)

Thanks, do you know why it might not be sealing?


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## espressotechno (Apr 11, 2011)

Remove the lid & look / listen.

If the anti-vac valve is leaking steam, it's usually due to the internal rubber o-ring splitting or scale around the spindle.

If it's the safety valve hissing then just fit a new one.

Both items are cheap & easy to fit (on a cold machine, unplugged from mains !).


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## khampal (Feb 6, 2017)

Thanks for the replies. Which part is actually the anti vac valve? The part that's connected to the drip tray is connected this thing:

















Seems to go 4 ways. One goes directly from the boiler, another to the manometer. The bottom (with a down arrow) and top connections (with some word that looks like MA TER) are connected to each other via a T shaped connector which goes off to the drip tray.

Thanks


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## khampal (Feb 6, 2017)

Looks like its the whole thing:

https://www.bellabarista.co.uk/vacuum-breaker-safety-valve-for-quickmill-verona.html

Pretty pricey to replace, let's hope elektros will send me a replacement under warranty


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## El carajillo (Mar 16, 2013)

The one on my Verona went the same way, I did strip it down but they are not serviceable. Only choice new one


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## espressotechno (Apr 11, 2011)

These combined safety/anti-vac valves are always an expensive nuisance (a Reneka combi valve costs over £100)


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## DavecUK (Aug 6, 2013)

El carajillo said:


> The one on my Verona went the same way, I did strip it down but they are not serviceable. Only choice new one


They can sometimes be opened up and serviced....the OP just needs to be careful NOT to rotate the valve assembly itself. If this happens it can cause the O ring which seals the 2 parts of the main valve body together to leak. I have fixed a few of them in my time.

*Part A is the vacuum breaker, probably the part that's leaking. That is removed by undoing the small nut just at the base of the spout, the stuff in there can be easily cleaned....there is no O ring, just a spring and a teflon seat and pad. Usually cleaning this will get it working leak free. You could even put some citric acid solution inside using a drinking straw dropper, or Q tip.*

Part B is the safety valve assembly and I doubt that part is leaking.

If there is a his from the area where the two parts of the valve body join (shown by the 2 big arrows...then that O ring is leaking and is not servicable (for normal users). Of course if you have silicon O rings the right size and knew what you were doing, then you could service it I suppose.

Dave


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## khampal (Feb 6, 2017)

Thank you Dave, that's very useful


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## iulianato (May 5, 2015)

You can find O-rings of any size on ebay, including food grade if needed. Good luck


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