# Hissing Heavenly



## Steve_S_T (Dec 7, 2012)

My Heavenly was serviced by Fracino two or three weeks ago. When I turned it on yesterday (it's only really used at the weekend) I noticed a hitherto unheard hissing noise. I've had a look under the hood this morning and can see that the hissing is coming from a valve on top of the boiler (FC134 according to the Heavenly parts diagram). Hopefully I've managed to attach a video showing the valve and the hot water bubbling out of it. Simple question is whether anybody can identify the solution to this problem without me having to take the whole machine back to Fracino.

Thanks in advance,

Steve.


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## Steve_S_T (Dec 7, 2012)

Ahhh, seems like I've only attached a photo, but it's the little silver valve on the left.


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## 4515 (Jan 30, 2013)

sounds like the pressure relief valve isnt seated correctly

a sharp tap on the top of the valve should fix it


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## Steve_S_T (Dec 7, 2012)

Thanks Working Dog. Didn't even need much of a tap, just pushed it with a screwdriver, it let out a puff of hot air then the hissing stopped. Any idea what causes that to happen, does it suggest the valve mighty be on it's way out?

Thanks again,

Steve.


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## 4515 (Jan 30, 2013)

Dont think its a valve on its way out. I think its more a case of the valve not being fully seated


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## El carajillo (Mar 16, 2013)

It is the vacuum valve, this permits air in and out on heating and cooling. As WD said just not seated correctly, if it does it again just check for a tiny bit of debris in valve seat.


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## espressotechno (Apr 11, 2011)

If it was serviced by Fracino recently, then the rubber seal inside the anti-vac valve will be OK. So probably a bit of debris stopping it sealing properly.


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