Hissing from pressure relieve valve

René T

My Londinium I has been working flawlessly until this week when I've noticed a continuous hissing sound in pressures greater than 0.6bar. Upon further investigation I think I have identified the cause being the pressure relieve valve (aka overpressure valve OPV). Direct auscultation over the valve via stethoscope reveals the hissing I'm hearing. It's also reproduced by gently moving the pin of the valve sideways. I'm quite sure it's not the vacuum breaker valve. Reading on the forums, there seems to be two common causes for this. a) scale that has formed on the membrane. I find this somewhat improbable as I've been using Volvic exclusively and have been bleeding water after extensive steaming. b) a broken spring, which also is kind of unlikely? I have taken the following steps: gently rotating the pin a quarter of a turn in either direction. The problem persists. Pulling the pin up slighly to dislodge scale. No success. Now I think I might have to remove the valve for further inspection.

Now before I do this I turn to your wisdom, people of Londinium. Is there anything I'm missing? Can you help me please?

Best of thanks!

Reiss Gunson

hi rene

thank you for posting

yes, i would trying turning it 1/3 to a half turn in either direction

also try lifting the nipple so steam escapes, turn it a 1/3-1/2 turn, then let go of the nipple abruptly and let it drawn down by the spring in the valve

basically you want to get that valve to reseat if at all possible

if not, you will need to replace it

i don't think you have had your machine a year, so i will replace it under warranty if it is needed

if you do have to replace it i recommend removing the water box

you can replace it without removing the water box, but it isn't ideal

kind regards

reiss.

René T

Thanks for the quick reply! Unfortunately despite my best efforts the hissing persists. I think I'll replace the valve. Is PTFE tape good for sealing the threads?

Reiss Gunson

Hi Rene

If you can survive for a week I will send you a valve from here, and also a bottle of the exceptional loxeal 55-03

I prefer it to ptfe tape

Kind regards


Reiss

Reiss Gunson

Can you please email or PM to confirm your address, email, and telephone are the same

Reiss Gunson

hi rene

i have just packed up these two items for you, and they will be collected today

i will also add the loxeal 55-03 back into our store as i think it is an excellent product, and not readily available




kind regards

reiss.

René T

So finally an update... The package arrived very shortly after this post - talk about service! Thanks!

Today I've finally attempted to replace the valve - and have failed. I removed the water tank as suggested. But no amount of force will loosen the lower nut, even with a fairly long wrench. I have tried both with a hot and cold machine. I considered torching up the nut but I don't have one available right now.

Any suggestions?

Frans Goddijn

Did you use a spanner of the exact size, or was it a wrench that can be adjusted (and thus may not have a perfect tight fit)?

"no amount of force" seems to suggest you pulled or pushed hard, but that would be a very wrong approach. You would not loosen the nut but with enough force you could disrupt the boiler.

Did you use a hammer to tap the spanner?

Reiss Gunson

hi rene

no need for heat. as frans says, strike the end of the spanner/wrench with a hammer with medium force. it needs to be more than a 'tap', but no need to be stupid about it either. start with a light-medium force and gradually increase the force of each strike until you see movement. it is helpful if you have someone to hold the boiler as you do this, but not essential

when you fit the replacement part take the same approach. i.e. do it up until the thread becomes more difficult to turn, then use 3 strikes of the hammer to finish it off. on the third strike you should be able to feel it coming up tight. use about the same amount of force that was needed to loosen the thread

it is only copper, so go gently - it isn't steel

please do FaceTime or Skype me if you wish - i am more than happy to provide guidance

kind regards

reiss.

René T

Thanks for the quick reply!

Striking the end of the wrench doesn't work. "No amount of force" means "less force than I assume is needed to break the boiler" - I have no intentions of having a piece of scrap metal sitting on my counter.

I have both a spanner of exact size and an adjustable wrench. Aiming for a rotation to the left. I'll get someone to hold the boiler soon and if that doesn't work I would be glad to consult with you Reiss.

Reiss Gunson

hi rene

just keep hitting it, gradually increasing the force - it will come free

it may have liquid ptfe on the thread and this will be clear and rigid

as long as you use a striking force and do not torque up the wrench you will not do any damage

as i said, please do feel free to call me on Skype/Facetime

kind regards

reiss.

Gregory Green

From my experience the word “hammer” gives the wrong impression, to me a hammer is a heavy slow moving object.

In this situation I’d be using a spanner of the exact size and strike it on the far end with a short sharp blow from the next size up spanner.

This is probably what you’re doing, but we all have our different methods.

René T

All is well now! A second person holding the boiler in place was essential in my case. The force needed was higher than I initially would have thought.

Thank you all for your great advice!

René T

So I've documented the process in case anyone needs it in the future.

0. Unplug the machine from power. Remove the side and top panels.

1. Remove the water tank.
a. first take off the bottom two screws




b. unscrew the four screws on the side of the water tank




c. take off the screw holding the Gicar in place




d. unscrew the tubing on the right side. Very little force required.




e. remove the now loose part of the water tank.

f. on the underside of the remaining part of the tank, disconnect the water tube.





g. either disconnect the two contacts on the bottom of the tank or just dislodge it to the left so it doesn't get in your way when you unscrew the valve

2. Remove the rear pannel (4 screws)




3. Get your spanner/wrench in place. Get an assistant to hold the boiler in place. Tap the end of the spanner (aiming for a rotation to the left) until the valve is unscrewed. It took me quite some force (about the force it would take to send a football 15 meters if punched by a fist at a 45degree angle if that makes any sense)

Attached files

René T

4. All done

5. Screw the new valve in place. Again tap the end of the spanner to secure it in place.

Repeat Step 3 to 0 in opposite sense.

Matthew Hoffman

Did you use a thread lock to secure the new valve?

Matt

Reiss Gunson

hi Rene

thank you for the photo essay

kind regards


reiss.