This forum is now read-only

To login to the new support channel and community forums, go to the Support Portal

Hissing sound once LR is turned off

After turning off my LR it is hissing for 5-10 minutes. You can hear the sound in the video. Is this normal? Thanks

[video width=425 height=344 type=youtube]CtWgpLfnv-U


  • of course its not normal.

    what pressure is showing on the boiler pressure gauge?
  • I think it is 1 bar. The pressurestat kicks in around 0.8 bar.
  • ok, so remove the top panel and both side panels and turn the machine back on and look for the source of the steam leak, looking into the light helps in this regard.

    hopefully it goes without saying that it is 120V (240V) inside the casing so please unplug the machine from the power supply before placing hands or tools inside the casing.

    kind regards

  • its a steam leak so focus your attention on fittings connected to the top third of the boiler, the pipe from the boiler to the steam valve, and the fine pipe from the boiler to the steam gauge (be careful with this one as it is the most delicate)
  • Rob West post=15609 wrote: I think it is 1 bar. The pressurestat kicks in around 0.8 bar.

    good. normal.
  • if you are struggling to see the steam take a cardboard tube that kitchen cling wrap comes on and place one end to you ear and move the other end around likely looking locations on the boiler

    using this low tech but effective method you will locate the source of the leak

    im off now as its 22:30 friday night but i will check in about 6am tomorrow

    if in doubt please wait until i am back online


  • I think it might be the vacuum breaker?

    [video width=425 height=344 type=youtube]BCT8WnsJOnQ
  • Definitely the anti-vac valve. If I depress it the hissing stops for a bit. I guess I need to replace it?
  • The anti vac valve is the short stubby one

    If you depress the valve stem gently with something like a pencil or wooden spoon so you don’t get a steam burn the valve will open and a jet of steam will shoot out

    Do you mean the anti vac valve or the safety valve, which is much taller at about 60mm

    Kind regards

  • Yes I mean the short stubby one, if I depress it with a pencil it stops the hissing. Seems a bit hit and miss as to whether it stays closed.
  • Push it down further: it will open. Let me know please.
  • Yes, it does open fine when I press it and there is a jet of steam. It is more that it then doesn't close fully and sometimes starts hissing again.
  • Pull it off and take a look

    Either a damaged o-ring, damaged ptfe seat, or a piece of debris
  • Is it straightforward to remove? Anything I need to be aware of when doing it?
  • Just seen your post on my other thread with instructions, so no need to reply here, thanks
Sign In or Register to comment.