Hissing sound once LR is turned off

Rob West

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

Reiss Gunson

of course its not normal.

what pressure is showing on the boiler pressure gauge?

Rob West

I think it is 1 bar. The pressurestat kicks in around 0.8 bar.

Reiss Gunson

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

reiss.

Reiss Gunson

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)

Reiss Gunson

Rob West post=15609 wrote: I think it is 1 bar. The pressurestat kicks in around 0.8 bar.

good. normal.

Reiss Gunson

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

best

reiss.

Rob West

I think it might be the vacuum breaker?

[video width=425 height=344 type=youtube]BCT8WnsJOnQ

Rob West

Definitely the anti-vac valve. If I depress it the hissing stops for a bit. I guess I need to replace it?

Reiss Gunson

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

Reiss

Rob West

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.

Reiss Gunson

Push it down further: it will open. Let me know please.

Rob West

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.

Reiss Gunson

Pull it off and take a look

Either a damaged o-ring, damaged ptfe seat, or a piece of debris

Rob West

Is it straightforward to remove? Anything I need to be aware of when doing it?

Rob West

Just seen your post on my other thread with instructions, so no need to reply here, thanks