Universal Vacuum Valve 1/4 Brass hose  €7.19

Brass 1/4" anti-vacuum valve with a vent for silicon tube
 

Description:

This valve will have failed, if lime builds up inside causing it to stay open - you would hear a constant hiss if it is stuck open.

It's a quick and cheap fix - use PTFE tape to make the seal - see below.

You may need a new valve if:
- Steam escapes from the valve when the machine is on - constant hissing. Typical of older machines or when the boiler has lime buildup.
- No steam from the steam wand, but hot water comes from the coffee groups.