Izzo Vivi PID III "Gurgling"

[koffeinberiget]

My Izzo Vivi PID III has been making a gurgling sound for an embarrassing number of months now. I think this also consumes water from the boiler, leading to the auto-refill running more frequently. Today I finally took a stab at it. Replaced the little rubber gasket/seal in the OPV (on my mate's recommendation), but that didn't help.

Upon closer inspection, it seems like there's leakage from what I believe is the boiler anti-vacuum valve. I made this little video demonstrating:

Can someone a) explain to me what the anti-vacuum valve does and b) could this be the culprit.

An alternative theory is a faulty/scaly water level sensor, leading to overfilling of the boiler.

[HB]

Can someone a) explain to me what the anti-vacuum valve does and b) could this be the culprit.

a) See Can someone please explain false pressure? and b) definitely. For easy reference, here's a copy of my reply from La Cimbali M32 Dosatron problem with water that describes the same problem as your gurgling:

A vacuum breaker is a valve with a weighted piece that is pushed up by escaping steam when the steam boiler heats up. This lets air escape so the steam boiler is filled with saturated steam, not a mixture of steam/air. When the steam boiler cools, the weighted piece falls, opening the steam boiler to the atmosphere so it depressurizes; without this valve, the steam boiler would be under vacuum since the water volume decreases as it cools.

These simple valves may stick closed, leading to "false pressure", or they may fail to close completely, leading to drips/slowly escaping steam. Based on what you've described, your task is figuring out why it's not closing completely. Cleaning them with white vinegar usually resolves the problem, but the sealing surfaces can wear too, in which case it's a repair/replace situation.

There are hundreds of prior discussions if you need more guidance; search on "vacuum breaker" or "false pressure". Here's a handy photo of a vacuum breaker. The item labeled (1) is the weighted piece I described and it seals against the item labeled (3); the item labeled (2) screws into the boiler and is capped by the unlabeled item.


From Vacuum breaker - serviceable?

[koffeinberiget (original poster)]

Thank you, Dan. A new vacuum breaker is on order, and should arrive tomorrow. I'll make sure to update the thread once it's been fitted.

[koffeinberiget (original poster)]

Finally found time to perform the procedure! Two spanners, a new zip tie and some PTFE tape. Tighten until it goes soft, then back off a quarter turn.



The old one was a bit tired: