Whirlpool Rapidjet air-control leaks water

[TimC]

Morning All,

Got a cliant with a whirlpool bath. When the jets are turned on the air control starts pushing out water. If I cover any one of the jets the water leak increases.

I would imagine there are non-return valves in the jets themselves to stop this problem and one, if not, all have failed.

Any thoughts please.

Thanks

Tim