VR Vacuum leak from Aircon controls

[combatantsomeone]

hey all
just about at wits end.. XD
I have a VR acclaim s2 and there is a hissing noise coming from the back of the aircon control unit(where vacuum hoses connect)
It hisses with varying degrees of loudness depending on where the vent control is turned.
It doesnt hiss on foot or the cool on top and warm on the bottom setting but it does on all the others..
I have checked all the connections, replaced the entire set of vacuum hoses and tryed a different control unit..

Anyone got any ideas? coz im all out..

[combatantsomeone]

bumppppp
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[The1]

The rubber seal behind the selector knob wears out and doesn't seal, pretty inexpensive part to buy new from holden, just a bit of time fiddling to change it over, if youve replaced the selector and the hoses then either the hoses are on the wrong ports or the hissing is coming from somewhere else.

[combatantsomeone]

I tried a different (non hissing) control unit and mine still hissed. I didnt remove the hoses only that rubbery thing that they all connect into and it only goes on one way

[The1]

i dont know put some vasoline in the end of the hose connectors that connect the back of the selector to seal it more, it's either the hoses or the selector there's not much to it.

[combatantsomeone]

Good idea ill give that a try tomorrow even its only temporary shud at least identify the problem

[hako]

Also check the heater vacuum switch which is near the selector.