Air Con Hissing

[benjgorman]

Hello,

I have a 2017 Berlingo Panel Van (SWB). Last week my air-con started hissing, before there was no hiss.

Here's a video: https://drive.google.com/file/d/1pBSfdZu...share_link

I've seen online that I may need to re-gas it? Another berlingo group said "...turned out the condenser had gone, pin hole £250 for a new including the regas".

Any way I can check what's going on easily?

Cheers,

Ben

[Sol]

Not likely you can do anything to test it yourself, the gas is poisonous and you need the proper kit to test it for leaks but it's probably empty now. It only holds a small amount of gas in liquid form.

Maybe the kit from Halfords would stop the leak and re-gas it but when its gone, you need the leak repaired (component replaced) and then a vacuum pulled on the system to dewater it and allow the gas to be refilled. You need to use the correct gas for your system (it changes all the time over models and years) but you can find that on a sticker near the inner wing on AC models usually.

[benjgorman]

So you reckon it's defo a leak? It's odd when I'm driving and it gets to above a certain rev amount sometimes it seems to go away and then come back (sometimes when I'm going up hills).

[Sol]

The only other thing could be belt hiss if it's not a gas leak, they only contain a small amount of gas so it is was leaking it would be empty in a day, even a tiny pinhole would drain it over a day or two.

Maybe the belt is making a noise on the pulley.

Ah....wait, your hearing the turbo that's all. I can hear mine and it's a shhhhhh sound as the boost builds. Especially up a hill - that's when it builds boost hardest and early but the sound rises in pitch with revs. 

Starts about 1500-1800 and gets higher pitched until 3000 rpm then stays steady. It's the turbo.

Not certain it's an issue to bother about -  normally you don't hear them spool on the Berlingos (my previous 3 were not audible) but this one (2017) is definitely audible when it spools. I think because it has no doser unit on this year, and it boosts straight into the intercooler. Or I have a little boost leak. Maybe you do too.

[benjgorman]

Ah ok maybe a gas leak then, will a refill fix the pinhole or not? I had a look through the bumper to see if there was any noticeable issue with the condenser but didn't notice anything (e.g., if it was stone damage)

I don't think it's anything to do with the Turbo, this hiss is audible when it is idling and parked with the aircon turned on. The hiss goes away sometimes when I get up to speed or up a hill which makes no sense to me, oddly when I turned the van on yesterday to check things, there was no hiss and it was parked in sunshine, so perhaps something expands with heat and fills the pinhole?

[Sol]

Gas is very good at escaping; hard to imagine it only getting out sometimes. Most likely sounds like belt hiss when the AC clutch is engaged - from the increased load. If it still blows cold air on full AC, then it is probably that, and not a leak.

[benjgorman]

Well - turns out I was just low on gas. Passed the vacuum test first and then 12g was left and they filled it back up to 450g!

[Sol]

Good result; where did the gas go that was in it lol.