ph1 Air-con didn't work, now does but..

[DanDare]

At 7am Sunday I set off on a 1hr 30min trip, within 15mins all the windows started steaming up, even with the fan speed on 3. The a/c was on since I'd set off. It took ages for the side rear windows to clear. I fiddled with the temp coming from the centre vents with the a/c on & off but it never seemed any colder either way. When I arrived I left the engine running whilst pressing the a/c button on & off but there was no clicking or engine revs drop as I would normally get. The outside air temp was 3-5degs.

I booked it in to be looked at today, I tried the a/c again before I set off & bu*#er me it worked ! The outside temp today btw was 5degs. The garage (who specialize in a/c systems) suggested some a/c's won't cut in if the outside temp is too low, does anyone know if this happens on 172's as I've ran this car through 2 winters using a/c regularly & this hasn't happened before.

Thanks.

 

[pupster92]

its french, it has its moments. just put it down to that unless it does it again

 

[TheEvilGiraffe]

They're right - the compressor on any modern car will not run under certain temps... something like 4deg C. I'm not sure exactly. Perhaps you've just neglected to notice before.

You do realise that a/c works the same if it's hot or cold ? It's simply a dehumidifier hence it clears damp windows wether it's blowing hot or cold. Apologies if you did already know that - maaaaaany people have no idea about this and assume a/c only 'does' cold.

 

[DanDare]

You do realise that a/c works the same if it's hot or cold ? It's simply a dehumidifier hence it clears damp windows wether it's blowing hot or cold. Apologies if you did already know that - maaaaaany people have no idea about this and assume a/c only 'does' cold.

Yep, I do know as I have it on (warm) through the winter too. I'm just unsure why the condensation seemed so bad for over an hour on Sunday & I've never had that happen before.

I'll carry on & see how it goes OK over Xmas, ta.

 

[TheEvilGiraffe]

If you were driving, the windchill at 50+mph is pretty intense.. depending where the sensor is, it might think it was below the cut-off zone.... who knows !

Good luck !

 

[DanDare]

Could the sensor be faulty ?

 

[DanDare]

Well almost 2 weeks after this first happened, & the air con having been working fine for the last 9 days (100's of miles, a/c on most of the time) today it stopped again, it worked this morning but packed up this afternoon. Light comes on when button pressed but no 'click' & steamed up windows. Today was 7-9degs btw.

It's obviously not a leak, could it be a faulty external temp sensor (assuming there is one) ?

 

[MikeClio172SPT]

Well almost 2 weeks after this first happened, & the air con having been working fine for the last 9 days (100's of miles, a/c on most of the time) today it stopped again, it worked this morning but packed up this afternoon. Light comes on when button pressed but no 'click' & steamed up windows. Today was 7-9degs btw.

It's obviously not a leak, could it be a faulty external temp sensor (assuming there is one) ?

First thing i would do.... if your not hearing the click... pull the plug off the compressor, insert the probes of a multimeter..... hit the AC button, & see if you are getting the feed to the compressor clutch.

 

[DanDare]

I had the system checked out today, turns out there was no gas left. Believe it or not a plastic clip located too close to one of the alloy a/c pipes near the left suspension turret has been rubbing & gone right through it !

Slightly miffed that should happen, & doesn't really explain why it appeared to start working for 9 days then stop again :dapprove:

Was quoted £225 just for a new Renault hose, though they have an engineering Co. nearby & said they should be able to sleeve/weld the hose & guarantee the repair, I'll see...

 

[MikeClio172SPT]

Dont be miffed, as the system can still operate if the Gas quantity is low, but it just has to be enough for the pressure switch to switch the system on when u hit the AC button. Also Pressure in the system can change depending on Temperature from the engine bay heat, & ambient temperature, With temperature changing, & your system low on gas, the pressure rising in the system from temperature change, was enough to operate the pressure switch, but probably your Aircon wasnt that cold either?? Also you say a pipe chaffed through, once the system has a leak, the gas would be gone & wouldnt operate at all at any time.