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Airco/vacuum lines/warm air/leak.

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tomatoes4all
Posts: 74
Joined: 1 January 2011
Year and Model: XC70 D5 MY2010
Location: Newcastle, New South Wales, Australia

Airco/vacuum lines/warm air/leak.

Post by tomatoes4all »

Hi all,

I have 4 issues, (well, my car does, I have a few more... :D ) which are all related, but could I use your collective brain to guide me along, please? My cold air from the airco is not cold anymore, which is probably just a refill. Correct? The next one is vacuum related: when accelerating somewhere in the dash something groans/sighs, like grandpa used to do when he got up from his comfortable chair, exactly the same sigh. Upon easing off the accelerator the sigh returns. During this the blower fan stops blowing cold air and returns after the aforementioned sighs. During uphill driving the fan stops altogether until the top of the hill, which makes for very hot driving, it is summer here down under.(I have read the posts, seen the movie, did not get the t-shirt yet, sorry, I digress). I understand the vacuum lines/ solenoids opening and closing the flaps, but all flaps work well in my car, the cool/lukewarm air flows where I direct it to go, all is OK there. The last issue is the leaky condensor, at least that is what I think that is (please see picture), it is leaking/dripping from the bottom of the box. I have removed the glove compartment and the bottom cover, so all is easily accesable, but I don't know what to attack here. Can I just remove the bolts of the condensor cover and see if there is a leak there? Or could it be the condensor drain hose is plugged and as a last resort draining inside the foot well? The picture is of the passenger side/left footwell, as I am RHD.
The next picture is in the engine compartement, against the fire wall, behind the airco unit. Are these some of the vacuum lines mentioned in some of the posts dealing with the flap issues some other members have had? What are these little "pots" for?
Are all these issues as related as I think they are and what is the preferred order of attack here?
Thanks for your help, best regards, Erik
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billofdurham
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Year and Model: 855, 1995
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Post by billofdurham »

I'm going for the easy bits first.

Lack of cold air is usually an indication of a lack of refrigerant. If you haven't had this done for some time it may pay to drop it into an AC shop for a full check, especially leaks, as it is a waste of money to just top up a system which may have a leak.

The "pots" are non-return valves.

The condenser is in front of the radiator. The bit inside the box in the car is the evaporator. If you have liquid dripping out of the evaporator box it is usually because the drain tube is blocked.

Now to grandpa's groans/sighs. I make similar noises when I stand up so I can empathize. These noises are caused by the vacuum system opening and closing the flaps and valves.

There is a wide open throttle cutout relay in the system which stops the air con working on hard acceleration to give more power to the engine. However, I have not heard of the WOT relay stopping the blower fan. Does it actually stop or is it just a lack of cold air coming through that gives that impression?

Bill.
Work was good - retirement is better.

1996 850GLT 2.5 20v Estate Manual.
1995 Peugeot Boxer 2.5Tdi Autosleeper.
Previously:
1984 244DL, Manual, Beige.
1987 744GLE, Manual, Green.
1991 960 3.0 24v, Auto, Silver.
1994 940T Wentworth, Auto, Blue.

tomatoes4all
Posts: 74
Joined: 1 January 2011
Year and Model: XC70 D5 MY2010
Location: Newcastle, New South Wales, Australia

Post by tomatoes4all »

Hi Bill,
Thank you for your reply. The fan slows down, almost to a stop, when the WOT cut-out relay disengages the aircon, but still blows a little bit.
As for the evaporator: I will carefully slide the rubber off the drain and see if I can dislodge the obstruction. (I now realise that when I park the car after a drive with the aircon on full, it never leaves a puddle of water under the car from the drain, which is obviously blocked).
I will get a aircon repairer check the integrity of the pressure system, apparently with dye it is easy to find a leak if (there is one).
My cars grandpa noises might be from water in some of the lines, who knows..

I'll report back with my findings. Just received my Ebay copy of VADIS today; if it all works out I can do some more in-depth home work. A picture and the thousand words and such...

Thank you and best regards, Erik.

tomatoes4all
Posts: 74
Joined: 1 January 2011
Year and Model: XC70 D5 MY2010
Location: Newcastle, New South Wales, Australia

Post by tomatoes4all »

Issue solved!!
The system was low on refrigerant. The culprit was the fill port which was not entirely tight, and last years refill slowly leaked out. I had the system pressure tested, vacuumed out and refilled and is now cold as ice.
The "flaps" were not all closing properly due to a few leaves and other stuff being sucked against the flaps. There also was a lot of rubber foam particles in the duct system, which I vacuumed out with the fan on full.
It is not hot here for the next few days, but on the next drive on a hot day I will wear a sweater, turn the temperature controls all the way down and will enjoy the frigid air...
Should I use a sealant on the evaporator box or should it not leak anymore after the drain is now clear?
Thank you for your help, Best regards, Erik.

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billofdurham
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Year and Model: 855, 1995
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Post by billofdurham »

Should I use a sealant on the evaporator box or should it not leak anymore after the drain is now clear?
None of the books make mention of sealant. Any liquid inside should drain out through your newly cleaned drain tube. Put this job on your 'to-do list' for regular checks and you should have no more trouble.

Bill.
Work was good - retirement is better.

1996 850GLT 2.5 20v Estate Manual.
1995 Peugeot Boxer 2.5Tdi Autosleeper.
Previously:
1984 244DL, Manual, Beige.
1987 744GLE, Manual, Green.
1991 960 3.0 24v, Auto, Silver.
1994 940T Wentworth, Auto, Blue.

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