Hi All

Here is my seek of knowledge.

260 E - 1992
North American Climate control.

Here are issues:

1.
Vacuum air Direction stuck in window ( upper position). On button press from window to salon center vents are empty. (side console vents are operating in all positions). AC (air temperature and blower fan) is working fine.

2. (may be correct behavior)
When put the window - defroster mode air is hot, when the temp switch on lowest cold setting.

Thanks for advices and directions

Remove the glove box. At the lower left of the glove box you will see a long manifold with a bunch of vac lines connected (this is called the switchover valve.) Remove the vac lines one at a time and connect an auxiliary vac source and check for leaks.

Five 'll get you ten, at least one of these lines will not hold a vaccum. If I am correct on that, remove the dash and replace ALL the vacuum pods. If one is bad, they all soon will be. Check all of them again at the switchover valve before putting the dash back together.

I suppose that it is fair to warn you that dash removal and replacement is about a 15 hour job.

Thanks

What else can be done / checked with dashboard parted?

How effective AC with duct up-to the window ?

I'm having difficulty understanding your symptoms and your questions. But if part of the problem you're experiencing is that A/C air comes out of the defrost vents at the windshield, you either have a bad vacuum pod or a leak in the vacuum circuit, causing the defrost vacuum pods to stay open, rather than closing as they are supposed to. (Incidentally, A/C air is never supposed to come out of the defrost vents, only ambient or heated air.) By design, the defrost pods are normally open, and it takes vacuum to close them. The other pods are designed the opposite way--to be closed until they're opened. So, if the center vents are not blowing air, one or more of the center vent vacuum pods is broken or a leak in the vacuum circuit (and, therefore, the pods aren't opening). The side vents are not controlled by vac pods, so it's normal for them to always be active. The diagnostic test for all of this is what Larry posted above.

__________________
1988 California version 260E (W124)
Anthracite Grey/Palomino
Owned since new and still going strong and smooth
MBCA member

Past Mercedes-Benz:
1986 190E Baby Benz
1967 230 Inherited from mom when she downsized
1959 220S Introduced me to the joys of keepin' 'em goin'

There are only 10 kinds of people in the world--those who understand binary and those who don't

Your description is somewhat cryptic to me, but just in case you are experiencing hot air from the vents when the A/C is on, you may have a simple problem with your mono-valve. It's the metal valve directly in front of your battery. It may be stuck open and letting in hot water when it's not supposed to. It's an easy fix. Disconnect the valve (two hoses and one electrical plug), plug the hoses or install a working one and see if that solves your problem. Even if it doesn't, you've just replaced a part that you would have had to likely replace very soon anyway. Keep the one you just replaced as a spare for one of your friends to use as a tester.

Now test to see if the climate control unit is the culprit by swapping it with one that you know works. Both the climate control and the mono valves are readily available used from the salvage yards and ebay for not much money. If that still doesn't solve your problem, then it's likely your pods and you'll have a large, though not impossible, project in front of you.

Hopefully one of the two tests worked and you saved yourself the dash and pod work for much later.

__________________
03 CLK430 Cabrio 211K Pweter Silver/ Oyster Leather
90 300SEL 214k Pearl Black/ Alto Grey/Black Leather

Prior: 85 190E, 88 300TE, 89 300TE, 90 300E 2.6, 90 300TE, 92 300E 2.6, 91 and 93 300SL, 87 Ferrari Mondial Cabrio