s212 air suspension - what should happen?
Thread Starter
Member
Joined: May 2018
Posts: 214
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From: SoCal
2020 E450 4matic wagon
s212 air suspension - what should happen?
Greetings all 212 owner/operators,
Interesting event occurred February 2023. Began a 6 hour drive from home (SoCal 68°F) to the Sierras (5°F) and parked the car in the sub freezing temps for three days.
Contributors, nominally, what should happen to the height of the air bladders when I parked and left it cold soaking for three days?
a) decrease in height (i.e. pressure) i.a.w. PV=T
or
b) remain at same height
Interesting event occurred February 2023. Began a 6 hour drive from home (SoCal 68°F) to the Sierras (5°F) and parked the car in the sub freezing temps for three days.
Contributors, nominally, what should happen to the height of the air bladders when I parked and left it cold soaking for three days?
a) decrease in height (i.e. pressure) i.a.w. PV=T
or
b) remain at same height
Last edited by mercerized; Feb 3, 2024 at 06:42 PM. Reason: clarification
Out Of Control!!
Joined: Apr 2019
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From: Silicon Valley
W212 MY'14 M276-3.5NA @75kMi
wet air freezes
Normal air contains moisture, compressed air contains condensate. Same H2O that's known to expend below freezing.
That can play a number on rusted valves or air bags.
You know in Winter truckers are forced to use a special alcohol fluid to dry the air of their brake lines when crossing the Sierra Nevada. Frozen air lines are a real problem when water expends.
I wonder who knows how the Airmatic deals with condensate discharge ??
That can play a number on rusted valves or air bags.
You know in Winter truckers are forced to use a special alcohol fluid to dry the air of their brake lines when crossing the Sierra Nevada. Frozen air lines are a real problem when water expends.
I wonder who knows how the Airmatic deals with condensate discharge ??
Last edited by CaliBenzDriver; Feb 3, 2024 at 10:13 PM.
Thread Starter
Member
Joined: May 2018
Posts: 214
Likes: 66
From: SoCal
2020 E450 4matic wagon
My theory is that the temperature of the slug of air during the six hour drive likely was somewhere around the ambient temps 40 to 50°F because most of the drive had an OAT about that. The last hour of the drive decreased to sub zero and that's when I parked for the next three days.
So, I think that answer is a) decrease in height because the slug of air decreased in pressure from the cold soaking.
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2010 E550, 273 Engine: 2012 S550, 278 Engine
The pressure in the air springs does not change. It comes from the weight of the car. The volume of air goes down with lower temp so the car will lower down as the Airmatic does not run the compressor (smart) when car is not running.
Thread Starter
Member
Joined: May 2018
Posts: 214
Likes: 66
From: SoCal
2020 E450 4matic wagon
However, if the car is nearly bottomed then it's highly probable that the air pressure in the bladder has decreased - all likelihood this situation is a combination of decreased pressure and volume.
