AC one side cold another warm. Please help!
#101
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Don't feed the trolls! I think he's just around to be my contrarian. He'd have a lot more fun on facebook.
#102
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1922 Ford Model T / no OBD
Your picture shows an old fashioned house heating radiator that has nothing to do with what cars A/C systems are built with and absolutely DOES NOT provide similar heat distribution. Your example is a parallel tubes connection while the heat exchangers in cars A/C systems are a single tube in "series" connection. And your picture is a "sales man's pitch" as without individual control valves in each leg it is not possible to have exactly the same heat exchange thru every tube. Situation in picture is not really possible in real world and from my own experience I can tell the far end of the radiator from the connections can run cooler during cold winter days.
A parallel tubes connection in cars does exist in the front of the car as the engine cooling radiator is built like that and it can have different temperatures and heat exchange ratios across the tubes but this has nothing to do with A/C.
A parallel tubes connection in cars does exist in the front of the car as the engine cooling radiator is built like that and it can have different temperatures and heat exchange ratios across the tubes but this has nothing to do with A/C.
I can't find as clear heat exchange picture for automotive evaporator, but heat exchanger is heat exchanger.
Here is the best automotive evaporator picture I can find. The coils loops, but the idea of heat exchange is exactly the same as on pictured above kalorifer.
Sorry if you can't understand it.
#103
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1922 Ford Model T / no OBD
Found another picture that might help you understand
#104
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What is your problem?
This picture explains exactly the same what I’m saying. One tube zig-zag thru the whole coil. All flow goes thru this same tube with fins attached to it. Every pass is connected to the end of the other so this is what I call series connection instead of parallel tube connection you present.
#105
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2008 E350 (W211 @170K), 2012 ML350 (W166 @119K), 2014 E350 Sport (W212 @96K), 2015 ML350 (W166 @92K)
Not to side with anyone here, but I think the point is that the evaporator (fancy for heat exchanger) does not have a uniform temperature throughout; therefore, there is a temperature "stratification/distribution" either side-2-side, bottom-up or in-between (each heat exchanger design has its own pattern) that impacts the flow distribution downstream into a plenum with flaps to control air distribution for the different branches of ducting (top, bottom, left, right combinations). It is up to the flaps to handle the non-uniformity of the air temperature in the plenum downstream.
I have not seen the air ducting for the W212 downstream of the evaporator step, but that is the only place I can see to control anything since the evaporator is a static system: inlet -> outlet
I have not seen the air ducting for the W212 downstream of the evaporator step, but that is the only place I can see to control anything since the evaporator is a static system: inlet -> outlet
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kajtek1 (09-20-2021)
#106
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Not to side with anyone here, but I think the point is that the evaporator (fancy for heat exchanger) does not have a uniform temperature throughout; therefore, there is a temperature "stratification/distribution" either side-2-side, bottom-up or in-between (each heat exchanger design has its own pattern) that impacts the flow distribution downstream into a plenum with flaps to control air distribution for the different branches of ducting (top, bottom, left, right combinations). It is up to the flaps to handle the non-uniformity of the air temperature in the plenum downstream.
I have not seen the air ducting for the W212 downstream of the evaporator step, but that is the only place I can see to control anything since the evaporator is a static system: inlet -> outlet
I have not seen the air ducting for the W212 downstream of the evaporator step, but that is the only place I can see to control anything since the evaporator is a static system: inlet -> outlet
#107
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1922 Ford Model T / no OBD
Glad you change your opinion Arrie.
#108
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Did not. My exactly is for the air flow handling.
When evaporator is running proper flow it gives pretty much the same temperature on the full surface. What changes temperature is the air flow thru it meaning outgoing gas is slightly warmer than ingoing gas right after evaporation. If you would measure the temperature on a coil without air flowing thru it the result would very much even temperature all over it.
On parallel tube system there is nothing to force the flow thru all of the tubes so you can have some tubes with much less flow that others. Can have tubes even without any flow. Series tubing (only one tube) makes sure the whole area of the evaporator (and condenser) is used.
When evaporator is running proper flow it gives pretty much the same temperature on the full surface. What changes temperature is the air flow thru it meaning outgoing gas is slightly warmer than ingoing gas right after evaporation. If you would measure the temperature on a coil without air flowing thru it the result would very much even temperature all over it.
On parallel tube system there is nothing to force the flow thru all of the tubes so you can have some tubes with much less flow that others. Can have tubes even without any flow. Series tubing (only one tube) makes sure the whole area of the evaporator (and condenser) is used.
#109
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1922 Ford Model T / no OBD
Looks like another case of Alzheimer.
Just in reply #95 you were thinking that regarding temperature whole coil is the same.
In reply #106 you said "exactly" to evaporator not holding uniform temperature.
Now you are saying that you did not change your opinion.
You are giving old people bad wrap.
Just in reply #95 you were thinking that regarding temperature whole coil is the same.
In reply #106 you said "exactly" to evaporator not holding uniform temperature.
Now you are saying that you did not change your opinion.
You are giving old people bad wrap.
#110
MBWorld Fanatic!
Looks like another case of Alzheimer.
Just in reply #95 you were thinking that regarding temperature whole coil is the same.
In reply #106 you said "exactly" to evaporator not holding uniform temperature.
Now you are saying that you did not change your opinion.
You are giving old people bad wrap.
Just in reply #95 you were thinking that regarding temperature whole coil is the same.
In reply #106 you said "exactly" to evaporator not holding uniform temperature.
Now you are saying that you did not change your opinion.
You are giving old people bad wrap.
#111
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#112
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1922 Ford Model T / no OBD