What is the "Air Damper" in A/C system for?

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songzunhuang
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What is the "Air Damper" in A/C system for?

Post by songzunhuang »

As I inspect and gather parts for my A/C overhaul this summer, I came across this air damper and was wondering what it is for. So the replacement Sanden compressor I have has 2 visible connected hoses. As I was inspecting my stock compressor, I noticed that in addition to the 2 hoses connected to the compressor, there is a third hose connected to a cylindrical thing that appears to be mounted to the compressor.

From looking at Real-OEM, I think it is the part #1 below.
What is this "Air Damper" #1 for?
What is this "Air Damper" #1 for?
Screen Shot 2017-04-08 at 6.17.50 PM.png (375.71 KiB) Viewed 6531 times
Can someone explain what this does? Will this be another hose I will have to have made as I change over from R12 to R134a? It appears to be part of the A/C system. Thanks for any insight.
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1984 633CSi
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Re: What is the "Air Damper" in A/C system for?

Post by dwcains »

Not present on my car, and the applicable realoem page says "ONLY APP.TO OSCILLATING PLATE COMPRESSOR". So, forget you ever saw it, and carry on.
Dean
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Re: What is the "Air Damper" in A/C system for?

Post by 86_6series »

It's a muffler to quiet the system from high pressure vibration.
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Re: What is the "Air Damper" in A/C system for?

Post by songzunhuang »

dwcains wrote:Not present on my car, and the applicable realoem page says "ONLY APP.TO OSCILLATING PLATE COMPRESSOR". So, forget you ever saw it, and carry on.
OK, but it is present on my car and when I remove the old compressor, I'll be left with 3 hose ends and only two places on the new compressor to fasten hoses. So what am I to do with the one loose hose?

I'll have to get under there and poke about I guess.
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Song Huang
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Re: What is the "Air Damper" in A/C system for?

Post by songzunhuang »

86_6series wrote:It's a muffler to quiet the system from high pressure vibration.
So if I replace the OEM compressor with a Sanden type, what can I do with this part? Take it off?
Then what about the one open hose end that is left?
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Re: What is the "Air Damper" in A/C system for?

Post by dwcains »

Does your compressor have 3 ports on it? I'm not sure, from that diagram, where the damper is spliced into the system. With the Sanden compressor you'll have one hose pulling refrigerant from the dryer (low side), and the other pumping refrigerant to the condensor (high side).
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Re: What is the "Air Damper" in A/C system for?

Post by 86_6series »

Here's a generic explanation on AC mufflers.

http://www.henrytech.co.uk/wp-content/u ... FFLERS.pdf

I would think the muffler would be inline with the system, not have a line that dead ends into the muffler.

My US 86, as far as I can tell has no muffler
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Re: What is the "Air Damper" in A/C system for?

Post by songzunhuang »

86_6series wrote:Here's a generic explanation on AC mufflers.

http://www.henrytech.co.uk/wp-content/u ... FFLERS.pdf

I would think the muffler would be inline with the system, not have a line that dead ends into the muffler.

My US 86, as far as I can tell has no muffler
Thanks for this. It gives me a good idea of the function. I'm guessing I can delete this when I replace my compressor. I will have to figure out the routing because my OEM compressor has 2 lines going to it already on the topside and this damper is mounted on the bottom with another hose going to it. I'll have to study the routing more closely. It's hard to tell when all the lines go when I look from above with the hood open.
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Re: What is the "Air Damper" in A/C system for?

Post by jacko »

My '89 didn't have one but my Sanden compressor works fine without it.
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Re: What is the "Air Damper" in A/C system for?

Post by songzunhuang »

jacko wrote:My '89 didn't have one but my Sanden compressor works fine without it.
Thanks for the input. It looks like when I changeout my system, the damper is definitely on the "delete" list. I'm guessing that I'll have to also delete the hose going to it and re-route something. I'm just not sure what at this time.
I'll do this in several stages because I'll have to custom build hoses and the condenser mounting points, etc. as I go. Then I'm planning to take out the evaporator core and clean it while also changing the expansion valve. So, lots to do. Meanwhile, I'm going to see if I can still use the car as a daily driver during all this. It'll be interesting.
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