AC compressor keeps cycling every 5 secs

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Najeem
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Re: AC compressor keeps cycling every 5 secs

Post by Najeem »

tbirdtbird wrote: Sat May 21, 2022 10:56 am It seems we are getting somewhere.
That last set of pressures, what were the operating conditions?
RPM
Doors open
Fan Max
Temp setting Max cool
is what it should be.
Also, same ambient as you mentioned, ie 87 degrees?

This thread has gone on so much I do not recall if it was suggested that you had a leak?
After all, you did have to add one can of 1234YF
Doors closed with Max AC and RPM was about 800 at idle. Only difference was today temp was 87F as opposed to 74F on the previous attempt. I also added one 8oz 1234 can on the previous attempt but the outside temp was low and compressor kept short cycling every 10secs so was useless. I think the bodyshop that repaired my car didn't fully charge it maybe?
tbirdtbird
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Re: AC compressor keeps cycling every 5 secs

Post by tbirdtbird »

Najeem wrote: Sat May 21, 2022 11:55 am
tbirdtbird wrote: Sat May 21, 2022 10:56 am It seems we are getting somewhere.
That last set of pressures, what were the operating conditions?
RPM
Doors open
Fan Max
Temp setting Max cool
is what it should be.
Also, same ambient as you mentioned, ie 87 degrees?

This thread has gone on so much I do not recall if it was suggested that you had a leak?
After all, you did have to add one can of 1234YF
Doors closed with Max AC and RPM was about 800 at idle. Only difference was today temp was 87F as opposed to 74F on the previous attempt. I also added one 8oz 1234 can on the previous attempt but the outside temp was low and compressor kept short cycling every 10secs so was useless. I think the bodyshop that repaired my car didn't fully charge it maybe?
Your testing would be waay more meaningful if you observed the test conditions referenced above.RPM should be 1500. Sry, I left that number off my post. These are standardized testing parameters used by the pros for any car. The 1500 RPM is to enable the comp to actually do something. They don't pump much at idle or 800 RPM.
Is this the first we have learned of a collision repair?...
They may have undercharged it as a way to save money!!!!
When considering your next auto A/C purchase, please consider the site that supports you: www.ACKits.com
Najeem
Posts: 16
Joined: Thu May 05, 2022 8:58 am

Re: AC compressor keeps cycling every 5 secs

Post by Najeem »

tbirdtbird wrote: Sat May 21, 2022 12:14 pm
Najeem wrote: Sat May 21, 2022 11:55 am
tbirdtbird wrote: Sat May 21, 2022 10:56 am It seems we are getting somewhere.
That last set of pressures, what were the operating conditions?
RPM
Doors open
Fan Max
Temp setting Max cool
is what it should be.
Also, same ambient as you mentioned, ie 87 degrees?

This thread has gone on so much I do not recall if it was suggested that you had a leak?
After all, you did have to add one can of 1234YF
Doors closed with Max AC and RPM was about 800 at idle. Only difference was today temp was 87F as opposed to 74F on the previous attempt. I also added one 8oz 1234 can on the previous attempt but the outside temp was low and compressor kept short cycling every 10secs so was useless. I think the bodyshop that repaired my car didn't fully charge it maybe?
Your testing would be waay more meaningful if you observed the test conditions referenced above.RPM should be 1500. Sry, I left that number off my post. These are standardized testing parameters used by the pros for any car. The 1500 RPM is to enable the comp to actually do something. They don't pump much at idle or 800 RPM.
Is this the first we have learned of a collision repair?...
They may have undercharged it as a way to save money!!!!
I will check rpm again. I had all of those settings just the doors were closed. I also did mention left side front end collision to another user and I have a strong feeling they short changed me. All of my issues started after the repair to the left side of the car
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JohnHere
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Re: AC compressor keeps cycling every 5 secs

Post by JohnHere »

Najeem wrote: Sat May 21, 2022 1:06 pm I also did mention left side front end collision to another user and I have a strong feeling they short changed me. All of my issues started after the repair to the left side of the car
I think you mentioned front-end collision damage after I asked but not specifically to the left side. Regradless, carefully examine the front left side internally for damage, however slight, to any components related to the A/C system. Also scrutinize the condenser, which mounts in front of the radiator.
Member – MACS (Mobile Air Climate Systems Association)

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tbirdtbird
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Re: AC compressor keeps cycling every 5 secs

Post by tbirdtbird »

OK, it has been quite a lengthy thread and you lose track. I went back and reviewed all posts. Yes, the collision was noted on the first page, but there was uncertainty as to what was replaced. Might not be a bad idea to look at the repair bill to see what was itemized, so that you can keep an eye on those areas. I think you said maybe some lines/hoses. Unsure of condenser.

Might be time to get an electronic sniffer, since you are doing a lot of the work yourself, it will prove invaluable over time
When considering your next auto A/C purchase, please consider the site that supports you: www.ACKits.com
Najeem
Posts: 16
Joined: Thu May 05, 2022 8:58 am

Re: AC compressor keeps cycling every 5 secs

Post by Najeem »

tbirdtbird wrote: Sat May 21, 2022 3:01 pm OK, it has been quite a lengthy thread and you lose track. I went back and reviewed all posts. Yes, the collision was noted on the first page, but there was uncertainty as to what was replaced. Might not be a bad idea to look at the repair bill to see what was itemized, so that you can keep an eye on those areas. I think you said maybe some lines/hoses. Unsure of condenser.

Might be time to get an electronic sniffer, since you are doing a lot of the work yourself, it will prove invaluable over time
Yes, I’ll probably get that device and take a look. I followed the ac lines closely but didn’t see anything strange but I guess the sniffer is my best bet. Funny part is the car isn't short cycling anymore and today is the first day outside temp was above 80F
Last edited by Najeem on Sat May 21, 2022 4:10 pm, edited 1 time in total.
tbirdtbird
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Re: AC compressor keeps cycling every 5 secs

Post by tbirdtbird »

maybe the one can did the trick
I think some of your earlier short cycling was due to low ambient (there is not very much work for a comp at low ambient, so it is not gonna stay on long at all)

Does this Durango have rear air?
When considering your next auto A/C purchase, please consider the site that supports you: www.ACKits.com
Najeem
Posts: 16
Joined: Thu May 05, 2022 8:58 am

Re: AC compressor keeps cycling every 5 secs

Post by Najeem »

tbirdtbird wrote: Sat May 21, 2022 3:58 pm maybe the one can did the trick
I think some of your earlier short cycling was due to low ambient (there is not very much work for a comp at low ambient, so it is not gonna stay on long at all)

Does this Durango have rear air?
Thank you for the info. Yes, it has rear air
Najeem
Posts: 16
Joined: Thu May 05, 2022 8:58 am

Re: AC compressor keeps cycling every 5 secs

Post by Najeem »

So, today outside temp was 90-95F and I noticed the car only short cycles when the fan speed is on med-low setting now. Then when I hit the max fan speed it stops short cycling.
RPM stays the same at 800
Doors Open

Low-Med Fan speed (Max AC, Lowest Temp, Low-Med Fan Speed)
https://www.dropbox.com/s/5hjtv88zes3zr ... M.mov?dl=0

Max Fan speed (Max AC, Lowest Temp, Max Fan Speed)
https://www.dropbox.com/s/yxcik6fm1456z ... M.mov?dl=0
tbirdtbird
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Re: AC compressor keeps cycling every 5 secs

Post by tbirdtbird »

Najeem wrote: Sun May 22, 2022 11:30 am So, today outside temp was 90-95F and I noticed the car only short cycles when the fan speed is on med-low setting now. Then when I hit the max fan speed it stops short cycling.
RPM stays the same at 800
Doors Open
I am seeing about 36 low and nearly 200 high. Those number don't look bad, and the ambient is at a good temp to give a good test, BUT you did not state what the center vent temp is! And a ray-gun type IR thermometer is not the most accurate way to get that temp because of reflectivity issues.
ALSO, I think we have a miscommunication. YOU are the one who must bring the car up to 1500 RPM, a common way to do this is to have a helper inside the car depress the gas pedal enough to get 1500 on the tach.
The engine is not going to magically work its way up to 1500 from 800.
And John has wondered if your blend doors are not entirely shutting off the heat function, thus blending in some heated air to your cooler air. This could account for why your cooling is not as good as it was. He made a very good point, and we suggest that you check that.

Let's try this again. This is the way to perform a maximum load test
1. You set engine RPM to 1500 [the comp is barely doing any work at 800 RPM and such numbers have no meaning]
2. Doors open
3. Set AC to max fan and max cool
4. Recirculate ON
5. state ambient
6. state the center vent temp
7. Record hi and low pressures when the compressor cycles ON.
8. a vid is optional

This info would constitute a valid data point.
When considering your next auto A/C purchase, please consider the site that supports you: www.ACKits.com
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