Compressor Slugging

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

JExpedition07

That One Member
Joined
Mar 30, 2017
Posts
6,530
Reaction score
3,140
Location
New York
I’ve noticed recently on first startup after a hot shut down my compressor makes noise on startup and is “slugging” because liquid refrigerant is accumulating in the compressor.... from what I understand the new one I put in is now destroyed because of this and it’s time to replace the system again....lasted about a month. my only question is how do I prevent this on the 3rd compressor? Charge was weighed in and pressures were correct when running.
 

gixer2000

Retrofit or Bust
Joined
Oct 13, 2015
Posts
1,467
Reaction score
644
Location
Massachusetts
Refrigerant migration is a tough thing to deal with when the compressor is mounted at the bottom of the engine. Refrigerant migrates to the coldest place and when the interior reaches a high it moves to the compressor. The only thing I could recommend is to warm the engine up before starting the ac.
 
OP
OP
JExpedition07

JExpedition07

That One Member
Joined
Mar 30, 2017
Posts
6,530
Reaction score
3,140
Location
New York
Refrigerant migration is a tough thing to deal with when the compressor is mounted at the bottom of the engine. Refrigerant migrates to the coldest place and when the interior reaches a high it moves to the compressor. The only thing I could recommend is to warm the engine up before starting the ac.

Now I’m wondering how long it’s been doing this as I just started paying attention....the new compressor still seems to be working fine so I’ll try that. Hopefully it’s not too late.
 

gixer2000

Retrofit or Bust
Joined
Oct 13, 2015
Posts
1,467
Reaction score
644
Location
Massachusetts
The accumulator should be boiling off the liquid going back to the compressor but doesn't do much when the system isn't running. Slugging is a very common thing in GM cars and Ford may have some programming to deal with how the compressor starts on a fresh startup. I'll do some research for ya and see what I can find
 
OP
OP
JExpedition07

JExpedition07

That One Member
Joined
Mar 30, 2017
Posts
6,530
Reaction score
3,140
Location
New York
The accumulator should be boiling off the liquid going back to the compressor but doesn't do much when the system isn't running. Slugging is a very common thing in GM cars and Ford may have some programming to deal with how the compressor starts on a fresh startup. I'll do some research for ya and see what I can find

Thanks gixer. My next question is, assuming it’s been doing this since the install should I plan to replace the compressor or not? Through research some say it certainly needs replacing and some say not so much.
 

gixer2000

Retrofit or Bust
Joined
Oct 13, 2015
Posts
1,467
Reaction score
644
Location
Massachusetts
Check this out J. Ive never noticed a slugging issue on my 07 so I suspect something is up like maybe too much oil in your lines causing your issue. So I would have a look at this.

http://www.4s.com/en/marketing/psp-solutions/the-deslugger/

These are like $45 on Amazon/eBay so I would give it a go unless you want to attempt to flush your entire system to get out any excess oil. Chances are oil is your issue
 
Last edited:

gixer2000

Retrofit or Bust
Joined
Oct 13, 2015
Posts
1,467
Reaction score
644
Location
Massachusetts
Thanks gixer. My next question is, assuming it’s been doing this since the install should I plan to replace the compressor or not? Through research some say it certainly needs replacing and some say not so much.
If the compressor is still performing as it should I wouldn't touch it. Its possible internal damage has been done but it will always show a decrease in performance so if it works as it should then leave it be. Now if you get close to the warranty ending on the compressor I personally would swap it just because my luck stinks and it woild go south the day after expiration
 
OP
OP
JExpedition07

JExpedition07

That One Member
Joined
Mar 30, 2017
Posts
6,530
Reaction score
3,140
Location
New York
If the compressor is still performing as it should I wouldn't touch it. Its possible internal damage has been done but it will always show a decrease in performance so if it works as it should then leave it be. Now if you get close to the warranty ending on the compressor I personally would swap it just because my luck stinks and it woild go south the day after expiration

Still works well. This control you linked seems to be a good soloution. It came with a 2yr warranty so I’ll play it by ear, if I have to I’ll swap out later.
 
Last edited:
OP
OP
JExpedition07

JExpedition07

That One Member
Joined
Mar 30, 2017
Posts
6,530
Reaction score
3,140
Location
New York
This morning I let the truck run for 5 minutes before I started the air. No noise and started smooth so I guess it does the trick getting the area warm. The compressor and drier both came with a 24 month warranty so I may take your advice and swap them just before the warranty is up...I think that control is the ticket gixer thanks for the help. Talked to my dad who did refrigeration about it this morning and like you he said to leave the compressor in for now. He said the valves in the compressor will take a lot of abuse before they go and this ones only a little over a month old. Said for now to just stop the slugging from occurring and go from there.
 
Last edited:

99WhiteC5Coupe

Full Access Members
Joined
Jun 3, 2015
Posts
3,403
Reaction score
1,990
Location
USA
I’ve noticed recently on first startup after a hot shut down my compressor makes noise on startup and is “slugging” because liquid refrigerant is accumulating in the compressor.... from what I understand the new one I put in is now destroyed because of this and it’s time to replace the system again....lasted about a month. my only question is how do I prevent this on the 3rd compressor? Charge was weighed in and pressures were correct when running.


I have a 2015 Ford Expedition Limited 4 x 4 - purchased new and never wrecked or damaged. 45,*** miles. The a/c system has never been serviced or opened.

Since about 40,*** miles - if the vehicle is parked for 1-2 days, when I start the engine cold (inside the cabin or using remote start), the engine will start - then in about 1 second, the a/c compressor solenoid clicks and there is an immediate loud “thump”, followed by a brief serpentine belt squeal. This will not occur on hot restart, or if the vehicle is parked 1 day or less. The ambient air is hot, as the vehicle commands a/c startup.

I made an appointment at my Ford dealer and used night drop off. I left a detailed note on when the noise occurs. The dealer was unable to duplicate the problem and it still occurs if the vehicle is parked 1-2 days (rarely parked longer).

I have the Ford premium extended service plan, but I’m frustrated with the lack of repair by the dealer. The service advisor told me not to worry, as I have quite some time and mileage left on the plan.

The noise sounds like the problem you’re having.

Anyone have any ideas? Thank you.
 
OP
OP
JExpedition07

JExpedition07

That One Member
Joined
Mar 30, 2017
Posts
6,530
Reaction score
3,140
Location
New York
I have a 2015 Ford Expedition Limited 4 x 4 - purchased new and never wrecked or damaged. 45,*** miles. The a/c system has never been serviced or opened.

Since about 40,*** miles - if the vehicle is parked for 1-2 days, when I start the engine cold (inside the cabin or using remote start), the engine will start - then in about 1 second, the a/c compressor solenoid clicks and there is an immediate loud “thump”, followed by a brief serpentine belt squeal. This will not occur on hot restart, or if the vehicle is parked 1 day or less. The ambient air is hot, as the vehicle commands a/c startup.

I made an appointment at my Ford dealer and used night drop off. I left a detailed note on when the noise occurs. The dealer was unable to duplicate the problem and it still occurs if the vehicle is parked 1-2 days (rarely parked longer).

I have the Ford premium extended service plan, but I’m frustrated with the lack of repair by the dealer. The service advisor told me not to worry, as I have quite some time and mileage left on the plan.

The noise sounds like the problem you’re having.

Anyone have any ideas? Thank you.

Sounds like the same issue
 
Last edited:
OP
OP
JExpedition07

JExpedition07

That One Member
Joined
Mar 30, 2017
Posts
6,530
Reaction score
3,140
Location
New York
Where is the compressor mounted on the 3.5L? On the 5.4L it’s bottom left of motor.
 

99WhiteC5Coupe

Full Access Members
Joined
Jun 3, 2015
Posts
3,403
Reaction score
1,990
Location
USA
The a/c compressor is at the bottom also. When I remote start the vehicle as I am walking towards it, the loud “thump” sound seems to be coming from the right side of the engine compartment.
 
OP
OP
JExpedition07

JExpedition07

That One Member
Joined
Mar 30, 2017
Posts
6,530
Reaction score
3,140
Location
New York
I’ve been warming up the engine before I click the A/C on and it hasn’t happened since.
 

gixer2000

Retrofit or Bust
Joined
Oct 13, 2015
Posts
1,467
Reaction score
644
Location
Massachusetts
I’ve been warming up the engine before I click the A/C on and it hasn’t happened since.
Thats why so much of the AC equipment I work on comes with factory crank case heaters. Slugging is a bad thing and keeping the compressor warm will keep the liquid out. Glad to see that is working for ya and in interested to see how it goes if you get the deslugger in
 
Last edited:

1955moose

Full Access Members
Joined
Nov 23, 2014
Posts
6,004
Reaction score
1,351
Deslugger, wasn't that Joe DiMaggios pet name in the 50's? At least in Brooklyn it wad!

Sent from my N9131 using Tapatalk
 

gixer2000

Retrofit or Bust
Joined
Oct 13, 2015
Posts
1,467
Reaction score
644
Location
Massachusetts
According to the video on this web site, it is oil, not liquid refrigerant in the compressor.

I said oil but refrigerant migrates to the coldest place. On a hot day the interior temp where the evap lives gets at least 20-30° hotter than ambient thus leaving the compressor I a good place for migration. So while I said oil it very well could be refrigerant also

Either way the deslugger will do what he needs it to do
 
Last edited:
Top