A/C compressor quit running!

[jcweller1]

Hey guys and gals!
I just ran into a situation here in south Florida where it is still hot.
My a/c quit. I checked all fuses and all are OK.
I don't see any broken wires. Any thoughts?

 

[lindenengineering]

Get your refrigerant charge level checked first.
The most practical/ expedient method is to get an A/C shop to recover what is in there and then weight the existing against the spec charge of 1.9 lbs.
Then charge to MB spec and retest doing a full performance test.
Dennis
Mechanic

 

[Brian.]

Actually, the FIRST thing to check is if the compressor is coming on (because it's free, fast and everyone can DIY).

When you turn the AC on, while the engine is running, and then go look at the serpentine belt going around the AC pully (bottom pulley on drivers side), the part to the Radiator side should be spinning. If it's not, then the AC clutch is either bad or not getting signal to turn on. My clutch went bad (this item Can be replaced on its own, but it's honestly more work than draining the coolant, changing the compressor/related parts and refilling ~ probably more expensive if you're paying someone to do the work too), which was caused by a failing compressor body that was dragging. Same exact symptoms you've mentioned.

Anyway, there's no reason to think the coolant charge level is low if the AC stopped working suddenly.

Are you a DIYer or needing a shop to do the work?

 

[BenJohnson]

If you sprung an AC leak, pressure switches will cause the AC system to stop working.

 

[One call a/c]

Mine quit last year. The clutch went. Had 12v at the compressor. Check that first.


Sent from my iPhone using Tapatalk

 

[misterbond10]

Actually, the FIRST thing to check is if the compressor is coming on (because it's free, fast and everyone can DIY).

When you turn the AC on, while the engine is running, and then go look at the serpentine belt going around the AC pully (bottom pulley on drivers side), the part to the Radiator side should be spinning. If it's not, then the AC clutch is either bad or not getting signal to turn on. My clutch went bad (this item Can be replaced on its own, but it's honestly more work than draining the coolant, changing the compressor/related parts and refilling ~ probably more expensive if you're paying someone to do the work too), which was caused by a failing compressor body that was dragging. Same exact symptoms you've mentioned.

Anyway, there's no reason to think the coolant charge level is low if the AC stopped working suddenly.

Are you a DIYer or needing a shop to do the work?

You're saying its more work to change a compressor clutch than doing a complete rehab on the A/C system?

 

[Brian.]

Yup, that's EXACTLY what I'm saying. And I'm saying that with 20 years of being paid to turn wrench (motorcycles though, but the point is I'm more than comfortable and competent with a wrench). The problem is ACCESS. If you try to do it without removing anything, you have nearly no access to the recessed circlip. I'm talking such limited access that it's nearly impossible to get the circlip pliers in there to even do the job in the first place. If you try to make it a little easier, remove the power steering pump (access) and AC compressor so you can move it a little, the situation moves from impossible to just really, REALLY frustrating.

The other option is to pull the condenser, radiator and entire front end of the van. so you have direct access to the front of the AC compressor. No clue what that involves (and it may not involve removing everything), but I spent about 6 hours fighting the AC clutch change and 2 hours when I simply replaced the compressor, receiver/dryer, and expansion valve. I spent another ~20 minutes (over the course of about 2 hours, but I was busy with other things most of that time) hooking up the vacuum and refilling the coolant. Half the labor time, parts costs about $100 more. Maybe a dedicated AC shop/mechanic who's willing to do just the clutch/does it frequently and has a system.

Hey, but if you're Gods Gift to mechanics....

 

[jcweller1]

Thanks for all the feedback. My guess is that it could be low on charge. The clutch is not engaging. I did have an issue with dash control unit where the knobs got hard to move and I lubed the cables. The temp knob also
broke so it just spun around. I was able to tear it all apart and hot glue the pieces back together and it all worked fine for about 3 weeks. I got in the van the other day and no a/c......80 degrees in FL....not good.
I'm going to have a local shop gauge the system and see if it is low on coolant. If all is OK then I guess it's diagnosis time.

 

[lindenengineering]

Here's tip!
With the engine running pull off the socket for the binary switch (located on top of the receiver drier) Within a few seconds the condenser cooling fan will activate by itself. This will prove circuit integrity to a great extent.
If the fan doesn't spin then get a long screwdriver or straightened out wire coat hanger and try to spin the CONDENSER fan blades through the grill slots.

These fans are known for seizure which will cause the top pipe head pressure to go very high and can cause a safety valve blow off losing refrigerant to atmosphere in the process.

From experience if the clutch is shot it is expedient these days to replace the compressor if you want fit and forget longevity. These Denso compressors are good but do not come into the same class as the old indestructible long barrel Harrison of Yankee iron era big lung cars fame.

The other quite well known issue is that over time the charge point valves leak and the system gradually loses charge . The high side valve socket is available from MB but the low side is best tackled for leakage eradication by replacing the complete pipe.

DIY A/C repairs can be expensive in the mistakes fraught with problems arena and in any case the T1N van is touchy on charge amounts! So winging it with a can of A/C mix "Yum Yum might get you into more trouble than you would wish for.

One of these days someone is going to legislate that sales of A/C products to non licensed A/C people is a bad idea for you types trying to be a YouTube grad . So for those of you "trying" this type of repair and venting refrigerant to atmosphere carry on and don't panic !--BUT wear safety glasses and a work glove!
Dennis .
EPA Licensed A/C mechanic

 

[jcweller1]

We all! It looks like the heater a/c controller is bad. I have one coming and will let you know what the outcome is.
Have an awesome weekend.

 

[jcweller1]

We all! It looks like the heater a/c controller is bad. I have one coming and will let you know what the outcome is.
Have an awesome weekend.

OK, the part came 3 days early and it works great!! I got the used A/C Heater Control Unit from an Ebay seller and it did the job for a fraction of the price from the dealer or buying new.

 

[outbound]

.....

DIY A/C repairs can be expensive in the mistakes fraught with problems arena and in any case the T1N van is touchy on charge amounts! So winging it with a can of A/C mix "Yum Yum might get you into more trouble than you would wish for.

One of these days someone is going to legislate that sales of A/C products to non licensed A/C people is a bad idea for you types trying to be a YouTube grad . So for those of you "trying" this type of repair and venting refrigerant to atmosphere carry on and don't panic !--BUT wear safety glasses and a work glove!
Dennis .
EPA Licensed A/C mechanic

been done, years ago. (however the 12oz 'miracle in a can' products abound, go figger

and THE ONLY WAY to charge a system is to start with ZILCH (recover whatevers in there first)
if one doesnt KNOW THE HISTORY of said system ?
then, while its empty, CHECK THE OIL (since if the gas is gone, theres an oil leak somewhere as well)

then FIND THE LEAK.
(this is NOT 'optional' its in the EPA rules, but 'small' leaks are... uhhh... 'permissible' ...)
FIX THE LEAK

then EVACUATE the system (using a 'micron gauge' vs just the manifold gauge).

then WEIGH-IN THE CHARGE (and just having been thru my sprinter oil + tranny fluid changeouts, would also say)
USE A GOOD DIGITAL SCALE (that will measure GRAMS or tenths/hundredths of ounces, vs 'pounds')

just from 30yrs

 

[Midwestdrifter]

It is actually possible to get within about 2% of a weighted charge using a calibrated table and temperature probes. Using 2 temperature probes, and a gauge set you can measure the temperature drop of the refrigerant across the condenser, and determine superheat, overcool, and then add refrigerant as needed. Now what often will get you, is if there is non-condensable gasses in the mix. Even 5% total mass of air will totally mess the system up, as it will accumulate in the condenser...

Much easier to just evacuate and measure the charge (at least on a car). On industrial refrigeration equipment (which can have hundreds of lbs of refrigerant), adjusting a charge is often the most expedient approach. Of course those systems often have more extensive documentation than the average car...

On the newest generation of automotive AC systems the variable displacement compressors make it a bit more complicated, especially with the computer control algorithms fiddling with everything.

 

[jcweller1]

These guys did a great job. They pumped the system down to see what it had for a charge and then recharged it. It had 1.4 lbs when it called for 1.9 lbs. I have had the van for about 4-5 years now and never had anything done to the a/c. They leak checked it and said that it looked like the van had never had any a/c service done. No leaks that they could see. If it has one, it has to be small to go down .5 lbs in 12 years. I'm good with that.
Thank you all for the great feedback. I love this forum.

 

[lindenengineering]

These guys did a great job. They pumped the system down to see what it had for a charge and then recharged it. It had 1.4 lbs when it called for 1.9 lbs. I have had the van for about 4-5 years now and never had anything done to the a/c. They leak checked it and said that it looked like the van had never had any a/c service done. No leaks that they could see. If it has one, it has to be small to go down .5 lbs in 12 years. I'm good with that.
Thank you all for the great feedback. I love this forum.

There you are and that wan't too difficult or financially painful was it!
What did they charge you $75?

I often mention this is the best way to check your A/C system, but I can tell many would prefer to buy a can of unverified A/C refrigerate yum yum in a can and try it themselves-----
All the best
Dennis

 

[Dougflas]

The most common AC problem with automotive systems is loss of refrigerant. These newer systems use small amounts of refrigerant and 2 or 3 oz can make a huge difference. TIN Sprinters are known for having ring cracks in the HVAC control head at the relay. Usually, resoldering corrects this problem. Another common problem is a worn clutch. Carefully tapping the clutch front while engine is running will verify this. If the clutch is worn, change the complete compressor. The normal AC shop that pulls an evacuation for 20 to 30 minutes is NOT doing anything as far as boiling moisture. This will take a few hours and the usage of a micron gauge. And always change the drier when the system is opened up.

 

[lindenengineering]

It is actually possible to get within about 2% of a weighted charge using a calibrated table and temperature probes. Using 2 temperature probes, and a gauge set you can measure the temperature drop of the refrigerant across the condenser, and determine superheat, overcool, and then add refrigerant as needed. Now what often will get you, is if there is non-condensable gasses in the mix. Even 5% total mass of air will totally mess the system up, as it will accumulate in the condenser...

Much easier to just evacuate and measure the charge (at least on a car). On industrial refrigeration equipment (which can have hundreds of lbs of refrigerant), adjusting a charge is often the most expedient approach. Of course those systems often have more extensive documentation than the average car...

On the newest generation of automotive AC systems the variable displacement compressors make it a bit more complicated, especially with the computer control algorithms fiddling with everything.

You have hit the nail on the head as to measurement of actual refrigerant in the can if you buy it from an auto parts store as a non licensed A/C Youtube graduate !

So a question when you buy that big gulp can?
How much is refrigerant, how much is oil and how much is sealant residing in that yum yum mixture claiming instant A/C recovery?
Then ask yourself why can they sell a restricted product to the general public?

Might it be that you are buying a majority of oil and some sealant with just enough minimal refrigerant to comply with regulations.
Check the contents on the can!
Before you give that A/C system the big slurpee!
Dennis
Mechanic