AC Compressor issue - Help please

[CWBenjamin]

I just filled the refrigerant, replaced the blend door actuator and ensured the blend doors are working properly...

Pressure is there, but the compressor keeps kicking on and off every 10 seconds. Air is blowing ambient temp as well... Any ideas? TIA

 

[uss2defiant]

really can't troubleshoot AC compressor without ambient temperature, low side and high side pressures.

here's some notes I compiled when I replaced my compressor.
https://www.jeepkj.com/threads/ac-s...nd-refrig-oil-amount-performance-chart.58537/

 

[LibertyTC]

You must be registered for see images attach

http://www.colorado4wheel.com/manuals/Jeep/KJ/2003JeepKJServiceManual.pdf

 

[Billwill]

Should not kick in and out while AC is turned ON...need to check the pressures as above.

With AC switched OFF the AC still does kick in and out by itself..supposed to stop windscreen from fogging up or something...may be model dependant

Some KJ owners have modified the electricals to stop this happening.

 

[CWBenjamin]

I ordered a set of gauges so I will update when I have them and can get some proper readings! Thanks guys

 

[uss2defiant]

you can get a loaner from your local auto parts store

 

[adamkrz]

Was better in the old days when there was a sight glass in the liquid line coming out of the condenser, when the bubbles stop it was full.

Today's ac systems need to be more exact and really need to be charged by someone with proper knowledge, I see a lot of vehicles either overcharged or lots of non-condensables in the system.

After you vacuum the system the charging line has to be purged before allowing refrigerant into the system. I see this often neglected by backyard mechanics..

 

[uss2defiant]

That's very true. Especially with those built in low side gauge only recharge kits. Really need a machine to do the recovery and refill properly.

Even when I installed the hardware, I was able to work with an AC shop to do the diagnostic and refill.

They even found a pin hole leak on the low Side return hose which I didn't find.

So far my AC has been holding up well for the past 4 years since my last repair. Knock on wood.

 

[daves06lrenegade]

Glad to see you bought a set of gauges ,,, Now search the web for some videos on repairing your car's AC system... I see you have a low pressure switch on the accumulator ...Too low refrigerant will cause the On/Off problem you are having... Also many newer cars have a high pressure switch that will cause cycling if too much refrigerant has been put into the system... If you do not have any idea of how much is in the system it may be better to have the system evacuated (pumped to a vacuum) and then reintroduce the R134 into the system... A small digital scale (cheap on ebay) that reads up to a couple of pounds for the 12oz cans can then tell you how much you have put into the system... Read the full can and subtract 12oz from that number...As you fill the system keep track of the ozs you have used... You should have a label on the radiator support or the hood telling you how many ozs/grams your system uses... A vacuum pump can be bought at Harbor Freight for under $100... A valve for the 12 oz cans that will attach to the YELLOW (center) manifold set will allow you to use the gauges and can be bought at your local auto parts store for around $10... With a set of gauges, a vacuum pump, and the can valve you can do a lot of friends/family cars... All these parts and a little learning will save you the full cost of just one visit to the AC shop and you now OWN the tools for future repairs... I added some R1234yf adaptors for my 2016 Chrysler 200s system and have recharged the rebuilt AC system with what AC tools I currently have...

The R1234yf is the ozone friendly chemical equivalent to the older R134a... R1234yf costs much more (aprox 10 times as much)... Manufactures were forced to change to the newer refrigerant in 2016 by the EPA... If anyone decides to use the older than you must flush the system to remove the PAG oil and replace it with a compatible oil for R134a... I checked the part numbers for the AC parts on both the 2015 and the 2016 Chrysler 200 models and the only differences was in the hoses that used the R1234yf connectors... The evaporator/condenser/accumulators were the same... The hoses, refrigerant and PAG oil were the only different... The amount of ozs of refrigerant was also less for the R1234yf than for R134a...

My 2016 Chrysler 200 has been running over a year now with R134a, it;s cold and hasn't had any freeze up problems that were promised by the R1234yf community..

Just some thoughts for anyone reading this post and looking at the changes...
Dave

 

[uss2defiant]

Refrigerant needs to be recovered before evacuated by a vacuum machine.
You'll need a shop to do the recovery.
Against the law to vent large amounts of refrigerant to the atmosphere.

Also you can get a vacuum pump for the rent tool program from your local auto parts store.

 

[CWBenjamin]

Okay fellas, so I ran the gauges and here's the things I've noticed...

The compressor turns off and on every 5 seconds or so when the ac is running... Keep in mind that before I fixed my blend door and actuator, I ran the heater all winter, but it was on cold setting because the actuator was messed up.. So all winter the AC was running while blowing heat.. So there is 1 reason I think it might be my compressor is worn out...

So, my low side pressure goes from 42 ish down to between 10-20 when compressor kicks on and back up when it turns right back off a few seconds later.

My high pressure side is around the same psi (45-50) but goes up to 75 while the compressor is on.

When the vehicle is off, the pressure is at 40 psi on low side, and 45-50 on high side.


My girlfriends SUV is coincidentally having no cold air as well...

Her compressor visibly kicks on with the AC and stays on continuously, but her pressure never goes up and down and stays the same at 40 psi on low side, and 50 ish on the high side, doesn't move at all and stays the same when the car is turned off.

Thinking hers could be the compressor clutch and mine be the entire compressor?

 

[CWBenjamin]

Also, what type of ac compressor would you guys recommend? Is the four seasons from autozone acceptable since they give a lifetime warranty with it? They sell 3 different four seasons compressors that fit my jeep... $150, $220 $360

I was also looking at Denso ac compressors around $200

 

[CWBenjamin]

Glad to see you bought a set of gauges ,,, Now search the web for some videos on repairing your car's AC system... I see you have a low pressure switch on the accumulator ...Too low refrigerant will cause the On/Off problem you are having... Also many newer cars have a high pressure switch that will cause cycling if too much refrigerant has been put into the system... If you do not have any idea of how much is in the system it may be better to have the system evacuated (pumped to a vacuum) and then reintroduce the R134 into the system... A small digital scale (cheap on ebay) that reads up to a couple of pounds for the 12oz cans can then tell you how much you have put into the system... Read the full can and subtract 12oz from that number...As you fill the system keep track of the ozs you have used... You should have a label on the radiator support or the hood telling you how many ozs/grams your system uses... A vacuum pump can be bought at Harbor Freight for under $100... A valve for the 12 oz cans that will attach to the YELLOW (center) manifold set will allow you to use the gauges and can be bought at your local auto parts store for around $10... With a set of gauges, a vacuum pump, and the can valve you can do a lot of friends/family cars... All these parts and a little learning will save you the full cost of just one visit to the AC shop and you now OWN the tools for future repairs... I added some R1234yf adaptors for my 2016 Chrysler 200s system and have recharged the rebuilt AC system with what AC tools I currently have...

The R1234yf is the ozone friendly chemical equivalent to the older R134a... R1234yf costs much more (aprox 10 times as much)... Manufactures were forced to change to the newer refrigerant in 2016 by the EPA... If anyone decides to use the older than you must flush the system to remove the PAG oil and replace it with a compatible oil for R134a... I checked the part numbers for the AC parts on both the 2015 and the 2016 Chrysler 200 models and the only differences was in the hoses that used the R1234yf connectors... The evaporator/condenser/accumulators were the same... The hoses, refrigerant and PAG oil were the only different... The amount of ozs of refrigerant was also less for the R1234yf than for R134a...

My 2016 Chrysler 200 has been running over a year now with R134a, it;s cold and hasn't had any freeze up problems that were promised by the R1234yf community..

Just some thoughts for anyone reading this post and looking at the changes...
Dave

Thank you for all the information. I really appreciate it!

 

[uss2defiant]

mmm I'm not an AC tech so can't help but it sounds like it's low on refrigerant based on the pressures and the compressor engaging and disengaging.

If you do change the compressor, to keep in mind you'll have to change the accumulator and the low side line for the warranty. Also some may require you to flush the system. YMMV

 

[CWBenjamin]

Yeah, I considered low refrigerant, but it got overfilled the last time I was testing it and both sides were still matched at 100 psi...

I ordered basically everything new, accumulator, compressor with clutch, condenser... Figured if I am replacing one might as well do all of them. Ordered pag 46 oil, all new gaskets and o rings, new orifice tube etc...

So I was wondering also, I keep reading about an expansion valve, but I did not see one in my jeeps diagram or parts fiche... Do you know if they have one or not?

 

[CWBenjamin]

I keep hearing people say flush tthe system but I watched a technician talk about how that is old process because the new condensers have such tiny lines through the fins that anything flushed out of the system would certainly clog the condenser, and that it is always better to just buy a new condenser instead of flushing. Just do proper vacuum.

 

[uss2defiant]

Yeah, I considered low refrigerant, but it got overfilled the last time I was testing it and both sides were still matched at 100 psi...

I ordered basically everything new, accumulator, compressor with clutch, condenser... Figured if I am replacing one might as well do all of them. Ordered pag 46 oil, all new gaskets and o rings, new orifice tube etc...

So I was wondering also, I keep reading about an expansion valve, but I did not see one in my jeeps diagram or parts fiche... Do you know if they have one or not?

That's why I recommend working with an A/C shop to do the recovery and refill since they have proper tools for it.

I think there's only the orifice tube in the aluminum low side line so there's no expansion valve.

 

[uss2defiant]

I keep hearing people say flush tthe system but I watched a technician talk about how that is old process because the new condensers have such tiny lines through the fins that anything flushed out of the system would certainly clog the condenser, and that it is always better to just buy a new condenser instead of flushing. Just do proper vacuum.

That's true but I'd do what you need to maintain your compressor's warranty.
I believe OEM compressor is Denso.

 

[CWBenjamin]

Sweet, I ordered denso compressor and condenser.

 

[daves06lrenegade]

As uss2defiant said there is no expansion valve.

That function is handled by a "fixed orifice device" located within the aluminum low side line... Both devices are used within the automotive industry... In a R134a system the system requires that a vacuum be pulled... If you don't evacuate the system the oxygen left in the system will combine with the R134a and create an acid that can/will damage the system over time... Seeing that you are replacing both the compressor and condenser I would also suggest that you replace the orifice device... It takes such a small particle to block it and make the system fail...
Dave

https://www.ebay.com/itm/New-AC-A-C...983734&hash=item3cd1ed075b:g:qOcAAMXQhpdRnp~E