AC troubleshooting

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UmmScott

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Dantheman1540 said:
@UmmScott last thing. Do I need to change anything in the rear ac system? I know it's all connected is there anything back there I need to mess with?
Click to expand...
The only thing would be the expansion valve. They normally will fail closed either due to a bad powerhead on the valve or get physically plugged up with debris.

Gotta open up the rear hvac box to get to it.

When you take out the condenser get a flashlight and look inside the open lines and look real carefully. Make sure theyre clean and that there isnt any buildup. Especially black sludgy looking things.
The discharge from the compressor will always have some debris in it but the line leaving the condenser should be clean.

If by some chance the line exiting the condenser and going to the split portion that feeds the front and rear units has debris or gunk in it, then i highly recommend flushing it out while you have the system open. As that could clog up your orifice and the exp valve in the rear.

But if lines look clean and just oily then you're good [emoji106][emoji106]

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Dantheman1540

Dantheman1540

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UmmScott said:
The only thing would be the expansion valve. They normally will fail closed either due to a bad powerhead on the valve or get physically plugged up with debris.

Gotta open up the rear hvac box to get to it.

When you take out the condenser get a flashlight and look inside the open lines and look real carefully. Make sure theyre clean and that there isnt any buildup. Especially black sludgy looking things.
The discharge from the compressor will always have some debris in it but the line leaving the condenser should be clean.

If by some chance the line exiting the condenser and going to the split portion that feeds the front and rear units has debris or gunk in it, then i highly recommend flushing it out while you have the system open. As that could clog up your orifice and the exp valve in the rear.

But if lines look clean and just oily then you're good [emoji106][emoji106]

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Click to expand...

Here is 3 swabs of the line exiting the condenser. Also some pictures of the various ports. Everything looks really clean to me.

Even swabbed the compressor and found nothing but oil. 20200527_204454.jpg 20200527_211234.jpg 20200527_210132.jpg 20200527_210125.jpg 20200527_205746.jpg
 
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Dantheman1540

Dantheman1540

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Should I blow the evaporator out with my compressor? I really don't want to put the dash apart.

Since everything looks clean does that mean it likely wasn't clogged and the compressor wasn't dying?
 
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Dantheman1540

Dantheman1540

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Getting pissed I changed the compressor, condenser, orifice tube and drier cleaned all the lines and evap core which were basically clean besides a little oil. Also added exactly 11oz of oil like it says to.and yet it's doing the same thing. Not even 2 cans 24oz in and it's reading crazy pressures again.

I vacuumed the system for over an hour then let it sit while I ran to town for coolant and lunch and it didn't drop a single psi.

Wtf do I do now?

 
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Dantheman1540

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Well with only the front AC on pressures are normal and the air is cold. Turn rear on and pressures spike. I got 3 and a half cans roughly 43oz in it and it's cold. Need to go for a drive because it's probably close to 120* in my tin can shop right now.

I'm thinking rear expansion valve is clogged. Stand by for updates lol
 
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UmmScott

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Dantheman1540 said:
Well with only the front AC on pressures are normal and the air is cold. Turn rear on and pressures spike. I got 3 and a half cans roughly 43oz in it and it's cold. Need to go for a drive because it's probably close to 120* in my tin can shop right now.

I'm thinking rear expansion valve is clogged. Stand by for updates lol
Click to expand...
No i disagree...
Something else is wrong.

Heres the thing. The rear never shuts off. If the compressor is on, then the rear is on too.
Theres no physically stopping the refrigerant flow to the rear.
The only thing that happens when u turn it off is the blower shuts off.

While i am skeptical of those cans, unless you're seriously overcharging it then that head pressure its very unacceptable.
Is your radiator fan working?? Please double check that.
Also do you have electric or clutch driven fan(s)

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UmmScott

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Another thing...

Did you get the CORRECT condenser?
Again. Parts are specific whether you have front or front and rear AC.
If you got a condenser for a front only AC system that will be a big problem

God i hope thats not the case for ya.

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