A/C manifold gauge set contaminated?

"#8: A straight-forward approach to avoid cross-contamination is to use dedicated
hoses and injectors for each type of refrigerant oil."

I think that says it all.....

What is the cost of guages and hoses compaired to a new expensive compressor?
And the time and money to properly flush and clean the hoses, expansion valve, receiver/dryer,
evaporator, and condensor?????

 

First issue I believe is that R134a and R1234yf systems have different connectors so you will need to buy an adapter to use your current R134a gauges.

The fancy Snap-On machine has 2 sets of gauges and a seperate set of hoses for each system: Loading...
Other machines with shared gauges and hoses will have a deep purge / cleaning cycle when switching between refrigerants. Its mentioned in the Manual for this one for example: AIRTEK New Fully Automatic R-134A & 1234YF Recovery & Recharge DUAL AC – airtekproducts

Do you know if the freon you added to your Corolla was pure R134a or was it one of those "stop leak" type that may have other stuff mixed in?

If you don't want to get a whole set of gauges, they also make the quick top-off cans with built-in gauge: https://www.autozone.com/a-c-charging-and-refrigerant/r1234yf-refrigerant/p/weitron-r1234yf-refrigerant-can-incudes-diy-charging-kit-and-analog-gauge-11oz/1354076_0_0


EDIT: Ignore what I said about the R1234yf, it looks like our Gen 3 Prius still uses R-134a but with different oil ND-11 instead.

 

Your gauge set isn't going to have any kind of residual that you can measure like you're measuring here You could purge the gauge set if you really thought that was something you needed to do and then that pretty much ends that just run some 134 through it back into your reclaim machine if you do that sort of thing and that's it You're not going to have enough vapor of the improper oil to cause the air conditioning system in any of the Prius to prematurely deteriorate highly unlikely The system will break and be destroyed the car will be in the junkyard probably before that happens or the evaporator will go bad and you need to take apart your whole car.

 

Ignore what I said about the R1234yf in my previous post, it looks like our Gen 3 Prius still uses R-134a but with different oil ND-11 instead.

Also here is an interesting note from the Repair Manual:

• Avoid using the gauge manifold set that had been used for vehicles with conventional compressor oil (ND-OIL8 or equivalent) as much as possible. This will cause compressor oil remaining in the manifold to enter the vehicle, resulting in insulation performance deterioration. A gauge manifold set that had been used 3 times or less can be reused if an appropriate one is not available.

Some more scary warnings from the Repair Manual if you want:


Title: HEATING / AIR CONDITIONING: AIR CONDITIONING SYSTEM: P0AA6-611; Hybrid Battery Voltage System Isolation Fault; 2015 MY Prius [08/2014 - ]

DESCRIPTION
The DTC is stored if there is insulation trouble with the high-voltage circuits in the air conditioning system. Possible causes are poor insulation in the compressor with motor assembly, or mixing of any oil other than ND-OIL 11 in the refrigerant cycle.

The motor driven with high-voltage is built into the electrical compressor and is cooled directly with refrigerant. Compressor oil (ND-OIL 11) with high insulation performance is used because a leakage of electrical power may occur if regular compressor oil (ND-OIL 8) is used.

CAUTION:

• Wear insulated gloves and pull out the service plug grip before inspection as procedures may require disconnecting high-voltage connectors.
• Be sure to carry the removed service plug grip because other workers may install it by mistake.
• Do not touch the high-voltage connectors or terminals for 10 minutes after the service plug grip is removed.

DTC No.: P0AA6-611
DTC Detection Condition: High voltage system insulation malfunction
Trouble Area:

• Compressor oil
• Refrigerant pipe line
• Compressor with motor assembly
• CAN communication system

INSPECTION PROCEDURE
CAUTION:

• Wear insulated gloves and pull out the service plug grip before inspection as procedures may require disconnecting high-voltage connectors.
• Be sure to carry the removed service plug grip because other workers may install it by mistake.
• Do not touch the high-voltage connectors or terminals for 10 minutes after the service plug grip is removed.

NOTICE:

• Electrical insulation performance may decrease significantly if even a small amount of oil other than ND-OIL 11 is used (or enters) in the refrigerant cycle, causing the DTC to be output.
• If other oil is accidentally used and a DTC is output, collect the oil in the refrigerant cycle into the compressor and replace it with ND-OIL 11 to increase the ND-OIL 11 ratio amount.
• Replace the main components (evaporator, condenser, and compressor) if a large amount of oil other than ND-OIL 11 enters the system. Failing to do so may cause electrical insulation performance to remain low, causing the DTC to be output.
• The hybrid control system and air conditioning system output DTCs separately. Inspect DTCs following the flow chart for the hybrid control system first if any DTCs from those systems are output simultaneously.

HINT:
If it can be confirmed that any compressor oil other than ND-OIL 11 has been used in the vehicle, replace the air conditioning cycle.

 

I sprayed some brake cleaner through the hoses to flush them out