New AC condenser, which port do I vacuum before charging?

I wish I knew, seems like someone would have the correct answe on here.

 

For this I'd strongly recommend referring to your manual on techinfo.toyota.com. It is likely to have important information like how to calculate the oil amount on a partial replacement, and the right way to perform the evacuate and recharge and to determine when you have charged the correct amount. (For Gen 1 the proper charge is a certain number of grams of refrigerant past where the sight glass bubbles disappear, your details may be different, you don't want to get this wrong.)

Cheers,
-Chap

 

Pay the $15 for a two business day subscription to get the factory service manual; a ton of info.

You need to use a NEW AC Manifold gauge set for the Prius. This is to ensure no contaminants (PAG oil) enters the system. This gauge will now be your dedicated Toyota Hy rid AC Manifold gauge.

A new vaccum pump might be best to further eliminate any possibiluty of introduci g contaminents (PAG oil).

Freon gas 134a is the modern car standard. ND-11 electric compressor oil is specific to Toyota Hybrids.

Maybe just let a Toy dealer evacuate and recharge? The dealers in my area charge $150. Yours would probably be a little bit more since your are completely empty.

 

You use both the H and L ports when vacuuming. The factory repair manual assumes you know how to connect the vacuum pump through the manifold gauges to the air conditioning system. Since you asked the question, this website provides a reasonable procedure:
Air Conditioning FAQ

When filling refrigerant, it definitely is introduced into the low pressure port. You can cause a serious accident if the refrigerant can is connected to the high pressure side and explodes.

As the other respondents suggested, you need to subscribe to techinfo.toyota.com so that, among other things, you will know what low and high pressures are acceptable before you declare victory with this project.

 

It's all right tor use the vacuum pump, since it will NOT be used to inject refrigerant into the car's system.

You do, however, need a dedicated manifold gauge set. You probably need another can of R134a.

You vacuum and charge from the center connection of the manifold gauge set. This hose is usually yellow.


The blue hose is connected to the LOW side which is the larger diameter line from the evaporator under the dash that goes through the accumulator to the compressor intake. This is also the line to which you want to add refrigerant.

The RED hose is connected to the high pressure output line. This is the smaller diameter line. While it is fine to vaccum out this line with the high pressure valve on the gauge only, NEVER leave the valve open when the compressurre is running. This could cause a backfeed to the can and cuaise it to explode.

Charge to the BLUE line with the can in the VAPOR mode only. That is, with the can's valve UP. NEVER charge into the compressure in the liquid mode with the can upside down. THIS WILL PUT LIQUID into the compressor input. LIQUID is NOT comresssible and WILL damage the compressor.

GOOD luck.

 

The 2G spec for R-134a refrigerant is 15.9 ounces +/- 1.1 ounce. Yet another reason the OP needs to have the factory repair manual available before he starts this project.

 

That's efficient. Most everyhing I've worked on takes 2-3 pounds.

I do them by temperature and pressure rather than volume.

 

I like the comment to hand over to dealership for charging, all things considered.

 

Is the AC compressor even running? If yes then it sounds like the compressor is damaged or you have a serious leak problem.

 

Sorry, I thought you were trying to charge the air conditioner with refrigerant. No, the AC definitely should be off when the vacuum pump is running. Is the low side pressure gauge showing a vacuum?

I think the pump will need to run at least 30 minutes if not longer. After the pump is stopped, make sure the vacuum holds per the gauge - if it does not then your system has a leak.