Help charging AC

It takes R134a. It can be recharged. There are low-side and high-side service ports and a sight glass. There are specific instructions in the service manual for how to get the correct charge in - if I remember right, the correct charge is not exactly at the point you would think from watching the sight glass. The manual has a detailed procedure for getting it right.

At techinfo.toyota.com you can view the manual as much as you need for two days for $15 which should be plenty for what you need. (Some people have used their two-day window to just download every section and get the whole manual that way; it can also be bought in regular bound form which is more money but less work. It is very helpful if you plan to be doing work on your Prius.)

Whatever you do, don't mistake the fuel-system evap test port for an A/C charge port.

-Chap

 

Charging the AC system is too easy to need the manual. Go to your local parts store, buy a can of R134 and a hose w/ a gauge on it (about $35 total). Here's one I found at Advanced Auto Parts online (Interdynamics EZ Chill R-134a Refrigerant Plus Oil with Leak Sealer (18 oz.) $32.99)

It appears to come w/ a hose and gauge.
The below instructions are condensed. The can comes with more detailed instructions. PLS READ THEM!!!!!!

Locate the "low pressure" fitting on the AC system (cap will have an "L" on top). Hook up the hose, start the car, turn the AC on Max, open the valve on the Refrigerant can and recharge to the "green" area on the gauge. Close the valve, disconnect hose, get in your car and enjoy.

 

If the Prius gen1 aircon pump is driven by the engine that is fine but if like the gen2 and gen3 it is an electric pump on no account put the EZ Chill into the system as it has the wrong oil in it that will ruin the whole system. EZ has PAG oil and for the Prius with electric pumps ND11oil is required.

 

http://www.autoshop101.com/forms/Hybrid06.pdf

Reference above states electric A/C compressor is on 04 and newer.

'01 -'03 compressor as stated in above link is a scroll compressor with an oil separator that reduces the amount of oil circulating in the system.

At the minimum, I would buy pressure gauges before adding refrigerant to any A/C system. Guessing here seems possibly dangerous.

 

Ok, I had time to look in the manual, which is also easy. Your correct charge is: an extra 100 grams of refrigerant, plus or minus 50, past the point where the sight-glass bubbles disappear, under these conditions:

• engine maintaining 1500 rpm (use the service mode?)
• blower on HI
• Max A/C, Recirc ON
• All doors fully open

Because pressures are so closely linked to temperature and operating conditions, just relying on the green area on some can's pressure gauge might not get you very close. You'll get cool air, sure, but for the system to work most effectively requires pretty close to the correct charge.

While charging through the low-side port, be sure you hold your can upright and drawing off the top (vapor only); if you let any liquid slug into the low side, your project cost might go up by the price of a compressor.

-Chap

 

Hey Chap,
Appreciate your posts and you always having my back. Thanks for the details and research.

 

In Sweden we cant buy "top off jars", we must visit a certified cooling dude and spend 200$

But, it works fine with propane, isopropane is ok and butane is no good.
I used small burner bottle about 200g, and keep adding until compressor runs all the time (it stops at low pressure), then a few seconds more. Keeps my Jeep cool.

Seems like that gas is thicker then r-134, because when I payed 200$ it only last 1 week, but this 3-4$ solution lasts for months...

Use at own risk, but gasoline is kind of flammable to so I feel safe any way

 

Another advantage is, should the leak get any bigger, you've got an easy way to find it.

On a serious note, in the US anyway, there would be a disadvantage down the road if you ever need further A/C service requiring disassembly (or even just decide the time has come to fix the leak). Service shops are required to draw out and reclaim the refrigerant, and they incur high costs if their reclamation equipment gets contaminated by mixed refrigerants. They will not generously absorb those costs.

-Chap

 

Check out plumbing supply merchants. Plumbers use a freezer spray to freeze pipes that they cannot drain, this just happens to be R134A the correct coolant for your Prius, also on the same theme electrical cooling spray "used for cooling temperature sensitive components" is also the same product.

I am about to do a write up on the gen2 care and maintenance page this week end showing what to use and how.

 

We have freeze spray here to with r-134. But it's getting hard to find, the new cans use butane gas(! great when using near flame... ) but connector (just like a 5-56 can) is hard to fit to my car adapter, I like to see how that is solved.

 

Yea! I and other a/c repair shops love this stuff being sold to DIY's and low end auto so called repair shop. Many times it works at first unless someone really mess up. The customer is sometimes happy the so called repair shop is happy it collects fast CASH , but later if it had the wrong oil or too much oil and and leak sealer + performance enhancer and throw in some dye. The customer will pay a higher repair bill later and the TECH may misdiagnosis the A/C and replace wrong parts because the customer did not tell the Shop they installed leak stop, more oil and wrong oil, cooling enhancer, carefuller what you wish for you just may get it!.
Only use pure R134a only.

 

In Canada I believe DIY recharge kits are not allowed to be sold: if you need one there's a leak, and that should be addressed first. Leave it to the pros, who're set up to capture any escaping gas.

 

I agree. There is more to recharging an A/C than a can of R134a. You need to know how much freon the system holds and how much is remains in it. You also need to know what kind and how much oil the system needs, if any. A good A/C tech can get by with a set of manifold/charging gages and observe how the system is performing by looking at the suction and discharge pressure/vacuum, etc.. Then charge the system to bring everything back to spec. He will also know how to avoid Liquid flooding the suction side of the system and causing a locked/damaged compressor.
Often times, if the suction valve has been opened while the compressor is running and hose not connected, air will be drawn in and the system has to be evacuated with a vacuum pump. Plus a new Drier elliment installed.

I 'm not and AC tech myself but have had a crew of them working for me in the navy and civilian industry and this is the kinda stuff they tell me they must do. Many times because someone tired to DIY and screwed it up.

My opinion FWIW.

Steve