Topping off A/C Refrigerant

I top off 04 09 quite regularly usi g reg 134 oil and refrig. My personal car runs HC 12A but they no like that here. Like colder than R12 here . Nothing failed because of oil or refrig i use as it's been used by me for over 20 years in hundred vehicles some on road still with Air still working.good luck

 

I top off 04 09 quite regularly usi g reg 134 oil and refrig.

I put a gun to my head and pull the trigger quite regularly. I've been lucky so far since I've always used crappy ammo and they've always been duds.

Now, for real. If you've merely had a very slow degradation of performance over many years, it's unlikely you've had any significant oil loss. I wouldn't worry about adding oil at all. Just use the procedure from the repair manual. It's not the 'most perfect' way to maintain the system, but it works well if done carefully.

 

What's the sight glass do ? That's wer ya start . If you want to just do something to be doing it take some synthetic air conditioning fixing stuff whatever that crap is called i got three or four cans around here hook it up give it a shot or two while the car is running while looking at the sight glass you want to see bubbles every few seconds in the sight glass you don't want it to be solid clear you don't want tons of bubbles you want to see a little bit about very little and then measure your temperature coming out of your vents i bet they'll be very cold now i'll go play with my gun which i don't actually own to be honest about it never have maybe i'll just go fly the warrior instead

 

@lech auto air conditionin has posted often on the topic of topping up.

 

If needed because of a leak, the recommended recharge method is to remove the refrigerant, weigh it to determine if there is loss, ideally find and fix the leak, vacuum test and recharge by weighing it in. Even with a sight glass this system is different as it is a variable capacity (speed) system.

 

We have a wiki page giving the various ways to access it.

 

Look at this post I threw up a while back. May want to read the whole thread also. It includes the repair manual chapter.

A/C works but no cold air. | PriusChat

 

You have a leak in the system. You can keep messing around or maybe over charge it and damage the compressor. You can easily damage the compressor compressor running it on low or not charging it properly with a can from an auto parts store.

Take it to a local ac shop there all very familiar with a Prius. They'll put die in it and find the leak. Hopefully its a loose coupling.

Its a 17 year old car so Don't be surprised if its the evap coil under the dash. Pretty common. Pretty expensive. The real $$ bingo though is if the compressor fails. That's really expensive. So...tik tok.

Mine failed at the evap coil owner says they see it alot in a Prius. They knew what they are doing cause the ac was uncomfortably cold when they finished. Ran great. The ac system in a G2 is excellent if running properly.

New evap $1100.

 

For the whole job, right? List price on the evaporator itself looks like about $400 at the dealer.

 

Holy moley....not every AC system that is weak has a catastrophic failure/leak that needs immediate component replacement or thousands of dollars of repair. .it's a 2005, jc. 17 years of usage. A typical brand new car off a dealer lot has an AC leak. EVERY automotive AC system has some amount of leakage. They are not 100% perfectly sealed systems!! A minor top off and most are ready to go for years again.

Just like the people that keep claiming "'my car engine burns zero oil" and your car burnsa quart of oil every 5000 miles, so you need a new engine installed. Knuckleheads, every one of them.. Every car ever made with an internal combustion engine burns oil from the second the engine is started. Those who say they don't do not understand how an engine works.

 

Leave A/C jobs to A/C shops. Not even regular shops are qualified to do them, let alone the owner.

If there is a leak, it needs to be found, fixed, and the system evacuated before it is refilled. You will have to replace your A/C dryer as well.

 

That's just hard to do right, is all. The subcooling design of the system makes it hard to tell when the right charge is in it, other than by taking it all out and putting a known amount back in. (Extra credit for weighing the amount taken out to know how low it was.)

For a shop that already has the equipment needed, that's an easy job.

 

Most of your assumptions on typical residential units are correct as are methods to top off the majority of residential and mechanically driven car compressors.

Gen2 Prii, properly charged and free of non-condensables have cold AC that can easily handle our blazing Texas summers much less milder northern temps.

However there are huge differences in Prius ac compressors versus typical home or auto ac. It is variable speed, variable capacity. Driven by an integrated three phase electric motor. Designed to allow cooling without the engine running. Expensive to replace and more complicated to charge.

"Normal" home and auto ac compressors are single stage compressors. This makes standard systems easy to charge by a sight glass or by superheat or subcooling. They still need a clean system best achieved by pulling a vacuum and fixing leaks. Leaks are not a given when you have a hermetically sealed compressor on a residential system although flexible piping and coils on vehicles are likely leak locations. On a home system leak locations are usually the inside evaporator; a vehicle with flexible hoses and an exposed condenser have more leak locations.

An electric variable speed compressor is different. Instead of running 100% all the time, it could be anywhere from 25% to 100% making it easy to overcharge. Sometimes people excessively overcharge these systems by 200-300%. Excessive charge can blow seals and ruin a very expensive Prius ac system. Which usually requires replacement of the condenser, the txv metering device and the compressor. In addition, the wrong refrigerant oil can short out the compressor windings. Bubbles in the sight glass is not definitive. Spending a couple of hundred is well worth the expense.