hardsand

Hello, I've been reading the forums for several years but this is my first post regarding my 2002 GS300 with about 96,000 miles.

Hot air is all I get from the AC. The lights on the switches seem to operate normally, and I can see the compressor clutch spinning. Hooked up a new set of gauges for a dynamic check and obtained readings of 31 psi low side/95 psi high side (ambient 88 deg F, 40% rh)

The chart I was referencing shows low side should be 45-55 psi and high side 225-250 (at 85 deg) or 250-270 (at 90 deg).

Even though the pressure is low, I thought there would be at least slight bit of cooling. Looking in the sight glass, I could see nothing moving.

Not sure what trouble-shooting avenue would most likely find problem. Any ideas?

sbagdon

You might be cooling, yet just not to what you would expect.

For one... get the pressures correct.

TrueGS300

You just need a recharge. That is way low pressure. Don't just add a can from Autozone. Properly have the system recovered, vacuumed, and recharged to exact spec.

This isn't to you OP. But as a note for consideration for everyone reading because as it heats up approaching summer we are getting a lot of A/C concerns. I have a feeling a lot of people with A/C concerns on forums (not just this one, I am on several) say their pressures are fine because they added a can off the shelf and still don't have A/C. Then lead everyone trying to help on a wild goose chase because they tried to be cheap a$$es. Those cans don't work. They are a major scam and no person without a 609 cert is even supposed to be able to handle refrigerant by law. Someone paid off the right politician to put these into production. If you are charging into a system full of air, over or undercharging, or charging into a leaking system. You won't get A/C. I get customers in for A/C diags daily now that it's getting hot. Many try the can crap. Just gives the shop free refrigerant when all the system needed was a proper evac, vac, and charge.

The 1% of people who buy these cans and have a gauge set, vacuum pump, and all the correct adapters, plus a waste receptacle (if you care to do it right and not vent to atmosphere) and actually know what they are doing are lucky to be able to buy these cans. But the other 90%. You are just wasting your time and money. That is my little rant on A/C recharge cans. I hope this saves at least someone from going out to buy one this summer.

XYZLexus1

Don't ever turn refrigerant can upside down, you are putting liquid in your compressor!!!!. Its a compressor not a pump. Boil some water, when charging DIP not submerge Freon can, Freon will easily enter system.

sbagdon

Guess this is the only 1% I'll ever belong to... then again, I collect SSTs from eBay, so guess that says something. It stunk selling off the R-12 stuff, when the end was near, then having to buy all new stuff for R-134...

Yet yes, agree with your general thought.

Well, at least not on the low pressure side... : )

Angryspice

Um the compressor IS a pump and you do know that Freon turns from a liquid to a gas and back to a liquid as it goes to and from the evaporator to the condensor right?

sbagdon

Just a reminder...

Freon is a registered trademark of The Chemours Company, and is a brand-name for (at least) R-12, R-13B1, R-22, R-410A, R-502, and R-503, with R12 usually having been sold under the branded bottle "Freon-12".

Believe the refrigerant R-134a (1,1,1,2-tetrafluoroethane) is what is used in the 2nd-gen GS, the older Toyota/Lexus models used R-12 (Dichlorodifluoromethane).

The compressor draws from the low-side, compresses the cold gas in to a hot-liquid (that darned compression thing...) to the high-side, passes through the condenser to remove heat and make a cooler-liquid, the expansion valve uses vaporization to spray across the evaporator, then back to the compressor.

I've heard of people slowly pouring liquid in to the high side, as that will go upstream to the condenser and expansion valve, then balance out on the high side... a quick way to get the first 12-16oz in to a freshly vacuum'ed system.

I'm sure TrueGS300 will chip in, if I verbalized any of that incorrectly!

TrueGS300

There is never liquid into or out of the compressor.. it enters the compressor as a low pressure gas, leaves as a high pressure gas and is then sent through the condenser where it turns into liquid. It becomes a gas again through the evaporator and is sent back to the compressor. Always as a gas in and out of the compressor.

sbagdon

I knew you'd chip in.