I recently had my a/c serviced, refilled with freon and oil, and checked for leaks...I also had them change out the condenser. I don't think my a/c is blowing as cold as it should. It diffenately doesn't feel close to how a new car's a/c feels... was wonder if anyone knows how I can get it colder?

 

A lot times they don't get the correct charge on the system. Do you know if they also replaced the orifice tube? It's a easy fix, but one that most money making shops forget to do. (sometimes on purpose)

It's showing that your car should have a charge of 33.44oz. Take back to the shop, and make sure that they check the charge on the system.

 

also remember that your car has been retrofitted to 134a and most times they intentionally undercharge the system to cover their butts from being sued if the pressure gets to high

 

not sure...where is it located and what does it do?

 

they supposively refilled it with R12......

 

The orifice tube is located in the line. Before the evaporator. The system has to be recovered before it can be replaced. Check and see if they listed it. If not, you might have to go to the shop and check and see. It's usually a good idea to have it replaced anytime the system is worked on. If not replaced, atleast inspected.

edit the orifice tube is the changing point of pressures in the system. It restricts the refrigerant coming through, causing a high pressure to build up in the condenser side, and a low pressure in the evaporator side.

 

They didn't change it...just refilled system and stuff and put new condenser in... so the orifice tube allows refrigerant through, to cool it off.....and if mine is bad, not as much is getting through? is that how it works....

 

ohh, not good. The orifice tube has a screen, that collects particles and changes the pressure. I could go into exactly how the system works, but that's too much to type. If you want, I can email it, but I don't feel like putting it up on here.

I hate to say it, but you might have to take it back and have that replaced too, also have them check the receiver dryer.

If that doesn't cool things down enough. There might be a problem with the switches, or sensors.

 

Before you do any of that, make sure they charged the system right. If you don't have manifold gauges, go back to the shop and ask them to check the charge because you don't find the system up to par. Then, WATCH as they do it and make note of the hi and lo side pressures. Make note of the ambient temp as well. Post them here and I'll check my FSM to see if they're within spec. If your car is an 89-92 it will be R12 unless it was retrofitted. The R12 system on the Max didn't have an orifice tube, it had what Nissan calls a 'throttle suction valve', which I think is what everyone else calls a TXV valve. Regardless, I think it can still become plugged up. The pressures can also show this - (i.e if the low side is OK, but the high side is too high the TSV could be plugged etc etc)

Also, the shop may have put a cheaper brass and copper condensor on your car which way underperform compared to an aluminum condensor. Your car probably originally came with an aluminum condensor. Just something you might want to check. Definitely, starting with the pressure is the first thing to do.

 

If they didn't retrofit your car to 134a , then you paid out the az$ for the 12.
they also should have replaced the Accumulator/reciever-drier at the same time

 

Ya i need to clear some stuff up...i was smoking something when i posted..
They refilled with R12( yes I paid a **** load compared to R134) and they changed the Reciever Dryer thing....not the condenser(my mistake).....
SO I got new oil, dye, freon, and reciever dryer.....
and my car is a 92....I remember them saying something about the expansion valve( which is the orifice tube i think) to replace to make colder, but they wanted more money so I didn't do it...I thought new freon and a condenser would make it colder...but it looks like Im going to have to wait until next summer and just have them put a new orifice tube in or whatever my car came with...unless this is something maybe I can do on my own.

 

you can't work on an R12 system yourself unless you are MACS certified.
the expansion valve regulates the flow of the freon.

 

Yeah, EPA is starting to crack down on everything in regards to the A/C system. Not to long from now, you won't even be able to buy the R134a cans unless your certified..... Or did they already stop the selling of the cans on shelves. I can't remember for sure right now.

 

drive it on the highway. In the city my AC is so-so but on the highway it will freeze my fingers off... on #2, #4 just freezes them off faster.

 

you should've got duracool. it's a fairly new refrigerant that some cars are getting their systems recharged with. apparently it's as cold as r12 but environmentally safer like r134a. i heard that duracool will soon replace r134a on 2006 production cars. but that's still under speculation.
it's very cheap to purchase the amount you need for your system too.
apparently it works with r12 or r134a fitment systems so no hardware would need to be changed.
it also works as a sealant if you have any leaks throughout your a/c system.

so if you end up getting the a/c refilled again look for duracool.

 

I read the Duracool post above and did oodles of research I won't bother reproducing in full here.

In a nutshell:

There are only about three coolant ingredients approved by the EPA for car A/C systems: R22, R134, and another R whose number I forget. Of these, R134 is the least inconvenient.

Why is the EPA so restrictive? One reason is safety. Not just the world's (although that counts too), but YOURS. Duracool, and one of its competitors, contain hydrocarbons (propane? I can't remember which) that can... uh... er... set your car on fire and burn it to cinders. Like that.

I wish devoutly there were an infallible shortcut to changing over your hardware for an A/C recharge. Alas, there is none. There are brands of R134 that have eentsy amounts of additive in them so that you don't have the added inconvenience of adding oil as part of the coolant change. But a proper changeover with these, unless you can still find R12 somewhere, is your best real option.

 

check your dryer. I think there is a little spy glass that will let you see the color of the freon. it should be a homegenous milky white.

I am not sure if maximas came stock like this though. When i change my dryer it had a spy glass, cant remember if it came like that on the orig.

 

R22 is home use not mobile, I know you meant R12 though

 

Personally I think the danger of hydrocarbon based refrigerants are a bit overstated... there isn't that much of it in there, and I think the circumstances where it would ignite into a fireball would be no more likely than that happening with gasoline. Yes, it is propane by the way, and so are most of the similar products to it.

An air conditioning guy I know suggested the possible use of MP39 in an R12 system, but I didn't ask for any details... and I'm willing to bet that you're not supposed to use it either.

 

There's also a giant container of explosive liquid/vapour in your car that can...uh...er...set your car on fire and burn it to cinders. The EPA doesn't give a rat's *** about it. It's called gas. Believe me, I'ved used Duracool, and it's a viable, cheaper alternative than retrofitting to R134. I didn't blow up and it cooled as well as the R12 I used to have in my old '88 Max.