a while back i was changing the heater core and was wiggling the HVAC unit behind the dash to get to the core. in doing so, a clip that holds the A/C line together where it goes through the firewall popped off and the system blew out. I know the basics of how the system works, but not sure about when things like this happen as far as being able to refill it with just using cans of Freon from the parts store, or if i need someone with proper gauges to recharge it. I hear about the whole high side, low side thing but unclear how that works. Would the whole system have empted or just part of it? if i can do it on my own, is there also something i need to do about checking/adding oil to the system? also clueless on doing that.

 

if the joint retainer clip popped off, then you should put new o-rings on the joint and put a new retainer clip (that's if the old one is lost or broken) Be very careful pulling the connectors from the evap coil to the accumulator/engine compartment apart to replace the o-rings because the lines are fragile. Then evacuate...side note, you might wanna consider replacing the accumulator and orifice tube at the condenser if you're feeling bold n have the extra time n money to burn AND if your gonna separate the joints anyhow. As far as compressor oil...if the compressor is still good and nothing blew there, then don't worry about the oil. The system uses a predetermined amount/weight of R134, but you still want gauges so you don't over or under fill the system. Now if you have an accurate small measurement scale...nah, even then, gauges are still very important. They'll tell you the health of your system. You can get a cheap set on amazon for around $25. The high side in particular tells you if your compressor is any good anymore. The hotter the wx...the higher the hi head pressure should be.. Low pressure does more to tell you the condition of the rest of your system AND as a bonus it can prove whether or not you got enough or too much freon.

 

thanks for the reply. As far as the condition of the system, it was working great until this happened. Guys at the part store seem to think I can get it pretty close using the recharge cans with the gauges on them. I don't know if "pretty close" is good enough or a bad idea. Anyone have opinions on the gauged cans? I'm thinking i'll give it a shot and see what happens.

 

There should be a tag under the hood that will tell you exactly how much R134a needs to go into a completely empty system.
Seeing as how the system was open to the atmosphere the receiver dryer needs to be replaced then you need to pull a vacuum on the system
for not less than 30 min ( I recommend an hour ). Unless you live in a vacuum, I will guarantee you that moisture got in the system,
R134a loves moisture and moisture in an AC system is a bad thing.
Then let it set on the vacuum for another 30 min to determine if there are any leaks, if no leaks then put in the amount that is on the tag under the hood.
As for the oil you should be OK but the oil gets dispersed throughout the system mixed with the freon, it doesn't just stay in the compressor

So yes you do need a set of gauges, a vacuum pump, and some working knowledge of how an AC system works.
As for the guys at the parts store, I would take what they say with a grain of salt.

I attached a basic charging chart, download it and teach yourself how to use it.
Also never try to charge a system on the High Side

 

The system being exposed to moisture (since I don't even know if it got put back together right...snapped it back together without looking if o-ring was good or even there) and needing a vacuum applied is good to know. I searched around for info about recharging the system, but not really finding anything clear about a ststem that came apart. I had a feeling there might be more to it. I think i'll just take it on into the shop. don't really feel like messing with it at this point (too much other stuff going on)

Thanks for the helpful info

 

Paying someone else to deal with it should ensure that it is done properly. I suspect that when the refrigerant exited the system, it likely took a fair bit of the oil with it......

 

also had a bad feeing about that. I don't really know how that oil works or moves through the system, but as hard as it blew out, I was wondering if it moved oil with it. as much as I don't like taking it to a shop, I think some things are worth the extra dollars Thanks

 

I do that every time I go there

 

It used to be that the guys at the parts stores actually knew what the parts were all about, and could offer good advice. These days, with the big chain auto parts stores, that simply isn't the case. Most of them hire young kids right out of school, that don't even know what a ratchet is......

 

this is true. going to the big box hardware stores is kinda the same deal too....trying to describe something you're looking for to someone is sometimes fun. I've had younger people pull out their phones out and google search to see if they even sell the part at the store.