A/C conversion? Charge yourself or take to shop?

Curious what others have done...

Just finished physical install of an Original Air Group underhood kit on my Challenger. Same company and similar underhood components as Classic Auto Air (sanden type compressor), but uses factory parts under the dash.

I'm weighing a couple hundred in tools to check and charge it myself (vacuum pump and gauges) versus a couple hundred to take it to shop to have them leak check it and charge with refrigerant. For my part so far I'm most concerned I may have over or under tightened at O-rings or not crimped the hose connections well enough, as this is my first time dealing with A/C parts.

What have you all done? How hard are these kinds of systems to charge correctly?

Also, I don't much trust the A/C shops in my town so there is that I have to consider.

I bought the gages and pump then did it myself. Always thought it was complicated, not. A lot of diy on internet.

If you already have the tools to do the job, I would do it yourself. The investment in the tools will make things more convenient for you because you can service and check things whenever you need to vs having to take
time out of your day to take your vehicle someplace and hope everything can be done that same day.
A/C maintenance is not difficult at all. I do all my a/c servicing and repairs at my house. Vacuuming the system, charging, etc is very easy to do. Been doing it for years.
If you don't trust the shops do it yourself.

What's an affordable vacuum pump you could use for both home and car?

I always buy the tool and do it myself. Always.

LINKY ONE, Should do both, might want to shop a bit to see if you can find one cheaper yet ?

LINKY 2, Car only
Uses compressed air to pull a vacuum Might work on a house but could take a while depending on the size of the system

If you do it yourself don't forget to add PAG oil.

Check with the supplier of the kit/components as most "KIT" compressors are loaded when shipped

New compressors come charged with all the oil the system will need. Kit instructions usually warn not to add additional oil.

Those cheap amazon pumps work like a champ, on a house system set it up so you can have a box/shop fan on it to keep it cool.

Nobody touches my vehicle but ME. Except for something line a wheel alignment for which I am "right there" while it is being done.

I used one of the cheap HF vacuum pumps. Uses compressed air to pull vacuum.

I think it was about $15

after studying AC systems for years, before it became a mandatory working item for my wife and i, it finally became clear to me how it worked, and it wasn't as complicated as i thought it would be.
this was in the few years after the OEM's converted everything to R134.
so for a few bucks invested in gauges, and fixing a vacuum pump that was tossed in the scrap barrel at work, i had all the items necessary to do repairs.
first order of business was an auction minivan with a cycling clutch, but warm air.
going through that, it was discovered a line had a slight groove wore in it, so new line[s] o-rings and a drier later, it blew 40 degree air !
nothing like success to urge a guy on !

since then, i have graduated to detecting leaks with the ultra-violet light and system dye stuff to removing and replacing complete dash assemblies for evaporator replacements. [not fun, and ALWAYS replace the heater core while you are in there with a QUALITY replacement.]
as i found out [or learned], it's not as hard as it appears if you research what it takes to do the job first, then take your time doing the actual repair with copious notes, diagrams [if necessary], and pictures if you need them. a FSM is helpful as well.
if i can do this successfully, you can too !

anyone have a gauge set recommendation?
cheap ones seem to be all over the place.

I'll get flack for this but, if you charge a new system by the weight recommended, there's no need for a gauge set.

A little tougher when doing a conversion since R12 and R134 require different weights in the same system. Some new systems are engineered to the point they all take the same (I think classic auto air is 24oz R134A). Updating some to new and reusing some old parts gets even trickier. At least as I have found out so far since I made this thread.

So I guess I did okay. Held vacuum fine. Still gonna be paranoid for months about not perfectly tightening O-ring fittings and slowly leaking away $60 bucks of refrigerant.

Used the smaller electric vacuum pump from HF and the gauges set from also from HF. A few small doo-dads from Auto Zone like a can valve, thermometer, etc. And I am in for about 200 in tools alone, but now I can figure out why my other car isn't blowing as cold as it should. Thanks all, A/C is just one of those few things I have neve messed with, always scary the first time learning and worrying about mistakes.

First time ever feeling cold air from these vents in the 30 years I've owned it. In Georgia, the car has basically been un-drivable in the summer months due to miserable heat and humidity. Evaporator drain creates a solid stream, not a drip, after just driving around the block.

On the other car not cooling well it could be alot of different things. But one few know is if it's 134 an it's overcharged it won't cool right. Pressure needs to be set according to the temperature.

I've been in the refrigeration trade for 30 years, I treat the weights on equipment tags as the starting point not the optimum point.