Note: If you're not comfortable with working around A/C systems, take it to a professional to get it done. Only service your own A/C system if you know what you're doing, or if you're crazy enough to take on the task. You are dealing with refrigerant under high pressure, and if you don't know what you're doing you can injure yourself. If you do a R152a conversion, make it clear that there's R152a in the system.
Getting the tools
In order to do any A/C service on your own, you will need to get the proper tools.
If you have one of these, find your nearest trash can and throw it away. These cheap gauges are as accurate as your daily horoscope, and they only "show" low side pressures.
Then, run to your local auto parts store and pick up one of these. I picked mine up for $50 at the local Harbor Freight.
Manifold Gauges are absolutely critical to any A/C service job. In order to diagnose your A/C system properly, you will need to know the pressures on both the high and low sides.
You will need a vacuum pump. They cost around $150 at Harbor Freight, but you can rent one from an auto parts store.
You will need a side-tap. I had trouble locating one at the local auto parts stores, so I ordered one online.
Charging the system
After overhauling the A/C system, I vacuumed it down and let it sit overnight. The next day, I charged it up with R152a, making sure to purge the hose first. H-Body cars require 2 pounds of R134a, which converts to 1.28 pounds of R152a.
You may be wondering why I didn't go with R134a, and here's why.
- R152a(otherwise known as computer duster) has a better cooling capacity than R134a.
- R152a has a way lower environmental impact than R134a.
- A 3 pack of computer duster costs less than 1 can of R134a.
- It takes less R152a to charge the system.
Now, the A/C in the Bonneville works better than ever, and I saved a lot of money.
