What RPM'S should your car be at when ckecking your a/c with a manifold gauge?


#1

I just bought an a/c manifold gauge set for testing my car’s a/c system. Should you test it with the the car at idle speed or should it be higher?


#2

Working with a vehicle AC system can be very dangerous. From your question I assume you have no experience so I will offer this advice: Buy a repair manual and study it or have an experienced AC mechanic show you the basics. This is an area that you don’t want to tinker with without being safe.


#3

When checking the rate of charge of an AC system, the engine should be idling between 1,800-2,000 RPM’s and a large fan should be pointed at the front of the vehicle. You’re trying to simulate the vehicle is being driven down the road.

Tester


#4

Tester is correct of course and I’ll offer only one piece of advice since you’re new to A/C gauges.

NEVER open the high side valve on the gauge set when a can of refrigerant is tapped and the dispensing valve is open. This can cause a refrigerant can explosion which can cause frostbitten fingers in seconds or permanent blindness instantly if any refrigerant hits your eyes. Buy a pair of safety goggles anyway.