View Full Version : Charging R404A in FGAS practical

21-02-2013, 08:49 PM
When you are charging a system with R404A in the FGAS practical, what order should you open each valve. This includes valves on the gauge line as well?

I was asked this question but was un sure on the correct order!

21-02-2013, 08:57 PM
I assume that the unit have been evacuated and that your manifold set is still connected.

Close all valves on the manifold set, disconnect the vacuum pump, yellow hose? Connect yellow hose to gas bottle.

Crack open the gas bottle valve, bleed a small amount of gas from the yellow hose connector at the manifold set. This clears air out of the yellow hose. Close bottle valve.

If liquid charging then then open bottle liquid valve or invert bottle if it doesn't have a dip tube (this refers to any gas not just 404). Now open the high pressure valve of the manifold set to let the refrigerant into the system. Start slowly until the system pressure is above zero.