A.C. Question?? Who Knows there A.C. Systems!!

[Jim Adams]

I have a question about the liquid return line on the Fords A.C. system,,Do all of the liquid lines have to be slightly restricted to get the vapor to turn to liquid or is that Just fords way of putting an orifice in line,,,Could you use a larger diameter liqiud line and just put your orifice strainer in line say at the evaporator? The liquid line that goes from the condensor to the evaporator has a biult in restrictor/orificeand only has like a 1/8th inch passage threw it ,,is this for a reason or just the way fords do things?

[Jim Adams]

heres what I did,,on the Ford having the orifice in the middle or closer to the condensor is isnt very efficient ,,so I cut the liquid line took the orifice out ,,welded the line back together and then put a what they call a variable orifice valve in at the evaporator connection,,see the hose almost freezes over half way down the liquid line,,this is a waist,,you want it to vaporize in the evaporator giving you a more efficient and colder evaporator core,and using the Variable Orifice Valve lets the flow of refrigerant change as it is needed,,ever notice that when going down the road your vehicle is colder than when sitting idleing? well thats because there is about 7lbs a minute going threw the orifice and then at an idle there is about 5 lbs a minute thats why its colder going down the road ,,with the variable orifice valve and the orifice being at the evaporator instead of mid-line on the ford Tbirds it will give it 7 lbs at an idle as well as 7 lbs cruising ,,it has a metering rod and springs that adjust it depending on the high side pressure!! COOL fix for you Ford Tbird guys !!

[CDJr]

Congratulations, Jim, youve just re-invented the thermostatic expansion valve.