Alfa Romeo Forums banner

1 - 4 of 4 Posts

·
Premium Member
Joined
·
26,820 Posts
Discussion Starter #1 (Edited)
When converting Alfa 164 12v 91-93 R12 A/C system to R134a

Use NAPA 409903 FOR LOW PRESSURE side at PDI/POA valve
Use NAPA 409902 FOR HIGH PRESSURE side at receiver dryer

Remove old R12 valve cores and install these fittings with their new vqlve cores onto R12 fittings.

Use LP blue capped fitting on POA valve and HP Red capped fitting on line behind receiver dryer behind fals firewall.
 

·
Premium Member
Joined
·
26,820 Posts
Discussion Starter #2
Time to bump this up and put it in my sticky, too
 

·
Registered
Joined
·
447 Posts
Correct me if I'm wrong but on the old R12 system, the fitting on the high side is the same as the low side. The new replacement dryer still has the old type R12 Shrader valve.

If that is the case, you have to use two NAPA 409903 and get the appropriate hose adapter to make the high side work on the gauge manifold.......

Or not bother and just have an R12 hose attached to the high side.
 

·
Premium Member
Joined
·
26,820 Posts
Discussion Starter #4 (Edited)
Correct me if I'm wrong but on the old R12 system, the fitting on the high side is the same as the low side. The new replacement dryer still has the old type R12 Shrader valve.

If that is the case, you have to use two NAPA 409903 and get the appropriate hose adapter to make the high side work on the gauge manifold.......

Or not bother and just have an R12 hose attached to the high side.
Your wrong.
Use NAPA 409903 FOR LOW PRESSURE side at PDI/POA valve
Use NAPA 409902 FOR HIGH PRESSURE side [near] receiver dryer.

Yes both R12 fittings were same size on POA valve and hose/tubing near dryer but correct adapters are needed to use R134a gauge hoses.

The R12 fitting on the dryer is where the trinary switch attaches and some dryers do not come with R12 fitting for trinary switch. There is a R12 adapter fitting available for those dryers.
 
1 - 4 of 4 Posts
Top