I got my Sanden A/C conversion hooked up and charged yesterday. I'm highly disappointed in the fact this thing doesn't blow very cold. I'm probably going to go back to R12 freon, hoping that will help cool better.

More importantly: When the compressor is engaged, the temp gets up near the edge of the normal range. I was watching the gauge all the way home, worring the car was going to over heat. Finally, I turned off the A/C and rolled down the windows. After the car cooled down, I removed the radiator cap. There was still coolant in the radiator, so my fears of a leak weren't realized.

How much would a 4-row radiator help?

 

your engine temp sounds normal to me make sure you have a overflow.gotta remember you got a cast iron block and heads they hold heat.yes r12 is colder but youll cry when you see the price.you sure they didnt put too much or to little 143a in it also did they change the evaporator and inline filter with the right oil for the system.

 

The compressor is new. The condenser is new. The dryer is new. Two of the three hoses are new. The expansion valve was replaced last October. The only thingsnot neware the evaporator and the small hose (the one with the sight glass in it). I watched as the mechanic built the hoses, added oil to the compressor, checked for (and fixed) leaks, and charged the system. I don't know how much R134 he put in, but he obviously knew what he was doing.

I'll look into an overflow for sure.

 

What are your high and low side pressures on the A/C system? If you do not have a set of R134 pressure gauges, look into get some. They will tell you a lot. I use them pretty regularly to keep all my cars cooling. The high side should be about315-325psi whenair temp is in the upper 90s. The low side should be about 50-55. If the pressures are less than this, it could be low on R134. 25psi on the high side can make a big difference in the cooling ability of the system. Keep in mind that the pressures are depended on the temperature of the air outside. Get a scale to make sure you are in the right range.

 

In addition, ideally, 134a should use a different expansion valve than r12,andas a rule, the better an A/C system is working, the more heat will becarried to the condenser. In other words the better your ac cools the inside of the car, the more heat will be dumped in front of the radiator.

A four row would probably help this situation, but ifI were in your position, I would not worry about it much unless (or until) I started having overheat issues,,, it will be fall soon anyway.

I have converted many r12 systems to 134 without ever changing the expansion valve or orfice, there is a difference in cooling ability but not much.

It is my understanding that the early Mustang stock A/C systems have their limitations..... +anA/C always seems colder when it blows righton your face, those underdash units have a hard time with this.

In my experience, 134a cools almost as cool as r12, but it takes quite a bit longer for it to get as cold as it is going to get.

Just as a side note, one time I had an A/C failure in a truck and ended up going to a shop that repaired comercial refrigeration units on tractor trailers, they repaired and charged my system.

I don't know what kind of refrigerant they put in but wow.A week or so later I was driving nearVan HornTexas in the heat of summer, (100+ degrees) thepassenger vent was pointed toward the doorand the vent window exploded.... bam.... This was an old r12 system converted to 134a, but filled with what must have been "super refrigerant"...

If the defroster vents were on, it would literally put frost on the windows in 75+ degree weather.

For those in Florida, I had this done at a Thermoking shop next to the TA Truckstop in Wildwood Florida.

I forgot to mention that your A/C may work better once the new compressor breaks in a little bit. I have noticed that for one reason or another, that when I install a new compressorthe A/C seems a little warm for a while, my hypothisis is that the new compressor is tight, and therefore putting extra heat into the system via increased friction. If I am right, both of your situations should improve in time.