A/c condenser upgrade

Hey,
I have a 1993 idi n/a in my f super duty roll back. Have recently replace the entire cooling sys radiator, water pump, motor raft thermostat, and fan clutch. Now working on a/c sys. Replaced entire a/c sys except evap. And running 134a. New compressor, condenser, lines and dryer. Ac blows about 55 degrees while moving but gets 65 to 70 degrees at idle on a hot Georgia summer day. I’m thinking I need to upgrade the condenser. My question is I’ve been seeing posts about parallel flow condensers. Can someone point me in the right direction for a direct replacement condenser that is for 134a that will bolt right in my truck or am I gonna have to have some new lines built. Any help would be appreciated!

If it were me, I would add a electric pusher fan in front of the condenser.

Sent from my SM-N960U using Tapatalk

The Parallel flow condenser is the one used in all the F-series trucks from the switch to R134 (~1994) until the '99 superduty was introduced. Problems you may run into but may not with a 1993. If you have a serpentine belt system, I believe you have common hose assembly that runs from the filter/dryer to the compressor and then from the compressor to the condenser. You may find different fittings on the multi-path condenser than on the older style. If you have separate hoses on the back of the compressor I'm almost sure you will have different connection at the condenser on each side. If you have a different connection you can get the newer common hose assembly that has the correct fittings or if you have the separate hose system, you can have custom hoses made with the correct fitting assemblies on each end at napa for a pretty reasonable price. The newer multi-path core is taller than the old design so Ford redesigned the hood latch support to accommodate this change, it has a different offset bent in it to clear everything. You can pull one from a newer truck, cut yours or gently bend your new condenser down near the bottom to clear the old support if necessary.

However, don't neglect your evaporator. After this many years, the lower 1/3 at least will be covered with wet dust, dirt, leaves, ect. and that is ruining your heat transfer ability for your cab air. At a bare minimum you should pull it and clean it, but the evaps are not easy to clean without an ultra sonic bath and the price of a replacement is likely less than your hr/rate x the amt of time to clean it. Up to you but for me it was worth the time to just get a new one.

The newer multi-path condenser is larger than the older one making it more efficient and when you pair it with a variable orifice tube and either adjusting the low pressure switch or getting the newer one for 134, my experience says it works well in the south Texas heat and humidity. That and a switch to make the high idle solenoid kick on when you're on Max a/c makes all the difference in the world.

Ford actually had a number of upgrade kit part numbers that included all the necessary parts to do this but they only occasionally pop up on E-bay. There's a TSB about it and someone on one of these forums has documented what came in the kit and how much better it worked afterward. I've attached a copy of that information that I copied years ago. I haven't checked them in detail for accuracy but it may have some helpful info for you.

When I did my trucks, my AC guy said all the replacement condensers are upgraded to work with 134. Your problem is your fan is not pulling air across the condenser at idle. Both of my trucks do the exact same thing. If I put a lock plate across the fan bolts to the pulley bolts it cools great.

Good info really appreciate it!

Keep in mind that your truck was designed for R12, which is inherently cooler than 134A. I was at Ford electronic and air conditioning back in 1994 when they converted the Mustangs from R12 to R134A at the factory and I was told the number one customer complaint was the air conditioning wasn't very cold. 134A works well as a refrigerant, but an OBS truck a/c was originally designed/sized for R12, so even if it's perfect, do not expect it to cool as well as R12.

I do agree with the above posts that your evaporator and condenser need to be clean, and air flow is super important, as can be seen with your moving down the road versus slow traffic reported temps.

Good luck: cold a/c is very important in the southern states.

try the evaporator off a '89 if it will fit. My truck will blow 40* air on a 100* day. I think this is due to the fan clutch not unlocking and pulling cool air ...I converted mine from R-12 to R134a and Im happy with it. I have the option of going south of the border and purchasing R-12 , where its available, but R-134a is cheaper. Good luck

The electric “assist” fan is a good recommendation. On newer vehicles, that were designed for r134 have a couple of fan setups.

One setup is the radiator cooling fan is electric. So all cooling stack fan forced cooling is done by an electric fan. In vehicles that I have owned, my P71 Crown Vics and both F-150’s in my signature, my Dad’s previous 5.0 Coyote F-150 and current EB F-150 have a large electric fan that cools the stack, it is also used when the A/C is on. The computer turns the fan on at a low speed when the A/C is selected to run. When I get out of the SuperCrew I set the ac to “morgue” (Max A/C, Fan on High). It has remote start, so I hit the buttton and 5 or so minutes later the truck is fairly cool when you get in it. When you walk up, you can hear the fan running.

The other setup, the radiator cooling fan is “mechanical”. All the cooling stack fan forces cooling is done by an engine driven fan, with either a viscous clutch fan, or an electronic actuated clutch. Some application like this, there is just the engine driven fan. My. Excursion is this way. Other applications like this, there is a small electric pusher fan, mounted on the “outside” (grille side) of the radiator, normally down low on the radiator/A/C Condenser so as to not block the main fan airflow. When the A/C is on this fan is on to help the A/C stay cold. I had a Durango, and Infiniti QX56 and have seen a Chevy Tracker (Suzuki Grand Vitata) set up this way.

I'm with the others in that I'd install an electric pusher fan in front of the condenser. Have it powered by a relay that is controlled by the ac switch in the cab.

If your cooling still isn't sufficient, I'd then search for a parallel flow condenser to swap. Yes parallel flow condensers are an improvement over the old tube and fin types, but I think that is only about 20%. So I'd try the electric fan first.

Another item that really helps the a/c system in the converted trucks is a heater core isolation valve that blocks coolant flow to the heater core when you don't want it there. You can built one yourself with some fittings and ball valves or get the ford one that is vacuum controlled. Being vacuum controlled and plastic means it isn't as efficient as a one built with ball valves but it is automatically switched on and off by teeing into the vacuum control line that runs the recirculate door that is right next to the heater hoses as they go into the firewall. Anytime you switch the system to Max A/C this line has vacuum to engage recirculation and will isolate the heater core, in all other positions it allows fresh air to come into the cab and will allow coolant to flow to the heater core. It was commonly found in ranger and aerostars and windstars of the era. Look up Motorcraft YG350.

The OE sized blue orifice tube does not play well with R134a. The parts stores do not understand that you need a smaller orifice with R134a.I have been using the range tube and getting much cooler AC out here in the desert.

I had a ‘93 that I converted to 134 and it was like you say, cool not cold driving and warms up when not moving. I played and played with the charge, I always vacuumed and weighed the freon. I even used a digital thermometer to check the inlet and outlet of evaporator as I added 1/10 of an ounce of freon at a time. I finally put in a variable orifice tube and it was a different system. It was around 40 stopped and cold and cycling driving.
I had thought about the orange tube but never tried it.