AC Evaporator? What's the difference between pre-94 & 94-up?

[itsacrazyasian]

Ford does not sell that retrofit condesner anymore. Visteon still has a part number, but what they did instead was make the old style standard thread condenser a more modern crossflow style condenser which improves cooling with R134A. So usually when you look up a condenser in a pre 94, they make two different designations, one being a tube and fin (R134A) or serpentine (R12)

 

[junk]

Goo info guys. Ill probably stick with 134 since its easy to get. Ive had really good luck the conversions ive done before. Also ill have to eyeball the evaporator. Before i order. The links i posted have the same core so it looks like theyre both setup for r134 already.

 

[itsacrazyasian]

Ford never changed the evap core size between the R12 and R134a evaporators. If they did, its so subtle that the R12 evap fit in my R134a case. The actual difference is in the drier and the threads for everything. I found that out when i swapped my gas 351 in my 94 to the 6.9 idi. The threads are the only difference. The drier is a little different too.

 

[DaytonaBill]

Ford never changed the evap core size between the R12 and R134a evaporators. If they did, its so subtle that the R12 evap fit in my R134a case. The actual difference is in the drier and the threads for everything. I found that out when i swapped my gas 351 in my 94 to the 6.9 idi. The threads are the only difference. The drier is a little different too.

Which orifice color or size are you using on your CC?

I've been using a VOV, can you explain why you would rather not use one?

Thanks...

BTW, the state of Arizona has been retrofitting their vehicles to propane and every day more and more shops are expanding to propane with no complaints... That information is almost two years old...

 

[itsacrazyasian]

Which orifice color or size are you using on your CC?

I've been using a VOV, can you explain why you would rather not use one?

Thanks...

BTW, the state of Arizona has been retrofitting their vehicles to propane and every day more and more shops are expanding to propane with no complaints... That information is almost two years old...

First off. Propane used as a refrigerant is not allowed by the EPA. R290 (which is highly refined hydrocarbon refrigerant with the same composition as propane) is banned for mobile use. Many blends are legal though.

2nd, i dont use VOV's with hydrocarbon refrigerants. To save a bunch of typing on my lunch break. Basically it boils down to how a VOV reacts vs a FOT (fixed orfice tube) to the alternative refrigerant because the VOV was designed for traditional refrigerants. A VOV varies based on head pressure and vapor quantity. industrial 12A or R290 operates at much lower head pressures. If you want me to write a long paragraph about how subcooling affects a VOV with R290 i'd be happy to.

A VOV is not to be mixed up with a TXV.

 

[riotwarrior]

Wow...good read..beyond me for most part...gotta recharge /fix up the cooler in the Bronco, may wait may not...my diesel truck outside has AC so I'll be pinching most parts from it when I convert to diesel....should make this thread a sticky...

 

[DaytonaBill]

I was under the impression that Industrial ES-12 was a blend, for two reasons...

1. To carry the oil through the system
2. to be eligible for DOT approved ground shipping when packaged in the cans...

Also, last I checked, the State of Arizona was using propane blends (it has to be a blend, otherwise you would burn up compressors). The EPA hasn't restricted the State of Arizona, so either Arizona could give a rat's **** for the EPA, or there is a misunderstanding on the "propane blends" that are offered for public consumption. If it really was banned, then why hasn't the .gov cracked down on this activity? We all know that the EPA would swoop down on that stuff so fast that your head would spin, as evidenced by their past examples...

No, I don't need a treatise on the VOV, I merely just wanted to know, as per my first question, which orifice tube you used in your CC, that's all... I could care less about the one I'm using... I'd rip that sucker right out if I thought that it might not operate properly with the

"propane blend"... ​

 

[DaytonaBill]

Which orifice color or size are you using on your CC?

Never mind...

It's the...

Motorcraft YG-345 A/C Orifice Tube!!!

Hey crazy! Thanks for all of your help!!!

 

[itsacrazyasian]

the blends are perfectly legal. R290 will carry oil. No issues with that and mineral oil at all. Your previous post did not mention blend. Just had to clarify that. The EPA is a PITA.

edit: This is a disclamer, don't put BBQ propane that you purchase to cook with in your car... An individual may get a small fine from the EPA. Someone like me with an EPA cert will lose that certification hence why i'm clarifiying.

Basically put for those that want to know. A TXV or thermal expansion valve behaves differently than a Variable Orifice Valve because the VOV reacts only to head pressure and vapor. A TXV has a capillary tube (as small as it may be, it still does) and will react based on temperature to help maintain proper evaporator flow. With the VOV, you'll either flood the evaporator or it'll flash to gas that you lose much of the cooling capacity of the refrigerant.

My tube is red if you really wanted to know.... And iits not from that stripper either.

 

[typ4]

ICK.

 

[DaytonaBill]

My tube is red if you really wanted to know.... And iits not from that stripper either.

Ah-ha!

So your tube is smaller?

Just so that you know, yesterday my pop valve went off and just before that happened, my A/C started cooling better at low rpms and speeds than at highway speeds. Methinks that my VOV is malfunctioning so I guess I'll have to postpone my move to Houston till later... I was going to move tomorrow... Oh well...

I'm going to yank that VOV out and check for debris. I used a Autozone compressor, so that might have something to do with the VOV, but on the other hand, if the compressor can produce high enough pressures, I don't think the 'pressor is bad. Just the same, I'm going to be looking for debris and flush everything. I will take the condenser out and lay it down when I flush... I just might use that DEC 46 PAG oil.

Oh well, I'll start on it tomorrow...

Oh yeah, since the red orifice tube (.062") is smaller than the original blue orifice tube (.067") and the blue orifice tube is same size as the VOV (when fully open) that is rated for use in less than +105 degree temps, would I be correct to say that R-290 requires a slightly smaller opening?

I wish I could use an adjustable expansion valve, but it's way too much work to convert our systems to TXV...

 

[itsacrazyasian]

Ah-ha!

So your tube is smaller?

Just so that you know, yesterday my pop valve went off and just before that happened, my A/C started cooling better at low rpms and speeds than at highway speeds. Methinks that my VOV is malfunctioning so I guess I'll have to postpone my move to Houston till later... I was going to move tomorrow... Oh well...

I'm going to yank that VOV out and check for debris. I used a Autozone compressor, so that might have something to do with the VOV, but on the other hand, if the compressor can produce high enough pressures, I don't think the 'pressor is bad. Just the same, I'm going to be looking for debris and flush everything. I will take the condenser out and lay it down when I flush... I just might use that DEC 46 PAG oil.

Oh well, I'll start on it tomorrow...

Oh yeah, since the red orifice tube (.062") is smaller than the original blue orifice tube (.067") and the blue orifice tube is same size as the VOV (when fully open) that is rated for use in less than +105 degree temps, would I be correct to say that R-290 requires a slightly smaller opening?

I wish I could use an adjustable expansion valve, but it's way too much work to convert our systems to TXV...

Supercool sells a inline filter that will snap into the quick connect of the inlet to the evaporator to keep the orfice clean. In addition, that filter is cleanable.

Converting our vehicles to TXV is pointless. They CAN cool plenty when set up correctly. But the newer fords that went to expansion valve... they're just nuts to how cold they get.

As for your VOV, it sure sounds like it got hung up, especially with the better cooling at low speeds. R290 needs a smaller opening.

 

[junk]

If running R134 would you run a VOV? Or just a regular Orifice tube?

 

[DaytonaBill]

Supercool sells a inline filter that will snap into the quick connect of the inlet to the evaporator to keep the orfice clean. In addition, that filter is cleanable.

This one?

Universal High Side In-Line Filter

You must be registered for see images attach

 

[itsacrazyasian]

That one is serviceable too, but its one you need to cut a section of aluminum to use that (its compression fit) which increases a chance for a leak. I'll find the part number for the other one. Still at school, been a crazy day with seeing a girl get tazed and the campus cops running around.