Vintage AC - what are your numbers?

[Rian_Colorado]

Hey all -

I (like many of you) have the Vintage air setup from FFR. One of my desired project this summer is to see if I can optimize the system to achieve "maximum cooling" I've looked around with multiple searches, and haven't found too much information on what pressures everyone has, and what max cooling vent temps everyone has achieved? I think it would be a great resource to have a thread or a spreadsheet on the variables that different builders have in order to discern some idea of what's possible. Here are mine from memory last summer:

Ambient temp - 75-80 deg
Low - 20psi (+/-)
High 220ish
Vent - 45
28oz of AC fluid in the system
Coyote AC compressor

One of my reasons for this is that we had a cruise night last summer, and after 2 trip down main street, the vents were pouring hot air - which meant the wife was done and wanted out. Yes, it was like 92deg. Yes, I don't think we ever got over about 25mph, so everything was heat soaked. Still seemed like I shouldn't be getting HOT air though!

I've also noted that the system performs noticeably different at low RPMS/idle, than it does above say 2000 RPM. Wondering if a different pulley on the compressor might improve performance? just thinking out of the box....

Thoughts and data/numbers greatly appreciated!

Rian

[PNWTim]

One additional piece of info: Did you use the FF-supplied condenser or go with the Vintage Air unit? Even with a loss of efficiency, I wouldn't think hot air would come into the cabin unless your fan wasn't functioning correctly, but you didn't say you were overheating, so I am assuming it was.

[Kbl7td]

I’ll post up numbers tomo. I’m about to add some dye to see if I have any leaks.

[JimLev]

I’ve got a Vintage Air too.
A few things you could do to make it work better.
If you have more R134a in the system than recommended the pressure will increase above safe limits as the outside temp increases. The hi-pressure switch will shut the compressor off. You then get no cooling. Your high pressure reading was 220 PSI at 75-80. Do you know what it was at 92F?
45F out of the vents is too warm, mine is in the mid 30’s.

I have a 33 hotrod, there were big gaps on both L & R sides by the kick panels. That let in a lot of heat from the engine bay.
Does your radiator fan cycle on/off? If it does you’re not getting enough air past the condenser at those low speeds.
I have my fan running all the time which helps at low driving speeds. I used a PWM speed controller to control the fan speed. If the engine temp sensor wants more cooling the PWM controller is bypassed and the fan runs at 100%.

You have a different car than mine so you may not have all the gaps that I had.
Good luck on staying cool.

[edwardb]

Did something change? The A/C-Heater evaporator unit Factory Five supplied for my Gen 3 Coupe in 2018 (granted 7 years ago) was a Siroco Boreal 600 D65 d16 12V 3V. Rated at 4.45 Kw heating, 3.20 kW cooling. It's a compact unit that just fits in the upper footbox on the passenger side. I've followed several Coupe build threads and all of them looked like the same unit. At the time, I researched multiple other sources, including Vintage Air, and found nothing that fit into the same location. For my Hot Rod Truck build, they were supplying the same setup. Since it had a lot more available room, I was able to fit in a Vintage Air system that frankly worked a lot better. Also a smaller space without the big greenhouse hatch window.

For the Coupe, this is what I recorded in my notes for the first system charge: Gauge readings when done (at 70 degrees F and 24% humidity in garage): Static 84-85 PSI on both low and high. Normal listed as 80-105. While running: Low 18, High 180-250. Low reading seems a bit low, but everything else seems normal. High rises and falls as trinary switch goes on and off, including switching cooling fan on and off. Discharge air temp at vent: 43-44F. Two years ago, it seemed to not be quite as cold. Pressures looked OK but air temp discharge 50-55F. Connected new can of R134A. Seemed to take about 1/2 of the can. Pressures in range for humidity and temp. Discharge air temp at vent around 45F. Test drive and seemed colder.

The Coupe was my first ever A/C install, so I'm far from an expert. My system works "OK." Just had the Coupe out today. Mid-70's out and interior was nice and cool. When it gets into the real summer with 80's and 90's (that's summer for us here in Michigan) it keeps the interior reasonably comfortable but not super cold. I can't explain why you would suddenly get hot temps like that. Doesn't make sense. IMO, somehow the heating portion of the unit starting working. Positive the heater valve didn't open for some reason? My A/C cycles some and is a bit warmer at times, but never close to 92 degrees.

https://thefactoryfiveforum.com/attachment.php?attachmentid=82179&d=1520475416

[Erik W. Treves]

you are using the stock oem coyote AC compressor from a donor??

[PNWTim]

Did something change? The A/C-Heater evaporator unit Factory Five supplied for my Gen 3 Coupe in 2018 (granted 7 years ago) was a Siroco Boreal 600 D65 d16 12V 3V. Rated at 4.45 Kw heating, 3.20 kW cooling. It's a compact unit that just fits in the upper footbox on the passenger side. I've followed several Coupe build threads and all of them looked like the same unit. At the time, I researched multiple other sources, including Vintage Air, and found nothing that fit into the same location. For my Hot Rod Truck build, they were supplying the same setup. Since it had a lot more available room, I was able to fit in a Vintage Air system that frankly worked a lot better. Also a smaller space without the big greenhouse hatch window.

For the Coupe, this is what I recorded in my notes for the first system charge: Gauge readings when done (at 70 degrees F and 24% humidity in garage): Static 84-85 PSI on both low and high. Normal listed as 80-105. While running: Low 18, High 180-250. Low reading seems a bit low, but everything else seems normal. High rises and falls as trinary switch goes on and off, including switching cooling fan on and off. Discharge air temp at vent: 43-44F. Two years ago, it seemed to not be quite as cold. Pressures looked OK but air temp discharge 50-55F. Connected new can of R134A. Seemed to take about 1/2 of the can. Pressures in range for humidity and temp. Discharge air temp at vent around 45F. Test drive and seemed colder.

The Coupe was my first ever A/C install, so I'm far from an expert. My system works "OK." Just had the Coupe out today. Mid-70's out and interior was nice and cool. When it gets into the real summer with 80's and 90's (that's summer for us here in Michigan) it keeps the interior reasonably comfortable but not super cold. I can't explain why you would suddenly get hot temps like that. Doesn't make sense. IMO, somehow the heating portion of the unit starting working. Positive the heater valve didn't open for some reason? My A/C cycles some and is a bit warmer at times, but never close to 92 degrees.

https://thefactoryfiveforum.com/attachment.php?attachmentid=82179&d=1520475416

My unit is a Scirocco. There are a handful of VA parts that came with it but he evaporator unit is the same as yours. I did go ahead and buy the VA condensor as you recommended.

[Rian_Colorado]

Thanks Paul! Great info as always. I did wonder what your vent output temps were. Mid 40's seems to be in line with what mine will do as well, but I would LOVE to get it into the upper 30's. From Jim's response above, it seems like that should be possible. I KNOW I'm not running "too much" 134a - I went to the hassle of buying a postage scale and measured exactly 28oz as recommended by VA. I certainly DO wonder if I could as some more and get a better outcome at the vents...

Just so I didn't confuse anyone - the 92deg that I referenced in my original post was the outside temp that day, not the vent output of the system. I didn't have a thermometer in the car at that time, but the air from the vents was "warm". I also haven't experienced that again since. I've run it a few times here in the spring, and it does run as expected with the mid to upper 40's vent output. I have NOT driven it in "stop and go" traffic like what I referenced above though either.

Erik - Compressor is/was new, on a crate gen 3 Coyote from Forte.

I'm going to hook up the gauges this week and get new numbers now that it's been a year, and see if I'm still in the same range, or if I should add more 134a...

Rian

[Kbl7td]

Mine is about 20 low side. High side fluctuates between 200-300 as compressor kicks on and off. I have a variable displacement compressor that is wired hot based on the trinary. Usually it is controlled by a PWM signal. So not sure if I need to release some 134 or if that’s just how she’ll be because of the variable nature.

[turbodon]

Play with the temp setting. On my previous Vintage Air system, if you went full max cold it would freeze up and then not so cold air. I found that if I did not go past 75% towards max cold the air was super cold and did not freeze up and get warm air.

[Kbl7td]

Can you even mess with the temp setting on the FFR supplied units? I only remember seeing fan control, Ac on/off and then a “temp control” which I believe controls the heater core. If you don’t have the heater core hooked up then AC is max always. For instance I don’t have the heat hooked up here in south Florida.

[edwardb]

Can you even mess with the temp setting on the FFR supplied units? I only remember seeing fan control, Ac on/off and then a “temp control” which I believe controls the heater core. If you don’t have the heater core hooked up then AC is max always. For instance I don’t have the heat hooked up here in south Florida.

I pretty confident that's right. With the FFR system, the temp control is only wired to the heater control valve. A/C happens when the A/C switch is turned on, activating the compressor and cooling the A/C core. Obviously at that point you would want the temp control to the minimum level (counterclockwise on mine). If you wanted less cooling, rotating the temp control would bring heated engine coolant into the heater core, warming some of the cooling air out the vents. It's a pretty basic system. In actual operation, I will say the heater works very well. The A/C I'd give a passing score to, but it's not to the level of most daily drivers. Note also the FFR system doesn't have any doors or valves on the outlets. The fan blows heated/cooled air through all the vents all the time. I've seen where some have added valves into their ducts, e.g. to shut off defrost when not needed for example. Haven't tried that and probably won't. It is what it is.

[sperger72]

Hey all -

I (like many of you) have the Vintage air setup from FFR. One of my desired project this summer is to see if I can optimize the system to achieve "maximum cooling" I've looked around with multiple searches, and haven't found too much information on what pressures everyone has, and what max cooling vent temps everyone has achieved? I think it would be a great resource to have a thread or a spreadsheet on the variables that different builders have in order to discern some idea of what's possible. Here are mine from memory last summer:

Ambient temp - 75-80 deg
Low - 20psi (+/-)
High 220ish
Vent - 45
28oz of AC fluid in the system
Coyote AC compressor

One of my reasons for this is that we had a cruise night last summer, and after 2 trip down main street, the vents were pouring hot air - which meant the wife was done and wanted out. Yes, it was like 92deg. Yes, I don't think we ever got over about 25mph, so everything was heat soaked. Still seemed like I shouldn't be getting HOT air though!

I've also noted that the system performs noticeably different at low RPMS/idle, than it does above say 2000 RPM. Wondering if a different pulley on the compressor might improve performance? just thinking out of the box....

Thoughts and data/numbers greatly appreciated!

Rian

Sounds like the unit needs recalibrated using the whoite wire to ground and making sure that the water valve is fully closed in a/c mode

[JimLev]

My 33 was delivered in 2018.
Looks like Vintage Air has had a few different designs. My box doesn’t look anything like the one shown above.
It has ducts for dash, floor, defrost. One knob let you pick where the air goes. The other 3 are fan speed, AC temp, and heat temp.

213809

[edwardb]

My 33 was delivered in 2018.
Looks like Vintage Air has had a few different designs. My box doesn’t look anything like the one shown above.
It has ducts for dash, floor, defrost. One knob let you pick where the air goes. The other 3 are fan speed, AC temp, and heat temp.


The unit in the pictures above is from Siroco (a French company) as described. Not Vintage Air. It's more compact than anything Vintage Air provides (I've checked) and just fits into the Gen3 Coupe upper RH footbox location. It doesn't have any duct controls as I described earlier. Just all on or off. Seems that FF has standardized on this unit for all their optional A/C setups. Found that to be the case when I wanted to put A/C in my truck build and found it was in the kit for the hot rod and the truck. Looks like the system they're offering for the Gen5 Roadster is also this one. I opted for a Vintage Air Gen II ComPac system in the truck and it fit pretty easily. Had all the duct controls you describe. Worked great. Too bad Vintage Air doesn't offer anything as compact as the Siroco.

Slightly off topic -- some have been following the airplane build I've been doing. Sling TSi with a Rotax 915iS engine. The Rotax has liquid cooled heads so Sling set up the airplane with a Siroco heat exchanger to heat the cabin. Small world. Looks just like the one I have in my Coupe except without A/C. Most smaller GA airplanes use an air-to-air heat exchanger around the exhaust since traditional GA engines don't have liquid cooling.

[JimLev]

How about a plane update and a few pics?

[edwardb]

How about a plane update and a few pics?

Posted a few days ago: https://thefactoryfiveforum.com/showthread.php?48654-My-Sling-TSi-Airplane-Build-Walkaround-Video&p=581397&viewfull=1#post581397

[Rian_Colorado]

So finally had a little more time to look into this with my setup. Here are some video's of what's going on. I'm not sure if I have too much/to little R134? a blockage? or if the condenser is just too darned small? Any input, or comments on how other systems are working compared to this are greatly appreciated!
Garage temp was 75 degrees during the tests....

Vent output gets down to about 45 at the beginning, but drops out to about 60 or so once it's been driven for 5-10 minutes. Stay's in that range even at highway speeds

https://www.youtube.com/watch?v=d7eTUlltPr8

https://www.youtube.com/watch?v=bFqnAhMKXdU

Rian

[PNWTim]

Not an expert by any means but 60 degrees isn't correct by a margin. If you are not sure how much refrigerant is in your system it may be worth it to have it purged and recharged with the precise amount required. This will eliminate that question mark.

[Rian_Colorado]

Not an expert by any means but 60 degrees isn't correct by a margin. If you are not sure how much refrigerant is in your system it may be worth it to have it purged and recharged with the precise amount required. This will eliminate that question mark.

Agreed, and I have an appointment next week to evacuate and recharge just to make sure it's correct. Low side has enough frost on it that I'm worried that it could be freezing up too. The short cycling of the compressor concerns me, especially since the pressures aren't ever out of range enough for that to be happening via the trinary switch? kind of odd behavior?

I know it's not a "factory" AC system, but to me there's no reason that it shouldn't be able to come close to that level of output too. I'm thinking that the condenser is also too small for what the ford compressor is capable of. Looks like vintage air has some larger condensers so I'm wondering about swapping that out too

[Power Surge]

Here's another suggestion that may help. Get yourself some Frosty cool freon. Frosty cool is a company out of Canada that makes 100% organic freons. They're freons run at lower compressor head pressures and produce colder vent temperatures. They have a high performance 134 Freon designed for extremely hot climates. And the best part is 8 oz of Frosty cool 134 replaces 17 oz of regular 134 so don't need as much freon. The stuff is pretty amazing.

[edwardb]

I know it's not a "factory" AC system, but to me there's no reason that it shouldn't be able to come close to that level of output too. I'm thinking that the condenser is also too small for what the ford compressor is capable of. Looks like vintage air has some larger condensers so I'm wondering about swapping that out too

Good luck but that hasn't been my experience with our Gen3 Coupe and the Factory Five heat/A-C system. It works "ok" and keeps the interior comfortable. But it won't freeze us out like the OE system in our SUV. My opinion is probably the relatively small evaporator. Small because that's all that will fit into the available chassis location. It's a Siroco Boreal 600 D65 d16 12V 3V. Rated at 4.45 Kw heating and 3.20 kW cooling. Per Google (my only choice since I'm not remotely an expert) this kW rating is on the low side of what is typical of an OE. Obviously varies depending on size of the vehicle. That big glass hatch and likely less insulation than OE don't help. I'm not unhappy with the setup. I wouldn't want a Coupe without it. But I do wonder how builds in locations warmer than our somewhat mild Michigan weather are doing.

P.S. The heat side works fine. Especially since I also added heated seats. For the A/C, I have my own gauge set and I'm confident it's properly charged.

[burchfieldb]

Anyone ever doing any research on these add on rear AC only systems?

https://www.oldairproducts.com/product/ip-2000t-ac-system

[burchfieldb]

I reached out to Old Air Products and they said this would work for the coupe depending on the size of the compressor. He recommended a Sanden 709 heavy duty compressor and said a second drier would be needed. Just need to get the unit dimensions from them to see where it might fit. Possibly in the area over the rear wheel in the side panel.

[Rian_Colorado]

Just updating this thread for those following.

So I had a shop that I trust (owned by a friend of mine) Vac out and re-charge the system.

First go, they installed what Vintage air lists as the appropriate value of freon (28oz). I had done this when I charged the system as well using a mail scale. The results were pretty much the same as what I have been getting.

Next they vac'd it again, pulled a vacuum for longer, and then charged with 22oz. Much improved, but still showed signs of overcharge.

So they did it a 3rd time, and filled with 19oz. (final result)

Now the system blows the coldest that it has, and seems to continue to blow cold over time. I drove it around for probably 20 mins yesterday, and it never got "warmer" as it has in the past. Granted, it was only 85 degrees, and that's not really a LONG drive to get things very hot. I have not yet hooked it up to gauges in the shop to see what that shows, but I'll try to do that in the coming weeks. I do have an event coming up that will test the system a lot more, so I'll report back after that.

Long story short, I'm feeling confident that 28oz it far too much for the system as designed. Even the stock Ford mustang system (ie the same compressor) lists 21oz of freon as the correct fill. Taken with Pauls info about the evaporator being smaller than normal (I've not found ANY data on size or capacity of the one in a mustang) I would guess that the correct fill should be at OR LESS than the mustang freon requirement.

Long story short, if I was re-filling the system myself again, I would start at say 15oz, and slowly work my way up from there (and not exceeding 22oz).

I'm still considering adding a larger condenser unit, and maybe a different fan. (I'll likely copy what others have done with the Flex-A-Lite fan - I'm already using one on my 427 mk4 project). That'll be a fall or winter project though

Rian

[Smiley]

Do they provide you with any target superheat or sub-cooling numbers?

[Namrups]

When I had mine refilled recently they said that they added 2 lbs to get the pressures where they needed to be. That would be 32 oz's. I guess I need to look at this a little more.