A/C charging issue resolved.

[brokencase]

You (Dean) wrote above to lubricate lightly the panel vent thumb adjuster as it seemed stiff/sticky.

That's not desirable for a simple reason: with the blower set on High air force inevitably moves the vents to horizontal positions from whatever they previously were set to (in A/C likely upward tilted to maximize cooling effect on occupants).

Your printed panel vent adjusters need some to move with some friction or they will return quickly to horizontal settings when blower is on High.

YMMV

I was speaking of the side to side vent adjusters. If I close mine all the way to the side, it can be difficult to open the vents up again.

My 3d printed "high flow vents" have friction up and down like the originals.

[brokencase]

Project Farm tests R134a against R134a substitutes:
.
https://youtu.be/41HBPqdMxfI?si=dm_mEJI7dtNdFWdt

I wouldn't be satisfied getting ~45* vent temps driving 55 mph. Although, Todd doesn't say if those 55 mph testing excursions were short distances, say a mile or two/three.
.
YMMV

Good video Ed. Mainly because he shows proper techniques in recovery, line purging, etc...

However once again you are making too much of vent temperatures. 40-45F is fine. I think the Helms manual states as much for the Scorpio.
On a hot day you're never going to get the cabin temperature down to the vent temperature anyway. As I stated earlier, perceived coolness is more about the volume of air blowing over you. In addition, pulling the cabin temperature down is more a function of the volume of air you can recirculate through the evaporator than it is about the ultimate low temp of the evaporator.

I should check to see what the vent temps are in my 2019 Ranger.

I would have anticipated better performance with the hydrocarbon based refrigerants. I wonder if he was being too conservative with the amount of refringent he used in those cases. It didn't look like he added enough. Data elsewhere (and my own experience with my previous Scorpio) indicated that hydrocarbon replacements for R12 equaled or outperformed R12. It would be interesting to know what the composition of the stuff he tested was.

The flammability risk is an over-reaction. As I believe we spoke of previously, the future replacement for R134a will be hydrocarbon based and flammable.

[brokencase]

I just took the Ranger out for some errands. It is 98F outside.

I drove into town (about 2.5 miles) to the post office, and from there I then took a about a 5 mile drive to a grocery store down a 4 lane where I was doing about 45-50mph.

The lowest vent temp I saw was about 55F. This is with MAX A/C recirculating all vents open and full speed fan.

However, comfort level was way beyond what is experienced in the Scorpio under similar circumstances, even though the vent temps on the Scorpio are much lower.

I'll have to look at the Ranger manual and see what is expected. It is possible that after 5 years it might need a refrigerant top off, but it is still way more comfortable than the Scorpio and this I attribute to the fact that it moves so much more air through the vents.

[Ed Lijewski]

I just took the Ranger out for some errands. It is 98F outside.

I drove into town (about 2.5 miles) to the post office, and from there I then took a about a 5 mile drive to a grocery store down a 4 lane where I was doing about 45-50mph.

The lowest vent temp I saw was about 55F. This is with MAX A/C recirculating all vents open and full speed fan.

However, comfort level was way beyond what is experienced in the Scorpio under similar circumstances, even though the vent temps on the Scorpio are much lower.

I'll have to look at the Ranger manual and see what is expected. It is possible that after 5 years it might need a refrigerant top off, but it is still way more comfortable than the Scorpio and this I attribute to the fact that it moves so much more air through the vents.

The Scorpio cabin volume likely is ~50%+ greater than your Ranger (which I assume is a two door possibly with storage area in back of seats) as a/c cool has to mix with the Scorpio rear shelf and some trunk air which isn't sealed from the cabin.

Also I bet your Ranger has dash vents placed higher than the Scorpio center vents; cool air from higher placed vents has a substantially greater sensual effect on passengers even with both blowers on High.

This morning @ 8 a.m. with temp ~ + 80* in my '89 I went to H.D. driving 65 mph for ~7 miles, RECIRC On, EATC at 60*, blower on High. The cabin got COLD. And for a reason I don't yet understand 30 minutes later the return trip with the same settings felt COLDER, so I measured center vent temps which read 27*. Yes, the de-icing switch works fine (I cracked the sunroof at that point to bleed off some 27* cold air).

No two bodies are likely the same. For me only a/c vent air ~ lower 30*s on 80*-90*-100* outside temps days cools me to a cabin comfort level. Your mileage may vary.

My '88 Scorpio is charged with R12. It cools really well.

I had charged my '89 with R12 but after losing three successive R12 charges (expansion valve O-ring leak; compressor hose failure; compressor bearing failing) I decided to hold on to my remaining R12 stock while trying DuraCool 12a (butane and ethane blend) since June 2023. FYI, DuraCool 12a is far more "efficient" than R134a as much less DuraCool 12a by volume is required.

YMMV

[brokencase]

The Ranger cabin is a little smaller than that of the Scorpio (it is the crew cab), but glass area is less.
In addition, the rear and back windows are tinted fairly dark from the factory.

However the seats are cloth as opposed to leather in the Scorpio...which is where the real divergence lies.

The Ranger is comfortably cool. It's not the height of the vents. It's the amount of air blowing out of them.

But this little experiment makes me think that the Ranger might be a little low on refrigerant. I expected to see lower vent temperatures. I will add a little and see if it makes an improvement. I could not find anything about A/C in the digital manual that I have.

Prior to the Ranger I had an Explorer Sport Trac. The condenser failed on that at around 100k miles. It was not well shock mounted on the lower corners. Repair was easy despite the fact that the radiator had to be removed. I think the new condenser was about $75.

The A/C on that vehicle was also exceptionally good.

[Ed Lijewski]

However once again you are making too much of vent temperatures. 40-45F is fine.

.
Open your standard refrigerator (freezer on top) door and hold your head close to the racks. The temp there feels...not warm but also not very cool.
.

It's not the height of the vents. It's the amount of air blowing out of them

.
Open the freezer section and hold your head near the contents. You immediately sense coolness, more so if the freezer fan, which doesn't move a large volume of air, is operating.

This demonstrates how very low car a/c vent temps, without or with low fan operating, directed at upper torso/head level, produce a large effective cooling sensation on a body.

A/C air from high-placed center vents has a faster cooling effect. And that cold air falls over the lower sections of a body.

YMMV

[brokencase]

That all might mean something Ed, but we are only talking about a few degrees difference of say, 45F vs. 38F. Lets take these vent temps as an example.

When you first sit down into a Scorpio that has been sitting in the sun and the seats are 120F you will not perceive the difference.

First off the air exiting the vents almost instantly entrains the surrounding cabin air and mixes with it, even across that short distance from the vent to your body. So at this point it is really only the breeze that you are perceiving.

Secondly, when you first get into the Scorpio with 120F seats, you don't have 38F vent temperatures. It takes a long while before those vent temperatures come down to 38F. If it is really hot out you may never see that ultimate 38F (of 45F) vent temperature.

So, the only thing that is going to bring down the cabin temperature more quickly (along with the vent temperatures) is recirculating a larger volume of air through the evaporator. Opening up the vents, increasing air flow through the vents, bigger fan, faster fan, more efficient fan, etc... These items will also increase your perception of coolness by providing a bigger breeze out of the vents.

So, for example, you get into your hot Scorpio and turn on the A/C. At first you get 100F air coming out of the vents. Out it goes into the cabin and then gets sucked back in through the recirculation inlet. Now it comes out at 99F....around it goes again and out comes at 98F...round again and out comes 97F etc... The only thing that will make this loop operate more quickly is a larger flow of air.

The important point is this. On a hot day you're never going to get your Scorpio cabin temperature to come down to your ultimate low vent temperature, be it 38F or 45F. The A/C system is constantly fighting against the beating sunlight and the warm ambient outside air.

Indeed if we were able to make such modifications that increased flow through the system we may actually loose our previous obtainable 38F vent temperature because we are now burdening the evaporator to do more work by pushing more warm air through it. It could be the case that after these mods we now see 45F at the vents. But this is OK because in doing these changes we know that we are now lowering the cabin temperature more quickly.

[Ed Lijewski]

* With a sun-heated interior one should first open and swing a front and rear door a few times to remove some heat load.

* Then start the engine putting the blower on High in either RECIRC or Outside mode for several seconds, with driver's door still open.

* Crack open sun roof.

* Then close door and set blower to Low in RECIRC and move along on road as compressor irefrigeration cycles increase with higher engine speed.

* Close sun roof after 2-3- minutes.

* Vent air temp will become degrees lower more quickly than if blower is on High. And then that vent air if/when directed towards the driver (or passenger) will produce an earlier beginning cooling effect.

* After 2-3-4 minutes underway the blower can be set to High in RECIRC.

The objective above is not to quickly lower cabin average temp. The objective is to achieve maximun effective benefit from early evaporator air cooling directed on the driver (passenger). Try it if you doubt its effectiveness.

* Inhaled cool vent air arriving directly at the driver (passenger) enhances the sense of body temperature being reduced.

* I love Raven leather (and Biscuit as well) but from late spring through to early fall I cover both front seats with large black bath towels. I choose black ones as that looks nice with a Raven interior. These towels both protect the Raven leather and their terry cloth doesn't retain solar heat through windows. A plus is the towel thickness feels pleasant sitting on them.

YMMV

[brokencase]

Understood, but my point is you can't use "ultimate low vent temperature" as an A/C performance metric across different Scorpios.
It is even difficult to use it as a "target goal" when tweaking your own A/C system.

There are too many variables involved.

For example you might have dog hair clogging the inlet of your evaporator and the other Scorpio does not.
You see 38F vent temps (because the air moves more slowly through your evaporator)
The other Scorpio sees 42F vent temps (because he is moving more air through the evaporator)

Clearly the other guy's Scorpio A/C system is operating better than yours.

Even the above comparison can only be made if the two vehicles are under similar ambient conditions, which is highly unlikely.

The only real metric one could use (under the same ambient conditions) is to plot cabin temperature over time since startup.

Anyhow, this is why proper vent temperatures are stated as a range.

[brokencase]

I just realized the Ranger is using the new 1234 stupid expensive refrigerant. It's like $50 dollars a can.

Also the 55F vent temperature I am reading in the Ranger is about what is expected for the high ambient temp and humidity that we are currently experiencing. And you know what? The Ranger is comfortably cool.

But I must admit the Scorpio vent temps run cooler under the same circumstance. Too bad the Scorpio fan/ducts do not move enough air.

Which again re-enforces my earlier argument that it is not all about vent temperatures.

[Ed Lijewski]

My experience with a/c makes me detest the EATC's blower control. Specifically that with the Temp setting at 60* (full cool), coolant flow through heater shut off, there is no Medium blower setting, only Low and High.

High blower a/c is useful at most for short periods, single digit minutes typically, to circulate (RECIRC) hot/humid air from the front of the cabin. Any longer and the sound and rushing air is objectionable.

Then I'd really like to be able to access Medium blower speed but that requires resetting Temp to 61* or above at which the EATC opens coolant flow through the heater core. Coolant flow is either On or Off, not modulated to Temp settings (the EATC adjusts the blend door not vacuum to the heater control valve).

So I then mostly use Low blower setting which generates cool/cold temp air okay for situations with vehicle moving along. But in general I know other situations the a/c air would provide better cooled comfort with the blower on Medium setting.

All of this would be just an academic exercise if not for ambient temps as high as they've been so often this year making it necessary to get as much cooling effect as possible from the a/c system.

You or others might think and say coolant flow through the heater core makes little if any difference You and they might not notice any difference; I can and do, in both XRs and Scorpios.

Sorry to hear about your 1234y (IIRC) price; that pinches.

YMMV

[brokencase]

Well, I must say that right now is the best the Scorpio's A/C system has ever performed.

Removing the problematic vent doors is a big part of it (for which I thank you).

But I think my 3d printed exit vents are "less noisy" at the hi fan setting. Which I think equates to more flow as well.
I should do a sound measurement to compare with the old exit vents.

I have a sound analysis program that runs on my laptop that can allow me to do that. I used it to set up the crossovers in the speakers in my home audio system. It has a spectrum display.

That is an experiment I can easily do.

[Ed Lijewski]

Glad to know that.

FWIW when I removed the dash covers (on four) Scorpios) to get at the vent motors or for other reasons I noted that the blower hoses to vents did not each seal tightly on the vents.

IOW there's possible (probable) leakage at one or more hose-to-vent joint. The molded hose ends are just friction connected but they aren't always perfectly matched to the vents. I think strapping them with Zip Ties likely would be worth the effort which wouldn't be great.

YMMV

[Ed Lijewski]

Use a Chillgo air conditioner to augment your car or truck a/c comfort delivery:
.
.https://youtu.be/Me7PCj8KAPM?si=WhsYJ7e0Jzd9fnY0

YMMV

[brokencase]

Yeah, I'll rig "mist" sprayers in the air con vents.

I think the Farm Project guy is running out of things to review...