A/C Reverse The Gases in Early Model 911's

[KelogGes]

If you want to "reverse the gases" and test my claim ON an early model 911

INSTALL THE DESCRIBED HOSE MODIFICATIONS PROPERLY; DOUBLE CHECK EVERYTHING IS PROPERLY INSTALLED

When you Turn the a/c on only use the lowest evaporator motor blower speed settings!!!
LOW SPEED VENT BLOWER MAKES THE AIR COMING OUT OF THE AIR VENTS COLDEST!!!


you should have the front blower turned on and working, use water to cool the front condenser
IF YOUR 911 is not moving and/or you do not have a front condenser blower!



"Get or USE A long shaft DIGITAL Thermometer", like that is used in cooking and put it deep into the cab air-vent output; i.e. digital meat thermometer ; put the long shaft into the a/c vent in the cab as far back as possible “into the airflow”
(DO NOT use an infrared gun or similar !!!!)

Close the windows and doors and the smugglers box cover and latch it

ATTACH THE GAUGES AND HOSE CONNECTED TO your 911 high and low sides, and THE R134A refrigerant canister; TURN ON THE R134A canister VALVE WITH THE VALVES ON THE GAUGE SET CLOSED (turned off)!!!



Run the 911 engine at a constant 2000 Rpm, with the deck lid CLOSED OR near closed, this allows the engine fan to suck FRESH outside air through the rear condenser from outside of the engine compartment

I use a PRO ROBINAIR Automotive R134A certified machine, but I don’t expect you as a DYI to have one, but I also have a professional set of R134A automotive gauges I also use to dial in exact refrigerant amounts and test gases


Before you Start with filling R134A gas on a 911 for this test USE a real PRO SET of a/c calibrated for R134A gauge set with multiple valves and hoses on both the high and low sides and refrigerant canister (3 HOSES WITH 3 VALVES) , (not the gauge on a can type) and make sure to also use an accurate weight scale underneath the canister ! Harbor Freight OR CHINESE Gauge Sets SUCK AND ARE NOT ACCURATE AND/OR NOT CALIBRATED ACCURATELY DON’T USE THEM FOR THIS TEST
For only a few bucks Rent a professional-set of R134A gauges, if you don’t have or can’t borrow good ones and with good connection ends that do not leak !

Something to know/understand about R134A

for many years I have worked on large yachts and various maritime vessels that were/are completely self-contained, in marine engineering
Over the years I have interacted and talked to many refrigeration, A/C and refrigerator/freezer technicians and other related engineers

The consensuses is all these refrigeration types of systems make the coldest temperatures possible for the amount of refrigerant used when they are running on the very least amount of refrigerant possible when the system runs @ optimal peak performance, and does not leak ANY refrigerant as told to me and also has been my experience.

regardless

R134A has a very tight envelope TO MAKE COLD of “just a few ounces”; and either side of this envelope OF only a few ounces for optimum performance PLUS THE ADDING OF ADDITIONAL; OR MINUS NOT ENOUGH amount of gas; “ makes cold hotter” !

People have a tendency to overfill R134A gas all the time thinking it’s better to top off the system with extra, like you can do with say R-12 freon, because R-12 is very forgiving refrigerant with a wide envelope window; This IS a major mistake committed by many, including so called technicians. Most People don't read and/or fully understand the technical literature R134A they just use it without knowing its technical properties !

R134A IS A VERY PICKY REFRIGERANT! USE THE LEAST AMOUNT POSSIBLE TO MAKE THE COLDEST LOWEST TEMPERATURE!!!!!


FYI as an example MY PFC CONDENSERS USE SLIGHTLY LESS THAN A POUND OF R134A for optimum peak performance in a 911 a/c system and “You Do Not Have These” therefore you’re going to need more gas than one pound,

Start with the minimum amount of gas using only one pound of R134A (16 OUNCES) for the START OF THE TEST; and carefully add only one ounce R134A at a time in steps using a small scale TO WEIGH THE GAS IN ITS CONTAINER, ADDING ONLY ONE OUNCE AT A TIME; noting the low side pressure gauge and the scale to know exactly how much R134A gas AND LET IT BALANCE FOR A FEW MOMENTS/OR MINUTES BEFORE YOU DECIDE TO ADD MORE! AND MAKE SURE YOU WRITE EVERYTHING DOWN FOR EACH OUNCE AFTER IT IS ADDED AND THE SYSTEM BALANCES!

Do this when the outside ambient air temperature is not rising or falling, say in the morning or at night when ambient temperature does not change much!

With the 911 running at 2000 RPM
ADD
step by one ounce step COLDER
step by one ounce step COLDER
step by one ounce step COLDER
step by one ounce step COLDER
step by one ounce step COLDEST!!!!!!!!
UNTILL YOU GET THE FIRST SLIGHT TEMPERATURE RISE WARMER THIS INDICATES YOU ADDED TOO MUCH GAS BY ONE OUNCE!!!!

THEN REDUCE BY ONE OUNCE OF GAS BY WEIGHT AND THIS IS YOUR EXACT WEIGHT OF R134A (memorize this ounces number and also write it down to keep)
YOUR minimum optimal peak performance amount of R134A IN OUNCES YOUR CONDENSERS AND A/C SYSTEM NEED IS NOW KNOWN EXACTLY FOR YOUR 911

OR REFILL YOUR A/C SYSTEM to this exact number of ounces you now know is the

And remains always true until you modify or replace any a/c component you have in your system differently

OR REFILL YOUR A/C SYSTEM with your newly discovered exact minimum optimal peak performance amount of R134A

until you know the minimum optimal peak performance amount of R134A YOUR CONDENSERS NEED FOR THIS TEST BY EXACT R134A WEIGHT !

ONCE THIS IS SET EXACTLY, you can now properly TEST MY “REVERSING THE GASES” test driving, and at different times of day, when the sun shines, etc, etc,,, WITH THE DIGITAL TEMPERATURE cooking/food THERMOMETER

YOU CAN USE A use an infrared gun or similar !!!!)
TO SPOT TEST ENGINE OIL TEMPS INSIDE THE DECKLID ON THE ENGINE, AND CONDENSER METAL TEMPS; BUT IT CANT READ AIR TEMPS IN THE AIR

[monkeyodeath]

Totally amazing how any A/C related topic on this board immediately descends into something resembling religious zealotry -- complete with riddles, revelations, and keys to mystical knowledge.

This about a technology that's been in cars for more than 50 years.

Are people suffering from heat stroke/exhaustion as they participate in these threads?

[KelogGes]

This works better than you can imagine

TEST IT AND YOU WILL SEE FOR YOURSELF

[wwest]

Originally Posted by KelogGes

This works better than you can imagine

TEST IT AND YOU WILL SEE FOR YOURSELF

Again, the numbers indicate that the rear lid condenser is 240% more effective for heat transfer vs the front lip condenser

Even so, KeloGes' reverse flow system will work, just not any better, and quite possibly worse, than the factory system.

The proof in the pudding would only be attained by measuring the cabin temperature "pull-down" time with the factory system vs the "reverse flow" technique.

KeloGes' system will work as represented using JUST the front condenser given the closed up cabin and enough time.

[Ronnie's.930]

Bob,

What do you think of this Stemme classic? I likey!

[stormcrow]

Based on the design this is what's going on. The compressor is pumping refrigerant liquid to the front of the vehicle. The tubing under the vehicle is acting as a condenser and is being cooled along with the refrigerant in the front condenser.

Once the liquid refrigerant leaves the front condenser it is returned to the rear condenser on the inlet side and circulates through the rear condenser at a lower temperature. From there it exits and goes through the filter dryer and then on to the expansion valve.

Now this makes perfect sense for more cooling capacity because the efficiency has been brought up. sort of like going from a 10 Seer condensing unit to a 14 Seer condensing unit.

For those of you who aren't aware the condensing unit on the 10 Seer is much smaller then on the 14 Seer condensing unit.

So that being the case with this change in refrigeration flow design, you are actually increasing the Seer rating by increasing the liquid line capacity.

So as a result your pressure at the evaporator will be lower and it will cause the evaporator temperature to be lower.

But there is a catch. If the temp on the evaporator is at 30F then you are going to have a freezing problem. The temperature cutoff switch on the Porsche A/C is around 40 - 45 F to keep the coil from freezing.

If the temperature is at 30f then the A/C compressor is going to short cycle. - it won't happen immediately when the vehicle cabin is at 100 F but as soon as it cools down with the greater TD the temperature drop will cause the compressor to short cycle.

Now if the Heat load on the Evaporator remains high all the time then there is no problem. But without keeping the TD between the evaporator temperature and the cabin temperature constant - like 68F then the evaporator temp will continue to drop and the unit will start to short cycle.

I think this is the way KeloGes was talking about the change in design of the system. It would be more efficient no doubt but with there lower evaporator temps there could be issues down the road.

Hope this makes sense for everyone to understand. KelolGes, if I am wrong about the way I described the system sequence by all means step in and make any corrections.

[SilberUrS6]

Originally Posted by GH85Carrera

This is like A/C comedy gold. Those two arguing about AC.

It is much like the old Saturday Night Live skit were a bunch of men sat around and discussed "Women's Problems"

Next up a 12 year old boy singing the Frank Sinatra classic "My Way"

Pure comedy.

^^^this

All we need now is a clip of South Park. "Cripple fight!"

[SilberUrS6]

Originally Posted by monkeyodeath

Totally amazing how any A/C related topic on this board immediately descends into something resembling religious zealotry -- complete with riddles, revelations, and keys to mystical knowledge.

This about a technology that's been in cars for more than 50 years.

Are people suffering from heat stroke/exhaustion as they participate in these threads?

Naw, just a couple of fools, who are bad at math and science, trying to sell stuff.

One does it by pretending he has data, but never presents it. The other by pretending he has product, but then never sells any, all the while calling the tech forum members names.

Just about ANYONE else in the tech forum can give you good info about how to improve your AC in cars never meant for it. Heck, some of these guys have done REALLY great work in getting excellent performance out of this marginal design.

But here is the ultimate truth: There is no quick fix for getting the AC in your 911 cool. No cheap and easy bolt-on solution. It just isn't there. All those who claim it is there are lying, because after all this time, not one of them have provided any data.

[Ronnie's.930]

^^^

[SilberUrS6]

Originally Posted by Ronnie's.930

^^^

Yup. Reid and Willard. Now, to mix our metaphors, which one will go full-retard first? My money is on Reid.

[stormcrow]

You can improve the efficiency to some degree - Griffiths I believe has a condensing unit you can install. But it is designed to work with the system to make it more efficient.

Going back to what I stated about the temperature drop. If you cool the liquid refrigerant too much then you have less of a pressure differential at the evaporator. Instead of a gas being pushed through the evaporator to absorb the heat, you now have a liquid.

Sure it will be cold but then again the system is not doing what it was designed to do. You are correct there is no easy fix but the fix that you can do is very expensive.

[KelogGes]

Originally Posted by stormcrow

you can improve the efficiency to some degree –

Going back to what i stated about the temperature drop. If you cool the liquid refrigerant too much then you have less of a pressure differential at the evaporator. Instead of a gas being pushed through the evaporator to absorb the heat, you now have a liquid.

Sure it will be cold but then again the system is not doing what it was designed to do. You are correct there is no easy fix but the fix that you can do is very expensive.

interesting comments but your COMPLETELY miSsing the big picture

Forget I am using new technology PFC condensers I make and getting very cold temperatures due to my pfc's

And NO your thinking is wrong about the refrigerant lines are doing anything related to heat exchange transfer; other than transporting the gases and your thinking about the gases in the evaporator is not pertinent either

think about what is going on with the reversed gas flows from the way they have always been, to this completely different way than they have ever been and how they would work on any kind of condenser technology used and the benefits even on old OEM tube and fin technology etc

Porsche engineers made a major FU among many with the "just thrown in" early model 911 a/c system; this is about their routing the gases backward blunder I discovered 2 years ago and decided to finaly tell the 911 ownes and the world about it recently the other day.

I have a couple of pelican 911 owners who have used my clues and are getting IT and figuring out my very easy clues

someone or2 that is a DIY'er will make a test soon that will coost them test hoses and gas etc and prove my discovery is not BS related to refersing the gases, its now only a matter of time

what you read today is me giving more information to help them so when they test this it will be a good one



for others they can keep scratching their heads siting in the corner!

I have given more than Adequate clues for anyone who uses their brains to think

[DaveMcKenz]

Hi Reid,
Thanks for the detailed post on how to charge a nonstandard a/c system. Since you have clearly gone through this process many times, maybe you could publish here your data for the Black Swan, stock vs. reversed, vent temp values, charge weight at each additional ounce, etc. I am sure you meticulously kept all variables the same and recorded your results when you first verified your reversed system, and that data would certainly help quiet the naysayers here.
Let's not forget, that many wonderful inventions were advances long before anyone knew exactly why they worked so well. I also understand that you have no "burden of proof" whatsoever. I really don't understand why people feel so strongly in their opinions of what would and wouldn't work, without testing it themselves. Maybe your data would trump their theoretical speculations. I, personally am at the stage of thinking "huh. that might work. let's see the data."
Thanks,
Dave

[SilberUrS6]

Originally Posted by DaveMcKenz

I also understand that you have no "burden of proof" whatsoever.[...] I, personally am at the stage of thinking "huh. that might work. let's see the data."

Dave, do you see how the sentences I have quoted are at odds?

That's just the issue. Lots of claims made, a miracle in the making, move to this new design for modern Japanese sedan levels of comfort...

In a tech forum, folks want more than ad copy. Repeated ad copy is silly in the face of repeated requests for more details. Even requests for product, requests for beta testing, etc. When none of that is forthcoming, then what are you left with? Hot air (pun intended.)

At first, I was intrigued by the possibility, and wanted to buy product. But repeated requests for info and pricing were met with utter silence. I wasn't asking for technical specs on performance, nor construction or design specifics. I wanted to know what was included with the condensers and how much they cost. You know, in order to compare with the other aftermarket producers. Finally, after six months of going nowhere, it became clear that it's just a lot of talk. Reid often takes offense at anyone who dares ask him to show even a tiny bit of evidence for his claims. Not proof, mind you - evidence. He provides zero technical details, and just repeatedly makes claims. Maybe he's of the school that thinks there is no such thing as bad publicity? I dunno - I don't think that particular method worked very well with MotorMeister. I doubt seriously Reid is going to overcome his obvious disdain for his customer base.

With all the folks here who have taken the proven route and gotten good results, why would anyone take a chance on a guy who makes a lot of claims and provides nothing to back them? If you want to sell product, you have to show folks why your product is better than the other guys'. Or how your solution works better than the way that it was done before. People will buy your stuff. Fred Cook's fuse panel? Kirk tool for valve adjustment? Len's fuel lines? Just as examples.

And finally, berating your potential customers is a sure way to send them to your competitor, even if your competitor has inferior product.

[DaveMcKenz]

Thanks Eric,
I completely agree with you. Those two quoted phrases should be connected by an implied "but". I was hoping that Reid would move away from the arguments, and provide data to silence the speculators. It's up to him. I think there are better ways to present ideas and products, but I hate to discard what may be beneficial.
Dave

[SilberUrS6]

Originally Posted by DaveMcKenz

Thanks Eric,
I completely agree with you. Those two quoted phrases should be connected by an implied "but". I was hoping that Reid would move away from the arguments, and provide data to silence the speculators. It's up to him. I think there are better ways to present ideas and products, but I hate to discard what may be beneficial.
Dave

Absolutely. When you make a claim, you have to show something in order for folks to see it's not merely talk. Talk is cheap, and on the internet, words are worth exactly the PP monthly subscription price.

"Hey guys, this is what I have. It installs in place of these parts, and costs this much. Here is the before testing results, and here is what I got after doing these changes." If questions or criticisms come up along the way, you answer them as best you can, with hard data if possible.

It's not difficult. And it's not like this approach is ground-breaking, LOL.

[KelogGes]

Originally Posted by DaveMcKenz

Hi Reid,
Thanks for the detailed post on how to charge a nonstandard a/c system. Since you have clearly gone through this process many times, maybe you could publish here your data for the Black Swan, stock vs. reversed, vent temp values, charge weight at each additional ounce, etc. I am sure you meticulously kept all variables the same and recorded your results when you first verified your reversed system, and that data would certainly help quiet the naysayers here.
Let's not forget, that many wonderful inventions were advances long before anyone knew exactly why they worked so well. I also understand that you have no "burden of proof" whatsoever. I really don't understand why people feel so strongly in their opinions of what would and wouldn't work, without testing it themselves. Maybe your data would trump their theoretical speculations. I, personally am at the stage of thinking "huh. that might work. let's see the data."
Thanks,
Dave

Howdy Dave
You’re one of people starting to seriously get this actually thinking with your mind.
GOOD FOR YOU!

The rest with their drivel haven’t a clue, or have an agenda, they just post and flame me and fill up the tread with BS! Which is typical here the cause of every A/C thread ruined I don’t even go in too.

However I have a couple of other 911 DIY owners farther along then you in their thinking and this is why I POSTED and explained in detail about R134A and charging with the least amount possible with R134A when they are ready and for others who don’t know how to charge their A/C system with stock OEM components or modified to find their exact amount of R134A in ounces NUMBER for their particular 911.

Regarding the DATA you mentioned on THE BLACK SWAN!


THE BLACK SWAN has a matched set of my front and rear Parallel Flow Micro Channel Condensers (PFC’s) new technology designs on it!
No one you know or have talked to at this time has my PFC’s that were specifically designed for and made for early model 911s!

Therefore giving you any of THE BLACK SWAN data is kind of useless as it would completely Skew your objectivity

I don’t work with stock early model 911’s A/C;s anymore and have not for a long time
I am only into my state of the art PFC’s and other New Technology A/C early model 911 components and designs

You need to test this on a much less exotic 911 than THE BLACK SWAN A/C IS for data!

i.e. a stock factory OEM early model 911 A/C system, any year from say 1970-1989 that has front and rear condensers, OR?
Your 911 or a friends

THIS DISCOVERY WORKS for all early model 911's even modified ones

[stormcrow]

KeloGes

Ok so you are using parallel flow condensers - I understand that but you didn't say that those needed to be installed for more efficiency.

What I detailed is based on what you were talking about with regard to liquid refrigeration circulation. The way you explained it was exactly as I described.

Now you mention the Parallel flow condensers. But you are not addressing the issue which is a freezing coil. 30F is freezing and once the cabin becomes comfortable you normally have a 30 degree TD.

So if the cabin is at 70F the evaporator is around 40 F. However if you increase the TD then the coil is going to start to freeze.

So your design with the parallel flow condensers may be creating more efficiency but too much efficiency causes other problems of an already designed system.

I am not in dispute of your claim for a better system based on your parallel flow condensers - that's great. But again unless the evaporator coil is also designed for these changes there will be issues with TD between the cabin temperature and the Evaporator coil temperature.

Just saying - can you address that issue and how you solved it.

[DaveMcKenz]

Thanks Reid,
My request for data was based on the day that you first tried your reverse flow arrangement. Whatever car you used, with whatever equipment, you may have measured some vent temps before and after you reversed the flow. Maybe you did not record the temps at the time, and I would understand. Sometimes I make a change that is so obviously for the better, that I forget to take before and after measurement.
Dave

[911pcars]

Originally Posted by stormcrow

KeloGes

Ok so you are using parallel flow condensers - I understand that but you didn't say that those needed to be installed for more efficiency.

What I detailed is based on what you were talking about with regard to liquid refrigeration circulation. The way you explained it was exactly as I described.

Now you mention the Parallel flow condensers. But you are not addressing the issue which is a freezing coil. 30F is freezing and once the cabin becomes comfortable you normally have a 30 degree TD.

So if the cabin is at 70F the evaporator is around 40 F. However if you increase the TD then the coil is going to start to freeze.

So your design with the parallel flow condensers may be creating more efficiency but too much efficiency causes other problems of an already designed system.

I am not in dispute of your claim for a better system based on your parallel flow condensers - that's great. But again unless the evaporator coil is also designed for these changes there will be issues with TD between the cabin temperature and the Evaporator coil temperature.

Just saying - can you address that issue and how you solved it.

The expansion valve sensing bulb determines refrigerant flow into the evaporator. If evap. temps go below a certain threshold, the expansion valve restricts refrigerant flow to avoid evaporator freezing. The exp. valve does this independently of the system's ability to operate at whatever level of efficiency.
https://macsworldwide.wordpress.com/2010/07/14/your-car%E2%80%99s-expansion-valves-and-orifice-tubes-keep-your-ac-flowing/

A/C systems can also employ temp. sensors to automatically de-energize the compressor to produce the same effect (reduce/restrict refrigerant flow through the evaporator).

Sherwood