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Thermal Dispersant on an AC condenser - for the Dodge.

WarWagon

Well it hits on 7 of 8...
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I didn't really find an article that connected the dots until the 'Thermal Dispersant on a heater core' came up. :stop: Wait, What!? o_O

Thermal Dispersant on a condenser will improve it's efficiency by up to 33%? :jawdrop:

It was 107 yesterday and the rains moved in Friday rendering "It's a dry heat" null and void.

New condenser is in the mail to be coated... I'll take ANY improvement!

So looking at my favorite trouble spots, automotive AC, I choose to start out with one I can monitor the head pressure and fan speed on. No, not the one giving me trouble - they ALL do. Trouble is the system literally blowing up like you see in the youtube tests as Patch blows out the high side sealing washer on the compressor hose and the Dodge pops the relief valve at 450+ Psig. The Dodge ECM doesn't kick out the AC clutch due to a bug thus it will pop the relief 2x or more per year and dump 1/2 the system charge aka 1 LB. I don't expect it to cure the bug as the second part is not enough fan.

What I would like to see is once I get the fan spinning and let it idle is lower head pressures. On fan speed 3 I will see 350-400+ Psig idling. Speed 4 is asking for it to pass 400 Psig even with ~1400 RPM on the fan at engine idle.

I have a crew cab, but, the Mega Cab's have the same size AC system and it's way undersized for it. IMO coating both the evaporator and condenser may help the undersized system out to cool down that "School Bus" Megacab.

Here is the data readout I will use. It's showing 454Psig max peak on a cold start. (The current reading Psig is the AC shut off as it was running away fast.) I have since added fan commanded % and Fan RPM. This is condenser overheating due to no fan RPM. I don't expect this to be cured.

454psi.jpg
 
I didn't really find an article that connected the dots until the 'Thermal Dispersant on a heater core' came up. :stop: Wait, What!? o_O

Thermal Dispersant on a condenser will improve it's efficiency by up to 33%? :jawdrop:

It was 107 yesterday and the rains moved in Friday rendering "It's a dry heat" null and void.

New condenser is in the mail to be coated... I'll take ANY improvement!

So looking at my favorite trouble spots, automotive AC, I choose to start out with one I can monitor the head pressure and fan speed on. No, not the one giving me trouble - they ALL do. Trouble is the system literally blowing up like you see in the youtube tests as Patch blows out the high side sealing washer on the compressor hose and the Dodge pops the relief valve at 450+ Psig. The Dodge ECM doesn't kick out the AC clutch due to a bug thus it will pop the relief 2x or more per year and dump 1/2 the system charge aka 1 LB. I don't expect it to cure the bug as the second part is not enough fan.

What I would like to see is once I get the fan spinning and let it idle is lower head pressures. On fan speed 3 I will see 350-400+ Psig idling. Speed 4 is asking for it to pass 400 Psig even with ~1400 RPM on the fan at engine idle.

I have a crew cab, but, the Mega Cab's have the same size AC system and it's way undersized for it. IMO coating both the evaporator and condenser may help the undersized system out to cool down that "School Bus" Megacab.

Here is the data readout I will use. It's showing 454Psig max peak on a cold start. (The current reading Psig is the AC shut off as it was running away fast.) I have since added fan commanded % and Fan RPM. This is condenser overheating due to no fan RPM. I don't expect this to be cured.

View attachment 53087
I like the idea it makes sense...

I know many do not agree on the EnviroSafe organic Freon replacement mainly because of the fire issue However; I use it in all my vehicles aside being organic IMO the best feature is it operates a lower head pressure and you use much less than you would R134a etc. the end result is colder air.
 
@79jasper Yeah, I need to add a "T" and put a cut out switch on the Dodge.

@FellowTraveler Even with EnviroSafe Industrial the root of my problem is shedding enough heat off the condenser. Perhaps it's ability to move more heat than R134a is why the head pressures are high on the Dodge at idle.

The Dodge has a temp probe in the evaporator to kick out the compressor to prevent ice up. So EnviroSafe Industrial (1up here as it's colder than the standard Envirosafe stuff.) does a damn good job in it. Industrial's "pressure" is way below freezing for the GM accumulator low side switch - so unless the fan is on high the GM evaporator will ice up and block airflow. (Their standard stuff looks to be in line with the GM switch pressures for R134a and not iceing up the evaporator.) The amount of water coming out of the AC drains on a dry AZ day is impressive with the stuff. However it will relief valve vent just like R134a when there isn't enough condenser airflow. Added risk of hydrocarbon diesel run-away. Regardless it has high head pressure as well when idling. The 2003 Dodge is a mess for enabling high idle that would help solve the problem.

The Dual air Yukon also needs help and it has a aftermarket condenser fan strapped on it. I also raised the idle RPM in the ECM just for better AC. But, I can't monitor fan speed and head pressures with it.
 
@ WarWagon be careful having him do your condenser. Once you see the results you will be thinking like me about your power bill and the home a/c unit. How
To get it done may be a challenge- haha. Really idk if it would save $ or not. Working at a gubmint job, I will be talking to the head of the hvac dept and his guys about it soon. I know it could shed/ collect the heat faster if both coils are coated, which in theory saves blower fan times. Idk if it will really help compressor run time much at all, I think it would save some. If thermal load for a day is the same...then maybe the efficiency of run time may not save much at at all.

Any HVAC engineers on here?

About autos, I knew the efficiency from it in btu shed per area, but only understood it as how well it MAY work. There is a guy in Vegas with a mega hotrodded p400 I been a little involved in. When i spoke to him about maybe doing my cooling stack, he already had his new aluminum stack parts on order. There is a local guy that does the coatings like Chris, but way more
Expensive, and I can paint better than him, (plus we don’t get along) so... Chris will get all my business instead of a local guy. But the owner of the hotrod hummer uses him for his other cars. So he had him do the stack. We tested the other a/c, oil cooler, trans cooler all aluminum also btw- then installed coated ones. That carved my decision in stone. If you notice my posts went from maybe I will do it to I am not going to drive my hummer until I can do it. Yeah, that was the day.
 
The open design of the ram lets awesome amount of air at it, but they are impossible to protect when pworking on it. I have been waiting to see someone invent a plastic shield that just drops over the front to protect it for (actually from) mechanics.
 
FCA has gone away from the grill attached to the hood starting around 2013. They dropped the entire "big rig" look so they can look like everything else again including hood badges like the *gasp* 6.5 Turbo had and the Duramax Allison has had. Even added big letters for their "RAM" rebranding F-up. Need the big letters to tell it apart...

Easy to clean bugs off as well. @Will L. The shield is available in black powdercoat: no dice on plastic.

https://www.genosgarage.com/product/wd-cond-gr-0307/air-conditioning
 
Results are delayed as I am recovering from frostbite on my nipples due to improved AC performance. :nurse:

Before (past the critical 105 outside temp) at 106 degrees F:
AC High side pressure runs away to over 400 psig with blower on high at idle. Compressor max pressure short term peak spec is 430 psig. Long term best life under 300 psig. System vents over 450 psig.

Blower speed 3 will creep up to 400 psig from 350 psig at idle.

IMG_20180625_183555264.jpg

IMG_20180622_142830761.jpg


IMG_20180622_142838645.jpg

b.jpg

Speed 3:

IMG_20180622_142713066.jpg

IMG_20180622_142709028.jpg
 
After:
AC High side 302 psig blower on high at idle.

IMG_20180703_204146367.jpg

a.jpg

IMG_20180703_171037563_HDR.jpg

View attachment 53349

IMG_20180703_171022307.jpg

Going down the road 45- 75+ MPH high side is around 200 psig. Before it was kicking the fan on over 230 - 250 psig . YMMV as this is biased on Envirosafe Industrial refrigerant. Efficency, ability to move more heat than R134a are factors I do not explore. Case in point with humidity at 7-15% at 106+ degrees out vehicles with the Industrial refrigerant are dripping water out the evaporator drain - R134a won't do that in these conditions.
 
111 Degrees yesterday. The Dodge AC is the last vehicle standing. 356 psig on the high side idling with the fan on high.

2002 Yukon's aux pusher fan caught a rock and pounded it into the condenser resulting in an immediate system discharge. Followed by an hour drive home in 108 weather with the windows down...

Patch's P.O.S. R4 compressor started leaking at the body O-rings and trashed the system from a low charge. IMO GM should have gone bankrupt in 1995 from the extended use of the POS R4 compressors - it certainly sold more imports with systems that reliably blew cold air with TXV's over the obsolete FOT design.

:facepalm: I don't have time to send the new condensers for Patch and the Yukon in to be coated. :muted: Dammit.
 
So ambient temperature and humidity not exact, more than 10% in high side pressure with lower vent temperature output. Dude, that’s nice results!

That would extend compressor life, I wonder by how much. Probably too many variables to really determine, but eliminating more than 10% and maybe 20%, that is massive.
 
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