Targa80’s Classic Retrofit Electrocooler Installation Part Deux
 

When I installed my CR Electrocooler in the early part of the year I had a vent temp of 39F/40F which made the car feel very comfortable. I live in Florida and at that time The temps were in the mid 70’s and the AC was up to the task. Fast forward to mid August where the temps hit 90F and the humidity can be as high as 80%. Recently, I noticed a lot of condensation on the evaporator/blower and the ducts. I tried tweaking the ECU settings in order to lower the vent temps. The best I was getting was low 50’s on vent temp and high 80’s on the cabin temp. Driving in the car with a temp gauge on the dash showed a temp of 120~130F. When the car sat in a parking lot for 20 minutes that temp shot up to 150F. With the hotter vent temps it felt like the air out of the center vents was not forceful enough.

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So, I have three issues I need to resolve,
1. Condensation,
2. Vent air not forceful
3. Heat soaked from sun


Problem 1. Condensation:

Purchased the following from local HD:
R-6 insulation wrap.
Water proof silver tape.
Double reflective insulation.

Used the R-6 duct insulation to wrap the evaporator/blower and all associated ducts. It is important not to crush the fiberglass flat. If you do you lose the R rating. Took the car for a drive and when I returned the unit was in my opinion no longer sweating and the vent temps had improved a little.

http://forums.pelicanparts.com/uploa...1629409051.jpg

Once everything was installed I used the double reflective insulation to add an additional barrier between the evaporator/blower/ducts and the rest of the frunk.

http://forums.pelicanparts.com/uploa...1629410528.jpg

Everything was then covered with the frunk carpet.

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Problem 2. Vent air not forceful

I closed off the fresh air top vent completely so I would only be using recirculated air and not blending 90F fresh air into the system. Doing this reduced the amount of forced air out of the vents. I actually did a jeri-rig setup using the old fresh air blower attached to an output of the evaporator going to the center vents. The air flow did increase but it added additional ducting to the system which added to the condensation issue. The 40+ old motor started to squeal so I have put it to the side for now. Might go back to it at a later date. I noticed that the CR evaporator has a shut off valve on one output on each side. This valve is operated by the fresh air slider along with the fan speed. It does not control the actual fresh air entering the CR evaporator/blower. I decided to cap both of these outputs and use one end for the CR evaporator sensor location. This improved the air flow to the center vent.

I had a conversation with Tonger and he told me about his idea of just doing away with the two blend valves Completely. I know that I have not used my heat or defrost in years. So, I removed both blend valves and only have the recirculating lines going to the blend valve holes. I still kept the lines going to both side vents and the line going to the bow tie and passenger side foot well.

If I need to I can hookup the two heat lines on each footwell to the window defrost.

Problem 3. Heat soak from Sun:

I have scheduled an appointment on Sept 3, to have all the windows covered with ceramic tinting that meets Florida laws. From talking with other Floridians the tinting will drastically reduce the heat that builds up in the car from the sun. This will relieve some of the load on the AC system due to reduced temps in the car and hopefully help bring the vent temp down along with the cabin temp.

Other areas to consider if you have not already:
- dynamat or similar insulation between carpet and floors. A ton of heat comes up through the floor
- same under and behind rear seats
- seal and insulation behind door panels and rear side interior panels
- renew window seals and window felts as needed
- renew door seals as needed

Not sure if anything can be done with the targa top to improve thermal efficiency but I would imagine it lets a lot of heat in and doesn’t do much to keep the cool in either.

check the refrigerant charge,the best time to charge it at maximum load.
do these have expansion valves? is it adjustable, is the sensor in the proper place?

if you need more air flow the flexible duct is restricting it somewhat due to turbulence. if you can install some thing that is smoother on the inside it will help.

Thank you for your suggestions and I do appreciate them. I did consider those issues when I did an off chassis restoration in 2001. I added dynamat/equivalent to the entire inside of the chassis to alleviate noise and heat transfer from engine bay. Replaced all window/door/targa top seals. Also, Rebuilt the targa top. Today, after being parked for 20 minutes the car was heat soaked and the dash temp gauge read 150F. I had purposely touched the inside liner of the targa top and it was cool to the touch. In the engine compartment I had replaced the insulation shield that covers the wall of the back seat rest and the targa rear window shelf. My main internal heat issue is from the glass not being tinted for UV and thermal heat transfer.

There is the heavier heat ducting that is used in the engine compartment and I believe it is smooth walled on the inside.

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Pat, with the products you used to insulate the car body, are you concerned about trapping moisture? BTW, your work deserves the highest praise.

The reason for the condensation is due to the low temp ~50F of the outside case of the evaporator hitting +90F frunk air. Having a barrier of fiberglass separates the two temps and prevents the majority of condensation from developing. In my opinion the evaporator/blower internal insulation should have prevented condensation on the outside shell. The two drain holes allow any internal condensation to drain out of the evaporator/blower housing.

I’m asking about the dynamat etc. I saw a thread somewhere here where a P was finding trapped moisture. This something I’d like to do but still thinking on the consequences. Thanks.

PS: I had to move the 911 to get three cars in, because of Hurricane Henri. In less then the minute or two it took, the tach cable failed. LOL

Bill,

Sorry, my mistake. Before I repainted my car I coated the car chassis with Por15. Once the chassis was painted I added the dynamat to the inside of the cockpit. I have not had my car on the road during rain in a long time. The car is garage kept and driven at least once a week. No moisture issues noted in the past 20 years.

Decided to run the car in the garage with a high idle for 10 minutes with the garage door open and this is what I came up with:

90F on dash thermometer:

http://forums.pelicanparts.com/uploa...1629584148.jpg

Kept idle high at 1900 RPM’s

http://forums.pelicanparts.com/uploa...1629584293.jpg

Voltage = 13V, Amperage = ~ 3amps

http://forums.pelicanparts.com/uploa...1629587157.jpg

Digital cabin temp = 82.9F, Digital vent temp = 42.8F

http://forums.pelicanparts.com/uploa...1629587328.jpg

The CTS was set to 21C and the laptop displayed the following:

http://forums.pelicanparts.com/uploa...1629587596.jpg


In the garage the car was very comfortable when the vent temp was in the low 40’s and cabin temp was in low 80’s. I am hoping that the window tinting will prevent the heat soaking in direct sunlight. The tinting of car windows is very popular in Florida and not just for aesthetics, the main reason is the heat soaking and removing the stress on the AC system.

I see where you used a laptop to fine tune and view the settings of the ECU. Does the standard smugglers box install allow for easy future laptop connecting?

It does. You can also route the cable from the cabin so you can sit in comfort while checking/changing configs.

I had a small hole on the left side of glove box used it to route cable to the underside of dash then through the existing grommet into smugglers box. When not in use it is in the glove box. CR recommended not to leave the cable connected to ECU since it has a small interface circuit board on the usb side of cable. I have had no issues that I know of leaving it connected to ECU while stored in glove box. This is also convent for monitoring EXU while driving for test purposes. I would like to see a Bluetooth connection instead of a usb if possible.

At risk of cluttering with accolades:
Great, thanks, and stay cool!

Today, I went and had the window tinting done on the car for an out of pocket cost of $403. It took three hours for the tech to complete the installation of the ceramic tint on all the windows. The big issue was the targa window, the tech tried to do it with one sheet. Due to the two bends in the window the tech had to do three strips from drivers side to passenger side with a slight overlap that followed the lines of the defroster elements. The outside temp was 90F and sunny today, the dash temp while driving was at 110F down from 120F. Parked the car in direct sunlight for 20 minutes and went shopping. Came back and dash temp was 120F down from 150F before tinting. Won’t know the actual overall effect of the tinting for a couple of days. But being able to reduce the parking lot dash heat soak from 150F to 120F is an improvement.

Car before tint:

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http://forums.pelicanparts.com/uploa...1630699283.jpg

After tinting:

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Tint looks good! I expected the targa window might be a bit of a challenge. Sounds like the tint will improve things. Enjoy reading about it.

Looks great! What did you use for the windshield?

The following window tints are legal for use in Florida.

Front windshield used Llumar ceramic Air 80 clear window tint.

Door windows used Llumar IRX 30CH window tint.

Rear window used Llumar IRX 50CH window tint.

I have added both the defrost vents to the two outputs with the valves to close the defrost using the center slider. I decided to do this so it will assist in moving the hot air away from the windshield and hopefully add to the circulation of air in the cabin since hot air rises and can be pushed to the back of the cab to create a circular motion of air.

Took the car out for 1/2 hour ride. Dash board temp was 80F when I left the garage.
Outside temp was 90F and 70% humidity with some scattered clouds so it wasn’t direct sun all the time.

The dash temp rose to 90F after leaving the garage and pretty much stayed there while driving until I stoped and shut the car off for 15 minutes. The dash temp rose to 105F and came back down to 90F once I started driving again. This test was with the two defrost vents open and pushing cold air past the windshield.

The center vent temp dropped to 48F and the cabin temp dropped to 84F. Granted it was not as low as I would like but it was comfortable compared to the heat outside. I would like to reach the low 40F on the center vent and 80F for the cabin temp.

I will say that if you are installing the CR system and you live in a hot/humid climate like Florida I would highly recommend adding the ceramic tint to all the windows. The tinting can eliminate a lot of the solar heat transfer into the cockpit. Expect to pay around $400 to have a Targa professionally done.

Earlier in this post I had mentioned that air flow from the center vent was minimal. In other words you can’t feel it hitting your face when the vent is pointed right at you. I did experiment with using the old fresh air blower as a booster for just the main middle vents. Unfortunately the old motor had a terrible squealing noise after running for a while so I shelved the idea until just recently. A friend provided me with his used fresh air blower motor and I was able to install and run the booster with no squealing noise.

The first thing I had to do was to devise a way to use the old fresh air motor with out the large air box. Home Depot sells a pvc circular drain fitting that was just the right size. Added two L brackets to hold it to the blower housing and used thin sticky window foam insulation to create a seal between the two parts. The addition of a 2’ 90 degree elbow and a 2” end cap completes the assembly.


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As you can see below I Spliced a 4 wire cable into the main blower power cable to provide the slider switch three speed control to the booster. Used the top passenger connection from evaporator/blower to booster and then from booster to the center vents.

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Covered the area with a thermal blanket.

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With the carpet in place the booster motor doesn’t take up that much additional space in the frunk

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The outside temp today was 90 degrees and sunny with 70% humidity. The garage temp was 86 degrees. Fired up the car and took it for a half hour drive. The evaporator and cabin temps dropped very quickly and hovered at 79 for the cabin temp and 46 for the evaporator temp. With the added booster I could now feel air on my face when I adjusted the center vent. The booster did add a slight increase in fan air flow noise but with the engine running and the radio on it did not bother me. In a few days I will finish the mod off by adding insulation to the booster and added duct work.

http://forums.pelicanparts.com/uploa...1657823778.jpg

Thank you for the well documented install Pat. I'll be doing my own install sometime in the future, and your work will be a huge help!
As a side note, would the rear heater blower from a G model be more compact and easier to implement as a booster? Also worth consideration are the inline heat blowers from a Carrera.

I have my heater fan motor from the engine bay and decided not to use it because it is single speed and is a smaller squirrel cage fan.

The Carrera in line fans are $$$$ and single speed so in my opinion are a non starter.

There is an in-line booster fan on the open market that is cheaper than the Carrera option. Again it is single speed and I have been told is is loud when running.

The mod of the original fresh air three speed fan is fairly cheap to do so if I decide to not use it. No big deal.

Hey Pat, any chance you can do a test with the same conditions without the additional blower installed? You might have already cataloged this in a previous post

I have been using the system for the past year and depending on outside temps I have had evaporator temps as low as 39~40 degrees and cabin temps as low as mid 70’s. With the outside temp today at 90 with 70% humidity the evaporator was running at 46 to 48 degrees with cabin temps at 79~82 degrees. Once the cabin is in the high 70’s to low 80’s it is very comfortable. Granted you will not freeze and you will not be sweating either. The issue is the volume of air being moved so it takes longer to lower cabin temp without the booster fan.

I think people need to understand that this system is not like factory air that has a high CFM fan that will make your hair move if you aim the vent at your face. Our cars are limited by frunk space available for the evaporator/blower. Could an upgrade evaporator/blower be designed for more CFM throughput by making the unit larger so it protrudes further into the frunk. Maybe, but that is an issue for CR to resolve. The work I have done is to make the stock system I purchased function better than just out of the box based on my own installation specific to my car.

^ We hear you and have been busy!

Currently in test we have a Gen2 blower design based on a bigger fan and a less restrictive evaporator. It does shift more air but the air is a few degrees less cold when the flow is fast.

I have this in my own car right now and we have hot weather on the way. I plan to put out a video as I have trip planned on the hottest day next week - predictions are 37C / 97F and sticky.

TBH, I am on the fence with the flow vs cold thing - very subjective. What I will say is that you can have the option to turn the new fan down and I am mostly using the lower speeds after a minute or so.

We appreciate the established customer base so we are planning on offering an upgrade kit for those with Gen1 blowers. This would be a kit of parts to allow upgrading the blower to the larger fan and less restrictive evaporator.

The blower is overall about 10mm wider but the main body is the same profile. The fan and the 'spine' of the blower are new. We have moved the expansion valve to the vehicle right side which makes the install easier for LHD vehicles (the majority of our customers).

We hope to have this ready towards the end of the year.

Johnny,

Thanks for the update info.

RE: Problem 2. Vent air not forceful.

I agree with Targa80, it is very evident in my 86 Coupe that with no restriction on the fresh air intake vent the supply air volume and velocity from the side and center vents is respectable. However, as noted, when the intake is blocked off, which is necessary in my climate, there is significant reduction.

I believe the current return air openings at the footwell blend valve are not adequate and are choking the system. It does seem possible that bypassing the interior heat duct fans and permitting the return air directly from the cabin to enter via those duct connections would increase volume of air and reduce the choking effect enough to improve supply air performance. I know Targa80 did that, but I likely will try that on my car (1986), in a couple of weeks.

If the CR AC V2 fan is capable of overcoming the possible choking/static pressure from the current blend valve return openings perhaps that might improve overall supply air performance without bypassing the footwell heater fans.

Nice work Pat! Def plan on looking into clear uv tint to help with the solar transfer into the cabin. I insulated the fan box and assume I'll proceed to insulating the remainder like you to help get those vent temps down as low as possible. Luckily we don't have the humidity here in CO to fight on top of the heat like FL. Keep up the good work! I'll be paying attention to anything I can do to get cooler temps on mine! Cheers,

Pat.

Is this clever, cool booster still installed? If so, does the duct work and the thermal blanket serve to mount it in place, or did you add another mount?

Mike

I did have an issue with the old motor squealing after it heated up. Was given a spare from a friend who purchased a new one for his car. It lasted about a week before it gave up the ghost. Finally, opened the wallet and purchased a new motor. Installed it in the casing and has been working as a three speed booster motor with no issues. No need for additional clamping the two ducts hold it in place. The thermal blanket and the carpet also help to hold it in place. It would be just like storing something in the trunk. It is not an issue as an object moving around in the trunk

Hi,

Hate to be a bother, I've looked far a wide at my Home Depot, apparently not all carry the same stock. I also searched on-line for the part (your PVC circular drain fitting) but after 40 pages or so, no luck. I have found some pieces which might work but are larger than the one you have (well larger in some places and smaller in others). Anyway, is it possible to get a photo of the bar code number so I can search for it on-line?
After searching the Jenson Beach home depot, I might have found the part

Model #435962

https://www.homedepot.com/p/OATEY-Round-White-PVC-Area-Floor-Drain-with-Screw-In-Drain-Cover-435962/305248410

Mike,
That looks like what I bought at Home Depot.

http://forums.pelicanparts.com/uploa...1666137160.jpg

You will need to cut a notch for the power cable to the motor.

http://forums.pelicanparts.com/uploa...1666137267.jpg

I used two L brackets to hold the drain to the motor casing. Also I added a strip of window weather stripping between the motor case and the drain to prevent air leaks.

http://forums.pelicanparts.com/uploa...1666137398.jpg

I used a 2” end cap to close off the second output port and you can use a 2” street 90 degree elbow on the input of the drain side.

http://forums.pelicanparts.com/uploa...1666137504.jpg

I know it is not pretty, but it works and it is not a burden on the wallet.

Thought I’d share my progress based on your clever idea. Here is a picture of my fan and the electrical hookup. I managed to use an old plug from my wiring harness, had to add one wire to get all three speeds. All three speeds are working. The number system for I, II, III speeds and the numbers 1,2,3,4 on the plug are kinda fun to decipher, not quite as straightforward as I’d have done it. Oh well, only ducting, thermal blankets and system securing. Definitely blows some air at position III!

http://forums.pelicanparts.com/uploa...1667409305.jpg

You should be able to take the upper duct hose in your pic and connect to booster fan output and add a duct from evaporator output to booster fan input . I recommend you do this and test to see if you are ok with the vent output before adding all the insulation to the booster motor.

Yup, got it done as you described. It is amazing the difference in the air volume on the center vent compared to the others. I can sit back in my seat and feel the breeze in my face, big improvement! For about 100$ so far its a great addition. Good thing the center vent has two separate vents, keeps the passenger happy too.

Found a piece of foam, going to use it to seat my "Frunk Drain Fan Booster" or FDFB. Hope to keep it fixed in place during braking and hard cornering. Until I find a better anchor solution. I realize the hoses are pretty good and then the foam attached to the bottom and then glued to the side carpet my be all I need. Will see.

Thanks again for the idea, help and inspiration.

Cheers, Pat