DIY: A/C Insulation

[mikenacarato]

first off, i wanna say i love this idea!!!

second, how long until the evap core freezes over? i would put some a/c gauges on it every now and then to see what your low side pressure reading is, if you notice it dropping then your evap core is freezing up and will cause the system to shut off.

[texkid]

Originally Posted by mikenacarato

first off, i wanna say i love this idea!!!

second, how long until the evap core freezes over? i would put some a/c gauges on it every now and then to see what your low side pressure reading is, if you notice it dropping then your evap core is freezing up and will cause the system to shut off.

I thought there were safety features that would prevent that? I guess someone should keep an eye on it and let us if we screwed something or maybe tweak it a bit more.

Originally Posted by CTScott

Instead of aluminum tape, use heat/flame resistant wire loom:

It even comes in blue, red and black.

http://www.summitracing.com/search/?...o%20flex&dds=1

That is an awesome idea. I imagine one must cut a slit in order to wrap around the lines?

Originally Posted by Lazerdot

Did all but the area by the pullies. I put aluminum rap around the insulating foam and lightly tie wrapped the total. In my head ity seems cooler. Wish I had done a before after. But, can it hurt?

It should work. You be the judge. Does it feel cooler? I am noticing that I can now drive with the setting at (2) instead of the usual (3) or (4).

Originally Posted by andaconda

Temp increased to 42 degrees when I turned the fan on 4.
I wish I would have taken it's temp before the mod.

I have been noticing that as well. I am assuming that it is only blowing the air faster without adjusting temperature to the A/C; essentially more quantity and less quality?

Nonetheless, it is not too bad since supposedly you get COLDER air when set to "recirculating".

[Revsson]

Originally Posted by texkid

That is an awesome idea. I imagine one must cut a slit in order to wrap around the lines?

That's what it tells you to do on the advertisement page.

Much nicer looking than the silver wrap, IMO.

[Henry G.]

Did mine today. I zip tied the foam as I went from one end to the other, then twisted/adjusted the foam, re-tightened the zipties as necessary and cut the ends off. I found the aluminum tape at Home Cheapo, a small roll (50 yards!) was 7 bucks and change, I saw the larger roll it was almost $15, the small roll is enough to do 20 cars at least.
I rotated the zip tie buckles to the rear before taping. As Anaconda mentioned the hot tip is to cut short pieces of tape, approx 6 inches long and wrap one section at a time, I used about a 1/4" overlap, and double wrapped the area closest to the header. IMO the header is likely responsible for most the heat warming the line, so I just did the back section across the firewall, the rest is too curvy and complicated for a clean wrap.
Half way there:



Finished:



I will check the result and see if I can feel the difference later today.
Good thread and DIY thanks guys.

[Dage]

It is not a good idea. theres a reason why toyota does not did that.

I work in refrigeration and climatisation.

The temperature of the air supply must never be lower than 50 degre F.

You need 20 degre F between the inlet and supply.

Your compressor will compress liquid refrigerant and its not good for longue time life.

without insulation, you gonna have better heat transfer for refrigerant vapor compress.

So, i don't think that is a good idea.

[n00b]

Originally Posted by PK198105

ok...guess you didn't read properly what we did.we're not insulating the refrigerant as it enters the compressor but after its refrigerated so that it doesn't warm up when it goes back to the cabin.

both of you are incorrect.

The low pressure line is for refrigerant going to the compressor. It's a good idea to insulate the low pressure line to keep the refrigerant cool as it enters the compressor. The cool refrigerant helps cool down the compressor. The high pressure line goes into the cabin. The high pressure goes through the expansion valve making it a low pressure liquid and cold. The warm air passes through the evaporator and boils the refrigerant into a cold gas.

Why is it a good idea to insulate the high pressure line? Because you don't want your engine heat to warm up the cooled refrigerant that will be entering your cabin. From the pictures posted, it looks like the high pressure line is VERY close to the exaust manifold. Basically, your condenser is cooling the refrigerant, and a few feet later, your exaust is warming it back up again!

Seriously... just do a damn google search on how a/c works. The high pressure line is the one going to the evaporator, the low pressure line is the one going to the compresser.

[EasyDriver]

I used pipe insulation only on mine and also did the lower area by the compressor. For the area by the engine mount and alternator pulley I took a 3" x 4" piece of aluminum dryer vent, bent it half mooned shape, over the low pressure line and over the low pressure line. I kind of wedged it in place firmly.

I get cold air in under 3 minutes...my vent thermometer (thanks for the tip on finding that texkid!). I'm reading 38 degrees vent temperature. I did not have the thermometer before the project, but I know it was not nearly as cold.

What kind of vent temperature are those of you that have used the aluminum tape getting?

[EasyDriver]

Correction: I took a 3" x 4" piece of aluminum dryer vent, bent it half mooned shape, over the low pressure line and over the high pressure line. I kind of wedged it in place firmly.