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Insulate low side hose?

Posted: Mon Jul 08, 2024 3:14 pm
by RossL
I just installed the Vintage Air kit on my 55 Thunderbird. The tech from Vintage Air suggested that I insulate the low side hose (from evaporator to compressor) because there is a lot of heat in the engine compartment. What is the best product to use for this?

Should I consider insulating any other lines/hoses?

My gauge reading are Low 25, High side 235. Outside temperature 90 humidity 75%. Thermostat in vent reads 42 degrees.

Re: Insulate low side hose?

Posted: Tue Jul 09, 2024 8:14 am
by tbirdtbird
It is nearly standard practice to insulate as you describe.
The big box stores carry plumbing pipe insulation which works, but because you have already installed the hose, you would have to slit it lengthwise to install, then wrap with duct taper or similar of your choice. This type of insulation tends to not be black, which I prefer, and is not very flexible.

A better option for others contemplating this issue is to go to an actual wholesale plumbing shop and get the black very flexible and soft squishy pipe insulation, and slip it over the hose before you install, being careful to not get crud into the AC hose.

Yeah, they never tell you everything you need to know upfront.

The numbers you give are excellent, good job.
I am not aware of the need to insulate other lines. The hi side lines run hot, so you do not want to keep that heat in.
Be sure the TXV is held tightly to the evap exit, and then wrapped tightly with an insulating tape such as prestape

Re: Insulate low side hose?

Posted: Tue Jul 09, 2024 12:43 pm
by Carguychris85
I insulate my low sides hoses with a black foam pipe insulation from Home Depot or Lowes. It is already pre-split and had adhesive, but I still wrap it with black duct tape. On the GM stuff I work on, many did not come with an accumulator blanket. GM has discontinued most that they ever offered, except the one for a late model Express/Savanna van. The good news there, the blanket fits most GM accumulators back to the 70s. Won't apply to your Thunderbird but it might on other vehicles in your garage. I insulated the low side lines, added the accumulator insulator blanket and installed a manual heater shut-off ball valve on the 1987 G20 I recently built the a/c system on. Center vent dropped about 5-7F between insulating and the heater core shut-off valve.

Re: Insulate low side hose?

Posted: Tue Jul 09, 2024 12:50 pm
by Tim
Pool Noodles. LOL

Don't wrap metal accumulators. They will rust over time.

Re: Insulate low side hose?

Posted: Tue Jul 09, 2024 3:34 pm
by tbirdtbird
I have done heater core shutoff on a couple of cars. The dash controls do not always get the job done, and gotten 5 more degrees, also

Re: Insulate low side hose?

Posted: Wed Jul 10, 2024 8:22 am
by JohnHere
Grainger's has what they call "Oil-Resistant Buna-N Foam Rubber Pipe Insulation" that can be used for just such a purpose. Buna-N is flexible, and the sections are available in various lengths and ID's. They have to be slit, as already mentioned. The slit and the ends can be sealed using the pictured tape, available in the Orange Home Center.

Re: Insulate low side hose?

Posted: Wed Jul 10, 2024 8:23 am
by JohnHere
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Re: Insulate low side hose?

Posted: Wed Jul 10, 2024 10:05 am
by Carguychris85
Tim wrote: Tue Jul 09, 2024 12:50 pm Pool Noodles. LOL

Don't wrap metal accumulators. They will rust over time.
GM started factory insulating all their aluminum accumulators about the time they started using R134a. I have never seen an insulated aluminum accumulator rot out atleast here in Texas. We run ac probably 9 months out of the year as well not including defog function.

Re: Insulate low side hose?

Posted: Wed Jul 10, 2024 10:07 am
by Tim
Carguychris85 wrote: Wed Jul 10, 2024 10:05 am
Tim wrote: Tue Jul 09, 2024 12:50 pm Pool Noodles. LOL

Don't wrap metal accumulators. They will rust over time.
GM started factory insulating all their aluminum accumulators about the time they started using R134a. I have never seen an insulated aluminum accumulator rot out atleast here in Texas. We run ac probably 9 months out of the year as well not including defog function.
Steel does not aluminum.

Re: Insulate low side hose?

Posted: Wed Jul 10, 2024 10:24 am
by Carguychris85
Tim wrote: Wed Jul 10, 2024 10:07 am
Carguychris85 wrote: Wed Jul 10, 2024 10:05 am
Tim wrote: Tue Jul 09, 2024 12:50 pm Pool Noodles. LOL

Don't wrap metal accumulators. They will rust over time.
GM started factory insulating all their aluminum accumulators about the time they started using R134a. I have never seen an insulated aluminum accumulator rot out atleast here in Texas. We run ac probably 9 months out of the year as well not including defog function.
Steel does not aluminum.
That makes sense. Thank You for clarifying. Who has a steel accumulator? Ford? Dodge? I think the one on my 2006 Ram with a Hemi may have been steel. But I only kept that lemon of a vehicle about 5 years. The OEM battery in it outlasted 3 of the 545RFE transmissions. At ~90K miles on its 4th transmission since new and out of powertrain warranty at that time, I traded it off for a 2012 Titan. That Ram had one of the worst ACs ever put into a vehicle as well. Condenser was far too small and relied on a weak little electric fan as it was sitting next to the radiator and clutch fan. The system would cut off on the high pressure switch in 90F westher with the OE specified charge volume. The 3rd gen gas Rams all had a horrible AC system design. I went from one of the worst vehicle ac systems to one of the best in the trade as well.