Experience with RetroAir Kit (condensation)

Anyone have an RetroAir kit installed?

I had the kit installed and I’m getting condensation issues. We looked at the unit and added an additional drain line, but I’m still getting some spitting and dripping.

System seems to cool well, but overall, not sure I find the system worth it (yet). Any pointers?

69 Coupe

I am NOT an A.C. guy, but… To my way of thinking, water/condensation comes from lack of sufficient air flow over the coils. I believe there is a copper temp sensor that is placed within the coils and regulates the compressor’s function in some way?. Bottom line is that if the compressor runs full speed and there is not enough fan/air flow, you get condensation. That’s my VERY NON PROFESSIONAL opinion. good luck

Murrieta, Ca.

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I had the kit professionally installed, but this was their first kit. They did talk to RetroAir a few times during install and I will take it that it’s installed properly.

I was hoping someone who has the kit would share any experience with similar issue.



Condensation within the evaporator (underdash) unit it totally normal, which is why adequate drains are needed.

I installed a Retro-Air unit in my S2 FHC (surely identical to yours, or nearly so). The car had originally had factory A/C. I noticed immediately that each side of the evaporator unit would need a separate drain, so I built two drains into my installation. I’ve had no problems with drainage, and am VERY happy with the whole thing (okay, it’s a bit noisy).

Bob Frisby
Boise, Idaho


Bob, thanks for the feedback. Great to know that what I’m seeing is normal and we are on track for a solution.

Can you share where you put your drain lines and how you outlet them?

Since I had my shop do this, I’m not 100% sure what they did. My car was factory AC as well, and if I understood things there were two drains already in the evaporator, and we added a third and used a Y connector to to the actual outlet.

They said the additional drain may not get 100% as the interior of the unit had an odd sloping, but feel the extra drain will help.

I’ve only driven the car a little since then, but I was still getting drips and spittle from the vents.

No condensation issues with the installation in my S1. I combined both drains on the unit to dump on the right side of transmission cover to avoid condensate dripping onto the exhaust pipes. That aside, I’d look at the installed angle of the evaporator. Could be too shallow.

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I guess it should be assumed that the drains have been cleared for any clogging up ?

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My two drains are at the lowest points of the evaporator, one on each side of the tranny hump. I don’t see how they could be combined into one. The important thing is to drain the lowest points.

The left-side drain ended up right between the two exhaust pipes, so I have a small brass tube (not rubber or plastic) extending down through the floor and between the pipes.

Bob Frisby
Boise, Idaho

Somewhere in a long ago string I posted a photo of the routing to combine both drains on the right side.If the computer guy can find a way recover a decade of photos from crashed hard drive in the ‘ol laptop I’ll post it again. But the right side basically drops straight down to right angle fitting through the side of the trans cover. Sandwiched in between is a low mounted “T”. The left side drain in the evaporator plugs into that T(via) a hose that angles down and across the trans cover. In any case I’d look at the angle of the evaporator as a possible source of moisture pooling around/under the air vents.

Thanks all! If anyone has pics of their drains that would be awesome.

Here is the install, I will see if we can angle forward towards front end a few degrees.

Pics of added drain.


I might be imagining this but it looks like there is a very slight bow in your evaporator case such that it sits high above the radio console. I mention this because my Retro installation looks the same and I also have occasional “spitting” of condensation. I keep the fan a little higher and the temp control a little warmer to keep the spitting down until next winter when I will take it down to fix. Any progress you make in resolving this issue will be of great interest to me.


I think the unit is horizontally level (and true— at the top). We did not use the trim pieces that came from RetroAir as that would not have allowed the radio console to fit, so we fabricated a few strips. The angle is the same but the unit sits a touch higher.

If I am missing what you mean, please let me know, I am totally open to any thoughts.

Sounds good. Looking forward to your solution then.

David the 2 strips you fabricated are those below the glovebox and above the A/C controls. If so what did you fabricate those filler strips from. The install looks great. My wife is begging me to install A/C into our 69 S2 which originally came with A/C as well.


The pieces circled in red were made by my Stereo Fab guy. I believe they are just a a few strips of PVC Plastic with a black crinkle paint finish.

The RetroAir Kit comes with nicer strips but they are much thicker and would not let the stereo console be used with a 1DIN Unit.

Until I get the condensation squared away, I’m hesitant to recommend the solution. However, it does appear to work but not yet to my expectations given total cost of unit and install. Maybe we are running into some beginners issues as this is the first one my shop has done. I’m still confident I can get this to work to my satisfaction, we are just not there yet.


Thanks David that is what I thought and it looks good. I installed a Retroair kit in my MGB GT and it works great and I never have any spitting issues. However the set up is completely different with the evaporator under the dash on the passenger side and with a good slope backwards and all the vents are through ducts. I’ll be interested to see how yours finsishes up before I put one in my E.

I have the same retro radio as you do and I can see that it’s a tight fit . Is the radio console the one for that comes with the E types with A/C as standard, because mine has been changed to a non A/C radio console?

Thanks Andy

I believe my center console is the original radio console. The PO had it opened for a circa 1999 1DIN unit. I put the RetroSound in.

My car came with the factory AC in place. It was completely disconnected (no belt or hoses at compressor). Since I really wanted cold AC, I decided to do the swap.

1 thing I found today was the metal valves were not wrapped and that is causing some dripping. RetroAir said a roll of cork tape came with the kit. If so, it was used or I can’t find it.

Can someone add an amazon link for the correct cork tape and I will wrap the metal per their directions.

I’ve used this stuff in that application and it works great.

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