So I just realized there are 2 different version AC units. BUT i cant figure out which one comes in which model/car/year or if that is even relevant..

here are the different units...

Unit #1
Note- the top "rectangle"


Unit#2
Note- this top rectangle has multiple steps..



What is the difference between these units? which came in what model etc?
I've looked in 6 different cars, 5 are 93s.
the only thing I could make sense of is the ones that had unit #1 did not have sunroofs, and the ones with unit #2 had sunroofs...

But, that doesnt make sense to me why a sunroof would determine a different A/c unit.....

 

It appears that only touring models had the a/c installed in Japan, and the base and
R1 or R2 were installed stateside. The factory installed system is slightly different than the "stateside" installed.

 

Not true, R models came with AC from Japan, infact, they all did .

I'm guessing here, but the AC change in 94 "may" have changed the condenser core, resulting in that shape change?

 

There 2 different a/c systems.

1. Factory installed Nippon Denso units.

2. Port installed a/c that use the Mana System.

None of the parts are interchangeable as thread size and pitch are different on compressor, dryer, evaporator and condenser.

You can get most replacements parts for the Denso system but not for the Mana one.

 

There are two sure fire ways to tell if you have a mana or denso system. Neither of which can be done by looking at the outside of the evap's box unfortunately.

1. Measure the inlet and outlet ports of the evaporator:
M14x1.5 | 9/16x18 inlet and 7/8-14 outlet = Denso
M16x1.5 inlet and M22x1.5 outlet = Mana

2. Remove the evaporator from the enclosure box and take a look at the expansion valves:

Denso looks like this:


Mana looks like this:


Msg me if you need any more information. I've got a very informative thread with lots of pics going on another forum but I don't want to post the link here because I'm not sure if that would be breaking any rules.

Lane

Oh and redlightrich & FC3S1991 are correct when dealing with LHD spec FDs imported to the USA. Mana systems were installed on US soil to reduce levies / taxes when importing some FDs to the USA. I believe we're the only country that had to deal with that though...

 

interesting... well for my purposes, the drain hose is slightly offset depending each version... how do you determine if it was installed stateside or factory?

 

The tourings got the Nippon systems R and base cars got the MANA. There's where your sunroof/no sunroof differences came from. The compressor itself is the same between both systems, just everything else is different. There are also slight differences in the evap core units between 93 and 94+ cars to deal with the airbags but it is possible to put a 93 evap core into a 94+ car with some modifications.

 

My 94 touring has a mana system

 

Interesting, my car had a MANA evap core in it (also a 94 touring) but I figured it had just been swapped out at some point as none of the rest of the system was there and the A/C had been ripped out of the car at some point.

 

Yeah no way on telling what model came with the denso system, I hate it because not being able to get a replacement dryer for it

 

The only consistent ways I've seen for verifying what evaporator is installed is by getting dirty and using one of the two techniques I posted above. To my knowledge, there is no sure fire way to tell which is which by identifying external features on the evaporator box. It would be nice if it turns out there's an easier way though, so I'll have to follow this thread closely

Lane

 

In an effort to clear things up, I want to show the build sticker on the right side door pillar. It clearly shows A/C
N

My R2 is exactly this way too. When I order belts using vin, they come wrong. Leads me to believe what I thought.

Both these cars do have A/C in them though.

 

The drier is also different on the two systems and much easier to check than taking the cooling unit apart to view the expansion valve. There is a sight glass on the piping going into the drier for the denso unit. If there's no sight glass, then you are looking at a mana unit.

If anyone is interested, I have a complete MANA system for sale...

 

Incorrect. Compressors are the same for Denso vs MANA. Although the compressors are different depending on refrigerant.

Yep. The Denso parts were used on a bajillion Toyotas, Porsches, etc. The MANA parts? They all appear to be unique to the RX-7. How this was deemed cost effective, I'd love to know.

 

1993 Touring cars were primarily the only cars equipped with the Denso system. I have yet to see a 1994 with a Denso system, and every time I see pics of a car for sale I always look.

Denso driers are errywhere. Try ACDELCO Part # 1510785.

Now...if you meant to say MANA driers can't be had, then yeah, that's a true statement.

 

FML. So much bad info.

If there's no sight glass then you're looking at a MANA 1995 car with R-134a from the factory.

If the sight glass is on an aluminum block that bolts directly to the drier you have a Denso system.

If the sight glass is in the line leading from the drier, but not ON the drier, then you have a MANA system.

I have no idea how they configured the sight glass for an R-134a Denso system, or if they ever even made such a critter for North America....1995s are rare enough as it is.

 

How about pulling the glove box and looking for a sticker?

I dunno who ZTX is/was but I sure would like to find out. Their stickers are on the condensers too.

 

Interesting. I wonder how consistent that method is though. I know my 93 Denso evaporator box doesn't have a sticker on it. Maybe it fell off, or maybe only the MANA evap boxes have stickers?

Lane

 

All three of the MANA boxes I've dealt with have one. I seem to recall the little ND stamp somewhere on the Denso box that I dealt with, but that's more of a fuzzy memory than a hard fact.

The other fuzzy memory that's in my head is that the MANA thermoswitch has 2 wires leading to it and the Denso switch has 4.

 

I looked under the glove and saw the MANA sticker. No removal of ANYTHING

Just for reference: '95 PEP
My dryer did not have a sight-glass and it was black.
My stock refrigerant was for R134a

 

I have a 94 touring and was told they came with Japan Denso system. Somebody snaked my line and I've been trying to get it back together. I bought two lines and now two dryers that are wrong after reading this post I can now see I have a Mana system or dryer setup.

It looks like I need a working Mana dryer and a condenser line anybody?

Before Picture of my car with AC

After Picture trying to piece it back together. I bought this dryer from Ray who has them specially made for I believe a denso system but I can now see it's wrong for my car.


Denso dryer system

Mana dryer system

 

Just grabbed these pics from my '93 FSM, hope it helps clear up some confusion





No idea why they're sideways, showed up normal when I saved them. Have high rez if needed

 

Any MANA drier you buy at this point will be sketchy since the desiccant is likely already saturated.

I'm in the same I-need-a-drier quandry, and I'm working on a solution. I have almost all the parts needed, but I'm still waiting on one to come in. Once I have everything together, I'm going to tear my system apart and confirm that it will all work. It will solve your need for a line as well as your need for a drier.

The driers Ray was having made were for the MANA system. I spoke to him last week and he can't get them from Mazda and he can't get any more made. The Nippondenso system driers can be bought at any auto parts store since they were used on 3 billion different models.

 

wow. thanks to fc3spowa, thats the closest thing to a solid answer i could find about which system i have.

 

Does anyone know if you can use Denso lines with a MANA evaporator?

I pulled out my AC system back in 2008 when I installed my VMIC and I've been trying to install it again off and on for the last 3 years. I've finally gotten to where I'm making some headway but I'm running into issues getting lines to work.

My car came with a MANA system but you can only get Denso dryers now. If the high pressure lines from the Denso system work with the MANA evaporator (I'm really just concerned about the high pressure fitting on the evaporator), I can finish this install.

And if it works I'll be looking for a couple Denso lines. If not, I'll be looking for a whole Denso system.