Air conditioning a D in the tropics

C

Citquery

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Fellow Frogger
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Adelaide
I am initiating this thread on behalf of the new owner of a 1974 DS23 Pallas BW35 automatic (carby) sedan which was delivered to its original owner in Adelaide in September 1975 and spent the ensuing 45+ years in South Australia. I owned the car for 26 years prior to its recent sale to Michael, a resident of Singapore.

When I purchased the car, it was fitted with what I understand was a typical air conditioning system of the era: block-mounted York compressor; twin, fan-cooled condensers, mounted in the front wheel valances behind the ventilated front bumper bar and evaporator and controls mounted in a locally-fabricated shroud located under the standard ventilation controls.

I removed the air conditioner soon after purchasing the car, mainly because I only drove the car in mild weather and I didn't like the concept of driving the compressor via the camshaft.

I have never been to Singapore, but I understand its weather is generally more 'extremely tropical' than the most tropical parts of Australia; hence, Michael is contemplating 're-air conditioning' his 'new' D and he would welcome Forum members' suggestions on how best to tackle this, employing modern technology, notwithstanding that the subject vehicle is a DS23 auto approaching 50 years of age. I should add that I believe there are very few Ds in Singapore and very few mechanically-minded people conversant with them, but, I understand, no shortage of air conditioning specialists.

Michael has authorised my initiation of this thread and I expect he will contribute posts as appropriate as the conversation evolves.

Thank you, in anticipation.

Chris
 
The best possible suggestion I can make is ditch the York compressor in favor or a Sanden rotary compressor- far less of a shock load on the cam pulley. They're also cheaper and easier to obtain. Also, have a look at the Vintage Air website- they specialize in basic A/C units for hot rods, which was very much the type of system installed in a D. If I can find it again, there was also a company that had just recently started reproducing the fender-mount condensers- expensive, but you do now have the option. Considering how marginal the Ds cooling system was, removing thermal load from the radiator seems a good thing.
 
Having had a DS23 injection in the tropics one word to add to the above.. insulate, insulate insulate. The footwells of a late D are a heat sink and a heat trap. Ensure all the many holes in the firewall are sealed, especially around the steering column. Modern compressors ( and even a rotary style ) are a good move. The old York reciprocators are rough and vibratory and break camshaft pulleys AND their own mountings.
Having spent some time in Singapore, I concur a D would be horrific. The humidity is intense. I recall seeing a GS that had an A/C condenser fashioned and fitted under the boot floor, so some clever technicians exist there. An under dash fitment would be the more efficient than an, integrated "hidden behind the dash panel" design that we are used to now. Less heat sink to beat once it gets fired up. If commissioning a custom build, maybe even consider a unit mounted in the boot space, plenty of room, and locally ( OZ) developed CX systems used two evaporator units. Plenty of dead Toyota Crowns with split systems around to extract bits from.
 
1. Yes insulate....... BUT....
Don't insulate engine side of the firewall.
Airflow is the best method of getting heat out.
Dees have restricted airflow away from the engine as it is, don't make it worse.

2. Don't drive it off the camshaft.
I would consider a mod to the front of the gearbox, and drive it from an extension of the top (input) shaft, either direct, or by belt to the side.
 
fritzelhund said:
Having had a DS23 injection in the tropics one word to add to the above.. insulate, insulate insulate. The footwells of a late D are a heat sink and a heat trap. Ensure all the many holes in the firewall are sealed, especially around the steering column. Modern compressors ( and even a rotary style ) are a good move. The old York reciprocators are rough and vibratory and break camshaft pulleys AND their own mountings.
Having spent some time in Singapore, I concur a D would be horrific. The humidity is intense. I recall seeing a GS that had an A/C condenser fashioned and fitted under the boot floor, so some clever technicians exist there. An under dash fitment would be the more efficient than an, integrated "hidden behind the dash panel" design that we are used to now. Less heat sink to beat once it gets fired up. If commissioning a custom build, maybe even consider a unit mounted in the boot space, plenty of room, and locally ( OZ) developed CX systems used two evaporator units. Plenty of dead Toyota Crowns with split systems around to extract bits from.
Click to expand...
Had a friend who lived in Pasadena- Bob Sothan- who was literally a rocket scientist. An engineer for NASA at JPL. Anyway, his wife couldn't deal with the heat of the San Gabriel Valley during the depths of summer, so he devised a dual A/C unit for his D Pallas. After he passed away, Wally called me in to figure his system out (the car had been sold) and get it working again. After about a week of finding a multitude of problems (electrician, Bob was not!) Wally and I got it working again.

Once it worked as envisioned, you could use it as a meat locker.
 
ARCHRIVAL said:
bigger alternator and full electric a/c mod is available for ~$1500
Click to expand...
I've seen mention of these a bit lately... Has anyone had much experience with them?

I'm guessing an added benefit of this setup would also be that the compressor doesn't sap engine power while its running.
 
Tom_95 said:
I've seen mention of these a bit lately... Has anyone had much experience with them?

I'm guessing an added benefit of this setup would also be that the compressor doesn't sap engine power while its running.
Click to expand...

However the upgraded alternator certainly will sap engine power.

There is no such thing as "free" energy
 
Most 12v A/C compressors are very power hungry and typically draw about 100A, well beyond the 40A of most DS alternators. Electric vehicles get away with using them because the battery packs run at around 100v which significantly reduces the current draw.

The benefit to using one is that it can be mounted anywhere. Worst case scenario would be driving at night with the A/C on, headlights, windscreen wipers and maybe a radio. You'd need 100A for compressor, 16A for headlights, 16A for A/C fans and 4A for wipers and probably 4-10A for the radio which doesn't give you much left in a 150A alternator.

It's a good idea but worth keeping these things in mind. There are quite a few kits made for 911s that use them along with flat condensers under the floor. The other expense will be the 0 gauge wiring needed for the compressor.
 
If you have not discarded the original bracket for holding the compressor, you are way ahead of the game. The original AC required a special transmission bell housing and had a very sturdy bracket for holding the compressor and belt tensioner. You will, however, have to source or make a three-sheave pulley for the water pump to drive the compressor. Over the years lots of folks devised different ways to drive the compressor. I came up with a scheme in which the compressor is mounted in place of the alternator and the alternator mounted on top of the compressor, both on the left side of the engine. This obviated the need for the very rare three-sheave water pump. I believe Andre Pol (Citroen Andre) is reproducing the powered condensers that sit in the front fender wells. These were a big improvement over the condenser that sat in the radiator snout.
 
Hotrodelectric said:
Had a friend who lived in Pasadena- Bob Sothan- who was literally a rocket scientist. An engineer for NASA at JPL. Anyway, his wife couldn't deal with the heat of the San Gabriel Valley during the depths of summer, so he devised a dual A/C unit for his D Pallas. After he passed away, Wally called me in to figure his system out (the car had been sold) and get it working again. After about a week of finding a multitude of problems (electrician, Bob was not!) Wally and I got it working again.

Once it worked as envisioned, you could use it as a meat locker.
Click to expand...
I remember that car, if its the same one I am thinking about. It had a California coil to pre-cool the refrigerant before it went to the powered condensers in the fender wells.
 
citroenthusiast said:
I remember that car, if its the same one I am thinking about. It had a California coil to pre-cool the refrigerant before it went to the powered condensers in the fender wells.
Click to expand...
Yah and then evaporators front and rear. Oy weh! The biggest problem I kept running into was everything by the time the car sold, all the connections (seemingly thousands!) had begun to corrode. Hours upon hours of pulling, cleaning, testing.
 
citroenthusiast said:
If you have not discarded the original bracket for holding the compressor, you are way ahead of the game. The original AC required a special transmission bell housing and had a very sturdy bracket for holding the compressor and belt tensioner. You will, however, have to source or make a three-sheave pulley for the water pump to drive the compressor. Over the years lots of folks devised different ways to drive the compressor. I came up with a scheme in which the compressor is mounted in place of the alternator and the alternator mounted on top of the compressor, both on the left side of the engine. This obviated the need for the very rare three-sheave water pump. I believe Andre Pol (Citroen Andre) is reproducing the powered condensers that sit in the front fender wells. These were a big improvement over the condenser that sat in the radiator snout.
Click to expand...
I was skimming through I believe the Vintage Air site, and they had a mount adaptor, York-to-Sanden. They also have a few alternator mounts, but nothing I saw that would do as you suggest unless you piece it together. Considering how big the York is though, that's an interesting idea.

I knew the fender condensers were being repopped, just didn't know who. Figures it would be Andre.
 
Hotrodelectric said:
I was skimming through I believe the Vintage Air site, and they had a mount adaptor, York-to-Sanden. They also have a few alternator mounts, but nothing I saw that would do as you suggest unless you piece it together. Considering how big the York is though, that's an interesting idea.

I knew the fender condensers were being repopped, just didn't know who. Figures it would be Andre.
Click to expand...
I designed the brackets myself on the 3D printer, then once I had confirmed fit and function, I used the plastic brackets as templates to make them out of steel. Bandsaw and drill press was all it took. The mounting lugs on the top of the sanden compressor make a suitable hard point for the alternator support bracket.

SD508 in 67 DS Annotated.jpg
 
That's a lot of stuff hanging off the camshaft....... all driven by the cam chain.
I wouldn't do it.
 
All the more reason to have reintroduced the crankshaft pulley that DID appear on some 21 injections.
 
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