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Discussion Starter #1
My original 1983 Texas registered (in 1984) 4 door RRC has original 'range rover' AC and it sucks (for Texas). It is working but not very powerful. I repaired the system (R134A conversion etc) a few years ago including a new Sanden compressor and now one of the original hoses has started to bulge and is leaking. Time for another look.

Did a bunch of research and found that the condenser technology (the radiator part at the front) has improved over the years so I am going for an upgrade. Changing to a modern parallel flow as large as possible (Vintage Air) Amazon.com: Vintage Air 037035 Parallel Flow Condensor: Automotive. Not all that expesive

The installation although original is clearly and early afterthought installation from Land Rover at the time. All parts are your typical US 1980's aftermarket. Some parts look pretty well designed, like the AC compressor bracket and the interior system, but others like the condenser mounting look pretty amateurish.

I have all the AC equipment at home (this is Texas) and was going to report my progress and findings for your entertainment:

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picture surgery for access, hopefully can remove without disturbing the radiator. To connect the new condenser I need to bend some fixed length piping (with fittings installed size 6 and size 8) which at least makes fitting much easier as you just crews it all together. Also need to make a new hose and will fit a new dryer. Add some oil etc.

It is so easy to get parts for custom AC installation with a large hot-rod market I a suppose

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Strangely there seems to be these cutouts which should help me remove and fit the condenser.

Also need to look at what to do with the fan. Single fan looks a little skimpy. Maybe install dual fans using some installation frame.
 

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Very interested in your results, I recently had my AC system rebuilt (R134A, new hoses, valve block, receiver/dryer, with original stock condenser and pump) and it definitely works, but it's not amazing. Running it full blast right from leaving the garage is enough to keep the car comfortable on an 85 degree day, but it struggles to cool an already hot car, and if the weather was any warmer it'd be fighting a losing battle even right from the beginning. I've got the cooling system sorted so that car doesn't overheat the desert, but I still do!
 

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Discussion Starter #4
Since this is a report (or 'blog') for your entertainment some more pictures and progress:
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Removal reveals my new-ish radiator which is doing sterling services. Never ever had any overheating issues with this monster.

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Some pipe bending action. These fixed pieces (12") connect the condenser with the hoses and pass by the radiator tank. I only had a 1/2" pipe bender so used some electrical spiral stuff to create the right thickness to bend the smaller (discharge) pipe.

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Pipes installed. The aluminium pipes on condenser are a little weak. To install the condenser I need to disconnect and fit the pipes separately which is a good thing because it means I don't need to remove the radiator. I bent the pipes on the old condenser a little (copper) to get it out.

Next I will install and then I need to check the PAG oil level in the compressors. Found this useful installation guide by Sanden http://www.sanden.com/productlibrary/manuals/SD_Service_Guide_Rev_2.pdf which has a procedure to check oil level. Currently I think I might have too much oil in the system which reduces the cooling capability. When I fitted the new compressor a year ago I went on the safe side..
 

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Ok some more progress over the weekend. I fitted the condenser with custom brackets at each side. Piping fits nicely between the radiator and the battery. Also changed out the hose between the condenser and the drier which had started leaking. Still waiting for the drier and also decided to buy a set of pusher fans to replace the single small fan that was there. I was thinking in wiring them in series to get 1/2 speed and less noise while covering the whole condenser.

I removed the compressor to check the oil level (drain and refill) I know I had too much oil in the system, but with the new condenser and drier requiring additional oil I was hoping my excess oil would suffice. I figured I needed 4 oz. The compressor was holding 4 oz so I put back 4oz of new oil and refitted.

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Should be able to finish this week, just waiting for Amazon deliveries now.
 

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Thanks for the update and all the pictures, this has been really informative!

However, I strongly recommend against running your fans in series. Doing so only allows 6V to drop across each fan, so the output is going to be 25% of the 12V power. The fan's internal impedance is a factor of the windings, meaning that it is effectively constant (for our purposes here we're ignoring back EMF, thermal effects, etc).

For V=IR and assuming a constant R, if V is cut in half (from 12V to 6V) then I is cut in half as well. This in turn means that the power output of the fan is cut by a factor of 4, meaning your 120W 12V fan is now a 30W 6V fan. We're going to assume a semi-linear relationship between power output and air volume (ignoring complex fluid flow effects, blade efficiency, etc), which means your 500 CFM fan now only moves 125 CFM. Therefore your two 500CFM fans in series only put out 250CFM total, which is half of what a single fan at 12V puts out. If you're concerned about the noise, It's better to put in a variable fan controller (which is PWM control, not voltage variable) that's either manually controlled with a knob/dial, or linked to a temperature probe.
 

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Hi LanceL,

Thanks very much good point. Yes some sort of VFD system might be easier indeed. My experience with fans is that at 'full tilt' they move a lot of air and make a lot of noise, while really the question is how much air is enough air cutting back on noise and power, so going parallel works might just be overkill.

I am going research fan speed controllers on Amazon now. Good thing is I can install them after the fact as an improvement.
 

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While a bit pricey, this guy makes excellent quality fan controllers, I have had one for a while (for coolant, not AC) and it does a great job of controlling fan speed, with full smooth variable control, not just a series of steps. It seems he makes an AC one now too, that's based on high side refrigerant pressure. He also responds to questions pretty quickly. (scroll all the way to the bottom, his website isn't the greatest)

 

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However, I strongly recommend against running your fans in parallel. Doing so only allows 6V to drop across each fan, so the output is going to be 25% of the 12V power.
Wait a second, wouldn't that be the case if they were wired in series?
When they are wired in parallel, they both see the full 12v tension differential. It's when they are in series that they need to share the tension drop and they end up working as 6v fans.
 

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Wait a second, wouldn't that be the case if they were wired in series?
When they are wired in parallel, they both see the full 12v tension differential. It's when they are in series that they need to share the tension drop and they end up working as 6v fans.
Yes it absolutely would be, thanks for catching that slip! When I was typing, I meant to write either "strongly recommend against series" or "strongly recommend parallel" and ended up writing "strongly recommend against parallel" which is completely wrong. Seems I need to proofread my answers better!
 

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No problem Lance, I only figured after I posted that's what you really ment.
 

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Discussion Starter #12
Ok update.

I completed the installation of the new (modern - parallel flow) condenser with two pusher fans and for sure it is much better. I presume the old one was just too far gone (like the radiator was). I can hold the condensor outflow pipe at idle with the two fans running. I have the two fans running at full tilt, in parallel, I am waiting for the PWM driver. The inflow pipe is HOT way too hot to touch.

I changed one hose as it was poor (leaking) and all the seals and the drier. I changed the oil in the compressor (PAG), pulled a vacuum and charged with two cans of R134a. I think it might take 3 but have not data on the system.

The cold air is cold (did not measure, but would say around 10 degC - 50F). Outside around 36deg C - 97F with 95% RM. The air flow of the inside fan is not spectacular, but went to the Lowes and car sat in the midday sun for 30 min or so. Cooled it down in about 5-10 min. No sweat on arrival home about 15-20 min drive.

The system (which looks to be original..) has two controls, fan speed and temperature. The temp control just cuts out the compressor when the evaporator gets too cold to avoid icing. Importantly the temp control is now cycling which in the past it would only do with an outside temp of about 23 deg C - 74F.

Overall a success!

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