As you may know I'm converting my 4x4 RS500 to air con, I have the bulkhead panel and blower/evaporator unit organised but am pondering on which direction I should go with regards the air con rad as I'm going to use a 500 sized intercooler.

I'm hoping to draw on personal experience and/or actual facts, anyone carried this out on a Sierra or Escos?

I have read some previous threads and noticed that the original cars used R12 refrigerant rather than the newer 134a and that the later gas requires a larger compressor (user foreignRS mentioned it) to produce the same performance as the earlier type. I don't mind adapting a later compressor, does anyone know any units that are better than others size for size? I have late compressors from Audi (VAG), Rover and Fords so would like to use one of those if possible.

Any info would be a help

 

i know you cant get the R12 gas anymore. Im sure ive heard someone say if you change all the seals in the R12 system you can use the R134 gas. I could be wrong though.

 

Mart what the fook were you doing up at 4.12am?

 

Wot refrigerant was used it the escorts cosworth

All so i will ask at work to day for you . as we do air for a liveing but big stuff running on R407C AND R410A and retor fitting the old R22 units i will see wot i can find out for you . when you need it preshering/vacing/gasing up my work mate has the kit to get on to a car a/c so i should be abull to help you out there mart

 

Mart...... Keith @ KM Accoustics had two small aircon rads made up for his Escos and mounted them behind the bumper on either side linked up, worked a treat.....

Would think any of the new generation pumps will work fine, just need one with the std 12V solenoid actuation... I know the MK3 Mondeo/Focus units are very efficient for their size

 

You can use R134a in an R12 system. No seals need changin'. Just the feed nipple. You will lose %30 cooling and can make up for this with a much larger condenser.

Or buy some Duracool and get ultracooling better than factory. I ran this in my Scorpio and it like the arctic in there. The Duracool molecule is MASSIVE and you will see very,very little loss over the years. It just can't escape like R134a can with its tiny molecule.

http://www.duracool.com/

I'd ship you some of this Martin. It's cheap over here. Hundred pounds worth (including shipping) would do the entire car along with leak stop and new lube. I highly recommend this stuff and it works ACE in Ford systems.

 

Job Done....

 

A bit of info.. I have checked a couple of customers cars and the stickers on the slam panels say that the N plate Escos uses 134a and a K plate Sapphire says R12.

 

indeed i was going to say exactly the same thing, works very well

 

I will email Keith for info, thanks.

 

Martin

Mike Rainbird's friend Ben Cresswell installed aircon on a Sapphire that had a non-aircon shell.

Mike might be able to put you in touch with him ( Ben is very good at the electrics side of stuff from what I gather )

Cheers

 

i was wrong again sorry.

 

Mike already gave me his bulkhead photos, thanks though I have a the panel ariving tomorrow.

On the look out for an Escos pump now, anyone? No piss take prices!!!

 

In the wide awake club

 

the 134 gas isn't as efficient as the r12 so it doens't cool as much

then there are different gasses which don't work so well when they are cold (working with fridge vehicles tends to show up loads of issues)

as far as the rad is conserned, there are several fixing points in the chassis so i'm sure you can trial fit the orignal, or, if that doens't fit, you can check out various different other rads

don't use the granada one, it will sit way too high/low as the mounts are in a different palce

 

I have the complete AC system from a November 1991 XR4x4 sitting in my garage and taking up space. It was working when removed but that was years ago so I don't know if the compressor or anything else has seized. From memory the a/c radiator is ok.

I meant to skip it at Christmas but the snow put a stop to that!

Let me know if some/all of it is any use and you can have it for the price of postage & packing (if you want to give me a Guinness for it, I won't argue!)

 

Martin,

My Sapphire has a a 500 cooler with Aircon. From memory, they used a slim Jaguar radiator. If you are in the area (London), you are welcome to have a look and see how they have done it...I am sure it will make more sense to you than me trying to explain it...

Narinder

 

Thanks for that but I'm looking for a later pump with multi V drive rather than the single V.

Hi Narinder, long time.. I'm not very often in London at sociable hours, does your air con rad fit in from of the 500 cooler? Have you monitored charge temps to see if that arangement is effective for charge temps? Any pics with the bumper off?

 

Hi Martin.

I have 12 years experience of working as an Application Engineer and Test Engineer for the world's largest automotive supplier, so I know a little about these things. I would've said that using a system designed for R12 with R134a would result in a decrease in performance as R134a needs more condensing capacity than R12.

Increasing to a larger compressor will not necessarily improve performance as it can lead to longer off times from temperature cycling due to the evaporator getting too cold oo quickly.

The 'radiators' are not as simple as water radiators. They are condensors and their function is to remove the heat energy that is put into the refrigerant by the evaporator and the compressor. Firstly they do this whilst the refrigerant is in a superheated gas state, and then they cool it further (at the same pressure) so that it condenses into a liquid. Hence the name condenser, not simply radiator. So 2 cores that are the same physical size as one larger one will not necessarily work in the same way. It's all relative though, and whilst most a/c systems are designed to cope with arizona/australian climates, yours won't need to be specced up perfectly to achieve that level of performance.

If I was you, I would find a compressor of a vehicle that is more efficient than the shitty ford compressor and has a suitable pulley arrangement for where you want to mount it. You have to be careful in selecting a newer one though, as many of them have built in capacity regulating devices that may not be well matched to the rest of the system (as they sense the high and low pressures and match a low side pressure drop to an evaporator temperature). I would stick with a fixed displacement compressor like a Sanden SD7H15 as this can be cycled on and off to meet demand using the standard wiring loom.

On the condensing side I would go for a solution that places it away from the intercooler/radiator stack as you really don't want air off the condenser going over your intercooler or vice versa. Perhaps the best solution is a thick intercooler core that covers the top half of the rad, and a condenser core that covers the bottom half. You will find that whenever a/c is running it needs lots of airflow, so that means more powerful fans than standard, especially trying to force the air through thick cores. Sealing with closed cell foam between heat exchangers is also a good idea to make sure all air is forced through all cores.

Hopefully this will have given you some food for thought, but if you have any specific questions then just ask. if you need any parts, I would suggest dealing with http://www.compressortech.co.uk/ that are local to you.

 

Good info Nick, thanks How can I tell if a compressor has a capacity regulating device?

 

First of all, you need one with an electromagnetic clutch as some electronically controlled regulating compressors don't have them but most other regulating compressors do, so that's not much of a clue. Different manufacturers have different labelling and naming conventions but Sanden compressors have a V in the name and usually say 'variable displacement' on the label. For other manufacturers you'd have to reseach on the net or give Jim McClean at Compressortech a call.

There are literally hundreds of different poly vee pulley arrangements available with different diamters for different speed ranges and crankshaft pulley sizes (you don't want to overspeed them, but running them as fast as possible gets the most performance from them) as well as different widths of belts (4 to 10 grooves) and different belt offsets.

If you want to use a compressor made for R12 with R134a, you can without problems as long as yo flush out all of the old oil and replace it with oil suitable for R134a as the old type of mineral oil does not mix with R134a and may not find it's way around the circuit back to the compressor again.

 

I use r413a as a drop in replacement for r12.