ever replaced the lotus a/c unit with a jap one
Discussion
My 97 s4 a/c unit blows cold only occasionally(the heating is non existent) and reading your problems and questions on a/c units ive come to the conclusion the english dont know didly about air conditioning given their wonderful weather....not!
And i assure here in oz,on a 40 degree celcius day ,one can cook in a car.
Nevertheless im sure in some way or form the lotus ac unit can be replaced by a japanese one(honda,mitsubisi)etc.After all merecedes uses fujitsu built systems.If the germans can admit that the japanese build better ac units and the english cant ,maybe one of you have and id like to know about if we can do this.
I know it may sound like a silly question ,but nothings impossible especially with machines.If we can put porsche engines in vw beetles,theres bound to be someonewho has attempted to replace lotus ac units?
your comments please gentleman !
And i assure here in oz,on a 40 degree celcius day ,one can cook in a car.
Nevertheless im sure in some way or form the lotus ac unit can be replaced by a japanese one(honda,mitsubisi)etc.After all merecedes uses fujitsu built systems.If the germans can admit that the japanese build better ac units and the english cant ,maybe one of you have and id like to know about if we can do this.
I know it may sound like a silly question ,but nothings impossible especially with machines.If we can put porsche engines in vw beetles,theres bound to be someonewho has attempted to replace lotus ac units?
your comments please gentleman !
I think the problem is the lack of really trained AC people..
the calculations to design an AC system are fairly straight forward. A certain number of joules need to be removed from the car.
do do this a certain number of pounds per hour of refrigerant need to change state from liquid to gas..
THere is not a huge difference in the size of the system in any small car
the compressor has to pump and compress, the condensor has to turn it to liquid. the expansion valve has to allow the stuff to vaporise , the evaporator has to cool the air passing through it then the gas has to get compressed again. It is in fact a simple calculation and a symple system with very few moving parts..
putting in a different system would require some calculations to get it right... i think the best solution is to get the factory system set up properly...
if you are not leaking and the compressor is working the next biggest issue is getting the expansion valve working right.. there is not much else to go wrong.
just some thoughts...
Bruce s4s
the calculations to design an AC system are fairly straight forward. A certain number of joules need to be removed from the car.
do do this a certain number of pounds per hour of refrigerant need to change state from liquid to gas..
THere is not a huge difference in the size of the system in any small car
the compressor has to pump and compress, the condensor has to turn it to liquid. the expansion valve has to allow the stuff to vaporise , the evaporator has to cool the air passing through it then the gas has to get compressed again. It is in fact a simple calculation and a symple system with very few moving parts..
putting in a different system would require some calculations to get it right... i think the best solution is to get the factory system set up properly...
if you are not leaking and the compressor is working the next biggest issue is getting the expansion valve working right.. there is not much else to go wrong.
just some thoughts...
Bruce s4s
My observation is that it blows cold at highway speed, but in stop and go it starts lacking. I think it is a question of air flow over the condensor coil. I think that a small-ish pusher fan on the condensor would help a lot with the stop and go cooling. People with charge coolers would get the added benefit of more air over the charge cooler coil as well. Just a theory.
Dr.Hess
Dr.Hess
my esteemed colleagues let me first apologise for my ruefull spelling!I cant thank you enough for your quick replies which have ,in the very least invigorated me to consider attempting to achieve this task of fixing ac/heating problems once and for all.Benfell,i believe it is possible.growing up in malaysia my father had a 73 opel record but installed a jap ac system under the dash that was so instantaneously cold that it could cryogenically freeze the nads off a bull elephant in seconds and hence my train of thought regarding my 1 day old dream lotus.Money is a consideration ,but relative to the overall cost of the car ,the ac unit can make a significant difference to appreciating or hating the achivement of a life long ambition.(owning a lotus).This is not quite unlike having a leaky roof on a newly purchased million dollar house .Its always the small things that make the biggest difference.(im in property development,just in case).So ill budget accordingly.Bo jangles your technical knowledge is formidable and overwhelming for a heathen like myself,nevertheless comprehensible.But you answered the nagging feeling i suspected so succinctly when you said you just had to get" the factory system right" and thats just where the problem lies .I dont think lotus ever got the factory system right atleast not 100 % of the time where the japanese have, 110% of the time with reliability too!
Dr hess ,the air flow problem has more than a hint of being right but it still boils down to poor design by lotus so why push a car up hill and try to fix an unreliable ,incompatible design when one could be better off by starting with a clean slate and accepting a near perfect japanese system.
Maybe its my boyish and new enthusiasm or im high on fuel smells within the cabin(to be resolved soon)! but as god as my witness gentleman ,i will attempt this quandry and keep you informed.I may fail but should i succeed just name the lotus ac systems problems ,"Prax cooling's syndrome"
kind regards
prakash
Dr hess ,the air flow problem has more than a hint of being right but it still boils down to poor design by lotus so why push a car up hill and try to fix an unreliable ,incompatible design when one could be better off by starting with a clean slate and accepting a near perfect japanese system.
Maybe its my boyish and new enthusiasm or im high on fuel smells within the cabin(to be resolved soon)! but as god as my witness gentleman ,i will attempt this quandry and keep you informed.I may fail but should i succeed just name the lotus ac systems problems ,"Prax cooling's syndrome"
kind regards
prakash
Dr. Hess, are you suggesting that additional fans above and beyond the normal cooling fans? My a/c works great but leaves a bit to be desired when in stop and go traffic. I wonder if additional airflow over the condenser will help that? Where do you suggest they be mounted?
John
94 S4
John
94 S4
Hey Guys,
This is just my theory based on observations of my 89 non-SE and other people's cars. Common themes are that the cooling is OK when you are moving, but barely there when you are stopped. This, to me, indicates an air flow problem over the condensor. Even if you upgraded everything else in the AC system to the latest as found on Toyota's, etc., you still are going to have low airflow over the condensor at stop and likely poor cooling. The heat has to be dumped to get cold AC, and if there is poor airflow over the condensor, the heat is not going to be dumped. So, I think that if you put a pusher fan on the front of the condensor, wired in to come on with the rest of the fans or by a separate switch, you would find the stopped AC to be much improved. As I understand that SE's have a combination charge cooler radiator and AC condensor in one, putting a pusher fan in front could only help lower the charge temps too.
Toyota KP Starlets came with a small, thin pusher fan stuck on the radiator with little plastic thingies that went through the fins. I think something like this would work. It would be a PITA to put in, dropping the radiator units, etc., but I think it would be worth a try. A small fan like that can draw more than 5 amps or so, and I think the fan circuits could handle it easily.
Dr.Hess
This is just my theory based on observations of my 89 non-SE and other people's cars. Common themes are that the cooling is OK when you are moving, but barely there when you are stopped. This, to me, indicates an air flow problem over the condensor. Even if you upgraded everything else in the AC system to the latest as found on Toyota's, etc., you still are going to have low airflow over the condensor at stop and likely poor cooling. The heat has to be dumped to get cold AC, and if there is poor airflow over the condensor, the heat is not going to be dumped. So, I think that if you put a pusher fan on the front of the condensor, wired in to come on with the rest of the fans or by a separate switch, you would find the stopped AC to be much improved. As I understand that SE's have a combination charge cooler radiator and AC condensor in one, putting a pusher fan in front could only help lower the charge temps too.
Toyota KP Starlets came with a small, thin pusher fan stuck on the radiator with little plastic thingies that went through the fins. I think something like this would work. It would be a PITA to put in, dropping the radiator units, etc., but I think it would be worth a try. A small fan like that can draw more than 5 amps or so, and I think the fan circuits could handle it easily.
Dr.Hess
Yeah I see what you mean but I am wondering how much additional flow that would give since there are fans already pulling through. I know it would be an increase, but would it be enough to notice a difference? I have often thought about installing an engine compartment fan like the earlier cars had. It just gets so darn hot in there I would think that would help too. My plans this winter are too wrap the exhaust and turbo to cut down on the engine compartment heat, so I may try an additional fan or 2 as well.
John
94 S4
John
94 S4
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