Does car Air Con vary in hotter climates?

[jeebus]

Sheepshanks said:

I remember having hire cars in the US is the past with a "hi" setting for the a/c but I don't recall having seen it for a few years.

This question comes up quite often on the Merc forums. People reckon they're the same worldwide, but the a/c in my C Class feels like it's only just coping and never feels cold as such. I'm sure it would struggle in hotter countries. Had it re-gassed (routine "servicing" of a/c is a complete scam) and it made no difference.

Make sure the condenser fan runs with the air con this could cause poor performance and is an easy thing to check.

[Cerbieherts]

A partially blocked pollen filter, collapsed receiver drier, non-working cooling fan, leak/lack of refrigerant or faulty flap operation within the HVAC unit all can cause poor operation. The trick is to pay someone who knows how an A/C system works and can diagnose it properly, rather than being a cheap arse and paying next to nothing to the many chains that claim lots and deliver very little.

[Sheepshanks]

jeebus said:

Make sure the condenser fan runs with the air con this could cause poor performance and is an easy thing to check.

I've had it from new and it's always been the same. It's a common complaint on Mercs that the a/c is never "icy" cold. It's adequate for the UK, I just struggle to believe the same system would be effective in places where towards 40C isn't unusual.

[Whistle]

I am on holiday at the moment in Florida and the air con on my hire car is miles colder than on our 2 cars at home.
After a while we have to turn it down a bit even though it's 34 outside.

[QROPS]

In Asia, quite a few of the cars come without a heater fitted, that's the only difference I could see since living here.

[caraddict]

In Norway, cars come better equipped for winter (heat up engine and coupe faster and front seats warmer is standard on all cars). When I lived in UAE most cars advertised "Gulf spec" which meant a better cooling setup for cars of extreme warm regions.

So there is definitely some differences for different markets.

[anonymous-user]

Yes cars spec'd for sale in the tropics are different, they do not have the heater element of the climate control system, they are pure air con cooling systems. But a lot of top end cars sold in Asia and Africa (MBW, Mercs etc) are actually European or Jap spec'd machines sold on the gray market and they have the European spec, Tropical ‘speced' cars tend to have bigger compressors etc. This has been true for years my 944 is a Malaysian spec car it only has air con and even after 25 years it is OK, again my Z3 does not have climate control like my British E38 had, but only has cooling, while my Lotus Carlton has the full European system with heater etc as it was a British spec car, the Carlton is currently have the air con upgraded and the tecies doing it cannot believe that the air con is so poor, thye are sizing up all the components

[Alucidnation]

I had used my folks 11 plate Renault Scenic for a trip to the South Of France In August 12, with temps in the high 30's and when the car was left in the sun all day when we were at the beach, the AC was blowing ice cold in less than a minute.

AS far as i can tell, that wasn't specced any different.

A few years before that we had an 05 Audi A4, and we had trouble stopping it being TOO cold, and then was in similar temps.

[HTP99]

Yes different countries have different spec A/C; the manufacturer that I work for if you tap in the chassis number or reg number into their system it will come up with the full spec breakdown of that car including which region A/C system is fitted.

Edited by HTP99 on Monday 21st July 09:33

[threadlock]

I've just returned from a 1700-mile road trip to the Alps. The AC in my XKR before I left the UK was never especially cold, to the extent that I started to wonder whether it needed a service.

When we got towards the Alps, though, the weather warmed up and the AC blew colder and colder air to the point at which my dad started to complain and my right hand on the steering wheel started to hurt in the cold air stream.

Same system, different ambient conditions. The weather in the UK probably hasn't yet been hot enough this year to require the full power of an AC system.

[Crosswise]

My last job was as an automotive AC Technician in Australia. The only difference I came across was that some Australian delivered cars were specced for hot climate. This would generally mean a bigger condenser and/or more powerful cooling fan. There was nothing more complex than that about it. All that really does is prevent the system reaching too high a pressure when the ambient temperature is very high, the output should be the same anywhere in the world. In developed countries everyone is using R134a, although that is about to change, SP34e is a mixture which will run at lower pressure, but it is really designed to replace R12 in older systems than to be used in new vehicles. R12 is still used commonly in many countries that care less about the environment than we have to, in my opinion it is a far superior refrigerant, but very hard to get hold of.

[DrDoofenshmirtz]

Evaporators evaporate better the warmer the ambiant air is circulating through them. So they blow colder.
It's got nothing to do with other countrys using better AC systems or simply feeling colder...they are actually blowing colder because it is hotter.
This is why you shouldent keep a fridge or freezer in a cold garage - it wont work as well.

[Alucidnation]

Interesting you say that, as my fridge freezer is nearly running 100% of the time in the summer, and when needed in the cooler months.

I would say that the efficiency is a lot worse in the summer.

[ATG]

DrDoofenshmirtz said:

Evaporators evaporate better the warmer the ambiant air is circulating through them. So they blow colder.
It's got nothing to do with other countrys using better AC systems or simply feeling colder...they are actually blowing colder because it is hotter.
This is why you shouldent keep a fridge or freezer in a cold garage - it wont work as well.

the evaporator is the cold bit inside the fridge. Putting a fridge in the garage means the fridges radiator is sitting in cold air and is therefore more efficient.

[redtwin]

That explanation makes the most sense to me. I have had a quick look regarding aircon part numbers for my car and they are the same for US and European models. There was no "Hot Climate" component option.

I also think it is the greater difference in atmospheric temp compared to air conditioned temp that makes it *feel* colder. Going from 21c outside temp into a 16c air conditioned car won't be as significant as going from 36c to 16c. A 20c drop in temperature is going to be much more noticeable than a 5c one.

[ATG]

Alucidnation said:

Interesting you say that, as my fridge freezer is nearly running 100% of the time in the summer, and when needed in the cooler months.

I would say that the efficiency is a lot worse in the summer.

is just having to work harder to maintain a greater temperature gradient. If it's warmer outside, the fridge has to work harder to cool the inside

[996TT02]

Pothole said:

also aircon should be serviced every two years and regassed every 5 at least. Hire cars are usually less than 2 years old so their systems will be in tip top condition. Unless you're comparing them with brand new or nearly new cars in UK, you're not comparing like with like, I'd have thought...

My '92 Landcruiser is probably on it's original gas and I have never ever done anything to it for as long as I have had it, and it still freezes your socks off. I use the aircon for around 4-5 mths a year.

There is not much that is serviceable except any blower filters which aren't technically part of the a/c system but shared with the heating/ventilation system. If the gas needs topping up, you have a leak, and that needs fixing. Anything else is fixing what is broken, and can't be prevented by "servicing".

Home aircon is the same, I have split units in almost every room and if you are sucker enough to pay for a "service" all they do is clean the filters, a simple DIY affair. We even had a unit from the '80s at a house we owned and it never needed anything else doing. On occasion startup capacitors fail on older units, but as previous, this is fixing what is broken. Never ever regassed any unit either.

[Thankyou4calling]

kapiteinlangzaam said:

So far, I have concluded from this thread that

a) Aircon is definitely the same the world over.

and

b) Aircon is definitely different in hotter countries.



Thanks PH!

OP here. All the answers are welcome but I just wanted the definitive. I'm no nearer now than at the beginning though I know a little more about fridge placement.

[redtwin]

kapiteinlangzaam said:

So far, I have concluded from this thread that

a) Aircon is definitely the same the world over.

and

b) Aircon is definitely feels different in hotter countries.



Thanks PH!

[Major Fallout]

In the 80's and 90's I know Rolls Royce fitted 2 air con systems to some of the Arab cars.