Just what IS "Climate Control"

I'm in the market for a cheap vauxhall, and am somewhat confused as to the difference between Air Conditioning, and Climate Control. I assumed that CC was a derivative of AC with a closed-loop control system, however, it seems the lower-spec'd cars come with CC, whilst the higher speced come with AC/CC - suggesting the former doesn't have AC.

So, my question is - just what is Climate Control, and what is its relationship to Air Conditioning.

...and to keep it on topic with uk.rec... is there anything I should be wary of when checking out CC and/or AC equipped cars? - obviously - does it get cold, but anything like service intervals / gassing frequency?

Mike

Reply to
Mike Dodd
Loading thread data ...

On AC you turn it on and it's on - when you turn it off, its off. With CC, you turn it on, set a desired temperature, and the CC will run until it hits that temperature, and then turns itself off, until the temperature rises (or falls) and then turn's itself on again until it reaches the desired temperature and then turns itself off, etc etc etc. That's how mine works anyway.

Reply to
Layezee

Mike Dodd (no-address@lo0) gurgled happily, sounding much like they were saying :

A moving target.

Aircon is easy to define. It's the setup with a compressor/condensor/evaporator and a cooling gas which works like a fridge to cool and dry the air passing through the heater box.

Climate's more tricky. It's sort-of-a-range of functionality ranging from automatic control of the hot/cold airflow thermostatically to maintain a set temperature through automatic control of fan speed and air flow direction.

If the heater controls are red->blue, then it's not climate. If they're marked in degC, then it's sort-of-semi-auto-climate. If there's an "auto" button/setting for the fan and flaps, I'd call that climate.

Indirect. Climate is usually fitted with aircon, and usually auto-controls the aircon - there may be an "ECO" mode that turns the aircon off.

Check the air changes direction properly, check the temperature control works properly. Aircon needs using regularly, else the seals shrink and the gas leaks. If the aircon doesn't cool readily or clear misty windows in wet weather, then it's probably empty - and that could get expensive. It might just need a sub-£100 refill, it might need new and expensive bits.

Reply to
Adrian

Others have given you the technical background. I'll comment on safety aspects on a top of the range car fitted with "Climate Control". Was driving along when summer rain turned into a really heavy storm requiring headlights, wipers etc. Climate control was doing its stuff, and visibility was fully adequate for driving. After about 5 minutes and with no warning whatsoever, the air conditioner cut out, and virtually instantly the windscreen misted up making me "blind". To add to the confusion (I was driving in traffic.), warnings started flashing from the control, and I needed a duster to clear the screen. If you have working Climate Control, a duster is not the sort of item that you're likely to have in a convenient place! It was a pretty scary situation. Having pulled in, it proved impossible to get the fan to work by itself, so sat at the roadside and waited for the storm to clear. (Prior to this event the Climate Control had given no warnings whatsoever that it might throw a tantrum and disable the fan.)

Since then, I've steered clear of Climate Control and am much happier where the A/C is independent of the normal heater/demister fan and controls. I did take up the matter with the importers HO but they didn't really want to know.

Reply to
Malcolm Stewart

It's both under the control of one microprocessor. So set the temperature to what you want and it will either heat or cool the car as required. Depending on complexity, it will also control the humidity and look at the quality of the incoming air and swap from fresh air to re-circulating automatically. They should all include pollen filters.

In auto mode on a cold day, mine also starts off with the fan at very low until the engine starts producing heat. Then ramps up to get the interior to the correct temp as fast as possible. Then slows to a quiet setting. And then switches on the fresh air face vents.

If the day is hot, the blower will come on full, since AC works as soon as you start the engine. It will then ramp down to normal as the required temp is approached.

However, you don't have to use auto mode and have complete manual control over all the functions if you so wish.

Reply to
Dave Plowman (News)

On my BMW you have full manual control of the CC if you wish. And in that mode the two are entirely separate. But even in auto, you have the option of heating only.

Reply to
Dave Plowman (News)

The dehumidifier is, arguably, the best feature of CC as misted up windows clear _very_ quickly - even when the engine is cold - and the car is less prone to misting up in the first place; I regularly see SWMBO's car, which doesn't have AC/CC, misted up when parked on the drive but mine is completely clear.

Good explanation. Mine does a neat trick when you start up on a hot day, it first directs the air to the screen only, then it opens the footwell vents as well, then turns off the screen, turns on the face vents, then finally turns off the footwell vents. All this happens with the fan on full tilt and takes about 20 secs. The idea is to "flush out" pockets of stagnant hot air.

Parish

Reply to
Parish

Dave Plowman (News) ( snipped-for-privacy@davenoise.co.uk) gurgled happily, sounding much like they were saying :

It's still all controlled by the same ECU, though.

Reply to
Adrian

Yes, but ECUs rarely fail. How often has your computer one gone down?

Now older cars with all the servos vacuum operated...

Reply to
Dave Plowman (News)

CC: You leave it alone except for setting your preferred temperature and it sorts itself out.

Manual control is available but rarely used.

AC: Gives you the option of cooling continually or not, some cars give you the option to run heater as well to give good demisting/comfort.

mrcheerful

Reply to
mrcheerful

Dave Plowman (News) ( snipped-for-privacy@davenoise.co.uk) gurgled happily, sounding much like they were saying :

Umm, actually - it has. Terminally. Rescued only by using a good used one out of a scrapper. The actual chip doesn't die, but the fan power transistors do, as do the connections on the PCB.

The flap motors also play up.

Ah, proper Saab 900s - turn the heater knobs, and listen to the wheezing and sighing and groaning...

Nothing gaffer tape won't fix.

Reply to
Adrian

I dunno, but if BMW have any sense they'd use ARM processors for this sort of thing which don't try and imitate the sun...

Reply to
Dave Plowman (News)

Same on my Volvo 850 and Wife's Volvo S40, both with climate (and AC manual override), and on both "windscreen" mode forces the AC on regardless of whether it's required for cooling or not.

Alan.

Reply to
Alan

It's the same with manual air-con in the Volvos - my S70 turns on AC when you turn the air-distribution up to the windscreen.

Reply to
Douglas Hall

Good point, well made.

Oddly, though, I've seen numerous people with CC equipped cars, treat them as if they were manually controlled ventilation systems.

Ideally, but I've known some people who either don't seem to get that, or just feel the need to constantly dither with the settings.

When I've had cars with CC, that was the beauty to me - set the temp, never worry about it again.

Reply to
Douglas Hall

Well I find that bit a little debatable. Once I've used aircon to clear misty windows (eg in damp weather), I find I then pretty much have to use it on and off for the rest of the journey (you tend to get some moisture build-up on the evaporator, when you've run the aircon).

Reply to
Douglas Hall

that will happen of course if you turn the AC off as it won't be dehumidifying the ambient air.

I did say the best feature of CC, not AC, which (assuming you leave it on auto) cools/dehumidifies the air before heating it.

Parish

Reply to
Parish

I think all I meant to point out, being that using the AC to dehumidify is good, but then tends to make you dependent on it for that journey. Clearly CC masks that, because it's one and off with the AC as it's want.

Reply to
Douglas Hall

Sorry, misunderstood what you were saying.

Parish

Reply to
Parish

Ahh, you know my wife then !!

mrcheerful

Reply to
mrcheerful

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.