Question - If the AC in the car is making you too cold and you turn
the temp dial to "warmer" to make the air coming out less cold will
that make the AC work harder and make your gas mileage worse? Why?
NO. it just moves a door to mix in some warmer air. Aside from that,
the AC in cars today is very efficient and makes little difference to
the mpg. Comfort is more important that a tiny difference in fuel cost.
All my smaller cars show acceleration decrease with compressor on.
An older car of mine, the temp slider controlled the thermostat off the
evaporator. Never liked door mover systems. I'm going to assume, climate
control also uses the thermostat method. The moving door technique should
limit the air going through evaporator, thus limiting compressor usage.
There are virtually no "throttled" systems any more - and have not
been for decades. The compressor turns off and on th controll
pressures - and therefore heat transfer. Virtually all climate control
systems use "air blend" technology
Some systems used fixed orifice, some use an automatic orifice, and
some use a temperature controlled expansion valve TXV) which senses
the temperature of the evaporator and controls the amount of
refrigerant allowed int the evaporator to prevent icing etc. There is
also something called an "expansion block"system
The AC system controls the pressures and temperatures of the
refrigerant for most efficient operation - the blens doors control the
temperature of the air inside the vehicle. Newer compressor and
control technology improve the efficiency.
I don't understand climate control.
If i get in the car and it's cold, am I supposed to leave the temp set
to, say, 70, and the heater will put out very hot air until it gets
(close to???) 70 and the temperature of the air will (slowly???)
decrease and be only warm when the sensor says 70?
It seems to me the air is never that hot unless I turn the temp up to
80, and that if I leave it on 70, it will take forever to warm up, but
I'll admit I haven't kept tabs that closely.
I also don't like the Toyota climate control because it keeps changing
whether i get outside air or not. You would think whatever setting it
had when I turned the car off would be the setting when I turn it back
on, but No. (I think it depends on the outside and inside temps,
but knowing for sure would mean detailed records. )
On Thursday, February 25, 2016 at 8:33:27 AM UTC-5, Micky wrote:
That's how all the ones in the cars I've had worked. When there is a
big temp difference, the heater valve is full open and the blower is
on a high speed. As it gets closer to the set temp, the heater valve
is either cycled or partially closed and the blower speed decreases.
On Thursday, February 25, 2016 at 10:06:31 AM UTC-5, trader_4 wrote:
I've got one vehicle with automatic climate control and three without.
When driving the vehicles with just the 3 basic controls (fan speed,
temperature and mode) there needs to be some tweaking done occasion as
conditions change, such as sunshine, outside temperature, etc. I'm
talking about during a given driving session, not day-to-day.
When driving the vehicle with the fully automatic climate control,
there needs to be some tweaking done in occasion as conditions change,
such as sunshine, outside temperature, etc. I'm talking about
during a given driving session, not day-to-day.
In other words, there is no such thing as "set it and forget it"
in any of the vehicles, automatic or manual. The automatic climate
control is not like a house thermostat where it maintains fairly
consistent conditions. There are too many variables associated with
a moving vehicle for the climate control system (at least mine) to
be a completely hands-off system.
I've got nothing against new technology, in fact I'm in favor of
automating as much as my life as possible. However, in my vehicles,
I prefer the 3 basic controls. If I'm forced to tweak things anyway,
I'd prefer basic, simple to use controls.
On Thu, 25 Feb 2016 08:54:57 -0800 (PST), DerbyDad03
Hmmm. AFAIK, the automatic is on all the time, with no way to turn it
off, and yet I don't think it's ever made the fan run faster (even
though the fan speed control is electronic and it could). That's good
actually, because I'd rather be cold a little longer than have to
listen to a louder fan. (IIRC, the Lebarons had 4-speed fans and the
first 3 speeds were quiet enough not to bother me. This Solara has a
5-speed fan, whoop-de-do, and only the first 2 speeds are quiet.)
But otherwise, your explanation is what I expected.
I guess this answers it. A friend with a Lincoln Town Car warned me
not to get automatic, but I like high-end cars and most convertibles
come with automatic AC, so I had no choice.
Me too. It also turns the AC on whenever I turn on the defrost, and I
know that helps a bit but I still have to turn it off. The worst
problem lately is the indoor/outdoor air setting.
I'll keep this in mind for the next cars but I'm not optimistic.
Thanks, both of you.
Almost set in and forget. Even between driver and passenger seats
depending on sun shine or shade they adjust the difference. What
I like in auto climate control is, even if very cold outside as soon
as I drive I can get warm air. Even prewarm the windshield to prevent
fogging. For this I have to push one more button and leave it. Heat/Cool
seat, steering wheel, sync'ing front and rear seat temp. settings, etc.
I beg to differ. My last two cars (2013, 2015) have been amazingly
accurate. Once to temperature, they take care of any adjusting for sun
load, humidity, whatever. I never touch the controls all winter or all
summer when I keep it a few degrees warmer.
My present car I bought on Sept 28. I adjusted the control the next day
and have not touched it since. My wife a couple of times has turned up
the temp on her side, but I just set it back by touching the sync button
when she it not with me. My last car was the same. I do recall a couple
of older cars where I did twek a bit though.
Oh, it also turns the defroster on when needed too. Only once did I do
that manually. It senses the windshield ready to fog.
Only thing I do when the car is still cold is turn on the heated seats
and heated steering wheel, but after 10 minutes, I turn them off too.
It kept the temperature just as good at 12 below too!
On Thu, 25 Feb 2016 11:58:53 -0800 (PST), DerbyDad03
My 02 is pretty consistent too. (Ford) The '96 Mystique was good too.
So was the '88 New Yorker. Even the climate control on the 85 LeBaron
was pretty good - but on the 2600cc 4banger you could feel when the AC
Tinted glass helps - - -
Also the fact that MOST higher end vehicles with climate control have
a sun load sensor that acts a bit like an anticipator
That's one thing a 14 year old car can't do - - -
On the Taurus we have to turn on the read defogger - and that also
heats the mirrors. The seat gets slowly warmed by the hiney sitting in
it, and gloves handle the cold steering wheel.
On the 20 year old Ranger with McGiver AC I have full control over
when the AC runs and I sometimes turn it on to help clear the
windshield. The fact it only has rubber mats helps reduce fogging on
the inside of the glass. (doesn't hold moisture to end up as vapour on
Do. It should reach 70 in the same time regardless of what temperature
(70 or above) you have it set for. There MAY be a small difference,
but on my Ford I have never noticed it. My wife likes to fiddle with
the settings because she THINKS it will warm up faster, and BELIEVES
it does, so she FEELS it does. What really happens is it just gets
warmer, so SHE warms up faster.
You get outside air ALL the time with a Toyota climate control system
UNLESS you set it to MAX AC. The system will never restart in MAX AC
mode by itself, nor should it. The system is most efficient in the
Outside air is NORMAL AC. It is also NORMAL HEAT. Without outside air,
particularly without the AC working, the humidity builds VERY quickly,
the air gets stale, and the car starts to smell like a dead man's
arm-pit. Not to mention the carpets stay wet, the windows fog up, and
the car, generally, becomes unpleasant.
On Thu, 25 Feb 2016 13:20:09 -0500, email@example.com wrote:
I'd like to say that I will try, but the engine doesn't even get hot
for 1/4, 1/2 mile and by then I've forgotten everything I was thinking
when I got in the car. But I'll try to try.
Not this one. I used to leave it on outside all the time (I never use
max AC, fan is too loud) but there's some leak dripping oil somewhere
hot and the smell was entering the car, so now it's supposed to be on
inside all the time, and the smell is gone. I suppose some small
amount of outside air could be coming in but it's not enough to smell
the oil. When I tried to leave it on Outside, I guess that was when
it kept switching to Inside. Keeping it on Inside, it doesn't switch
on its own as mch, if at all.
But when I fix the leak I'm going back to Outside, and it's going back
to arguing with me.
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