Lower temp or increase fan speed - which consume more FC?

[GravityBlue]

How does the variable displacement compressor knows how much to vary with manual control ? 

Its a much simpler concept.

Eg , u set at coldest temp at fan speed 1 , comp will run at max capacity.

Once reach low temp setting , control valve inside comp will self adjust operating pressure (internal bypass) to maintain that temp range , it will still continue running.

 

If set temp at 3~4 click up (from max cold temp) , assuming its at 22~23 deg , since no digital LCD to indicate temp.

Comp is actually running at max capacity , and it wont stop too. Just that heater flap is partially opened to mix hot & cold air , to achieve your desired temp.

 

The only way to save fuel is to achieve max coolness quickly , then off A/C but fan still running , switch on A/C when u feels slight warm. But u got to do it frequently in a cyclic action.

But what's the point of doing that , just to save a mere few CENTS ?

I only off A/C , when i need the extra horse during pickup , try that n u'll be amazed by the difference in pulling away.

 

Hope my limited knowledge on A/C helps.

[kdash]

If I am driving alone, usually I will set the about 23 degrees and the lowest fan speed with most of the air vents blowing at me.

 

Sufficient for me to cool down. 

 

for me, 25 deg and vary fan speed only. if really hot day and park under the sun then lower to 21 deg until car cools down then back to 25. 

[Kklee]

Its a much simpler concept.

Eg , u set at coldest temp at fan speed 1 , comp will run at max capacity.

Once reach low temp setting , control valve inside comp will self adjust operating pressure (internal bypass) to maintain that temp range , it will still continue running.

 

If set temp at 3~4 click up (from max cold temp) , assuming its at 22~23 deg , since no digital LCD to indicate temp.

Comp is actually running at max capacity , and it wont stop too. Just that heater flap is partially opened to mix hot & cold air , to achieve your desired temp.

 

The only way to save fuel is to achieve max coolness quickly , then off A/C but fan still running , switch on A/C when u feels slight warm. But u got to do it frequently in a cyclic action.

But what's the point of doing that , just to save a mere few CENTS ?

I only off A/C , when i need the extra horse during pickup , try that n u'll be amazed by the difference in pulling away.

 

Hope my limited knowledge on A/C helps.

 

How the compressor knows that it has reach the low temperature setting?

[GravityBlue]

How the compressor knows that it has reach the low temperature setting?

 

By pressure differentiate

 

[Kklee]

By pressure differentiate

 

 

That should be the method.  I am trying to understand how does the compressor knows when to vary? 

[Vidz]

one word - wind chill factor (erm.. ok 3 words)

 

the least energy to cool is with fan. it requires more energy to cool by compressor. like a bro mention use AUTO, cos you paid for the car and the car makers had already solved it for you.

[Simplecar]

By pressure differentiate

 

I thought temperature controls is by thermostat?

[GravityBlue]

I thought temperature controls is by thermostat?

That's true, applies to fixed type of comp.

For variable type, it serve as a second key to prevent icing, cos the control valve takes center stage.

[Dannnn]

So just use auto fan, n control the temp will do?

[RogerNg_185295]

So just use auto fan, n control the temp will do?

If the auto function is there, just use it

[GravityBlue]

Yupper , whether u set at 18 or 25 deg , comp works as usual.

Your desired temp setting is achieved thru heated air mix.

Even if A/C is off (comp at rest) , most significant gain is actually the torque gain (due to no load from comp).

 

With e exception of older car which uses fixed displacement comp without heater , some fuel saved if u set

at higher temp range.

[Kklee]

That should be the method.  I am trying to understand how does the compressor knows when to vary? 

 

@GravityBlue -  You have any answer to this?  Basically, the compressor can vary,  but when does it knows when to vary when there is no sensor or feedback? 

[GravityBlue]

@GravityBlue - You have any answer to this? Basically, the compressor can vary, but when does it knows when to vary when there is no sensor or feedback?

Before i compose an essay, can i know u in which trade?

If u r technically inclined, i shall use more chim terms ,if not will try to use simple/common description.

Btw, youtube is pretty informative.

Edited February 21, 2018 by GravityBlue

[Kklee]

Before i compose an essay, can i know u in which trade?

If u r technically inclined, i shall use more chim terms ,if not will try to use simple/common description.

Btw, youtube is pretty informative.

 

Admin.

I just want to know how the variable displacement compressor knows how much to vary without climate control. 

[GravityBlue]

Admin.

I just want to know how the variable displacement compressor knows how much to vary without climate control.

What's e problem bro, i had answered all your previous questios diligently .

But u give me the impression that u seems to understand / not so understand type.

So I'm trying to tailor my answers to your level of understanding, any wrong ?

[Kklee]

What's e problem bro, i had answered all your previous questios diligently .

But u give me the impression that u seems to understand / not so understand type.

So I'm trying to tailor my answers to your level of understanding, any wrong ?

 

You never really answer my question.

You only answer how the variable displacement compressor work - it varies using gas pressure / pressure differential 

My question is simply -  how does the variable displacement compressor knows when to vary ?

 

Let me then rephrase....what causes the gas pressure / pressure differential so that the variable displacement compressor varies?

 

My previous car has a V5 compressor but no climate control.

The V5 doesn't seem to vary because the temperature will go lower and lower at night. 

 

If you don't want to answer just say lor.  Don't ask me which trade I am in and try to tailor your essay and the next moment ask me what is the problem. 

[RogerNg_185295]

Anyone knows which will consume more FC?

What car you driving? Cos if u specify the model, the members here can advise better Edited February 21, 2018 by RogerNg_185295

[Hamburger]

Yupper , whether u set at 18 or 25 deg , comp works as usual.

Your desired temp setting is achieved thru heated air mix.

Even if A/C is off (comp at rest) , most significant gain is actually the torque gain (due to no load from comp).

 

With e exception of older car which uses fixed displacement comp without heater , some fuel saved if u set

at higher temp range.

Finally someone has come forward to say what I have been telling all these while.

 

Regardless of what you set, 18deg or 25deg, the air con comp works just as much. So just blast it at the coldest setting.

 

And if I find it too cold at times, I turn off the air con switch manually.

Before i compose an essay, can i know u in which trade?

If u r technically inclined, i shall use more chim terms ,if not will try to use simple/common description.

Btw, youtube is pretty informative.

Appreciate if you can fill in more with your knowledge.