Cooling fan is always running this summer
 

"gutermuth2000" > wrote in message
news:1_634408_510522338dd205e89750f55f9eb6d7d1@aut oforumz.com...
>I was wondering if my fan clutch was bad in my 2000 323.
> It runs all the time and just seems to be sucking power under hard
> acceleration. Does anyone know at what temp. the clutch starts
> turning the blades? I was hoping that the temp. outside (since its
> been in the 90's) is the cause and when the weather cools down it will
> stop.

the clutch-fan in my truck doesnt kick in until 200 or so.

When the car is OFF (and cold) can you spin the fan by hand?

In article >,
says...
>
> "gutermuth2000" > wrote in message
> news:1_634408_510522338dd205e89750f55f9eb6d7d1@aut oforumz.com...
> >I was wondering if my fan clutch was bad in my 2000 323.
> > It runs all the time and just seems to be sucking power under hard
> > acceleration. Does anyone know at what temp. the clutch starts
> > turning the blades? I was hoping that the temp. outside (since its
> > been in the 90's) is the cause and when the weather cools down it will
> > stop.
>
> the clutch-fan in my truck doesnt kick in until 200 or so.
>
> When the car is OFF (and cold) can you spin the fan by hand?
>
>
>

I wonder if this is related to a problem we've been having with the AC
on our '98 Z3 convertible, 2.8 litre. We cannot turn it completely off.
Instead of having 0 1 2 3 4 as controls, it gives us 1 1 2 3 4, so there
is always cold blowing. Other than that, it works great! Even when the
outside temp is 90 to 95, the air is chilling in the cockpit.

And yes, I can move the fan by hand when the engine is off and cold.

On Sun, 24 Jul 2005 07:16:08 -0400, Shadowdancer >
wrote:

>I wonder if this is related to a problem we've been having with the AC
>on our '98 Z3 convertible, 2.8 litre. We cannot turn it completely off.
>Instead of having 0 1 2 3 4 as controls, it gives us 1 1 2 3 4, so there
>is always cold blowing. Other than that, it works great! Even when the
>outside temp is 90 to 95, the air is chilling in the cockpit.

Most cars' blower motor controls are set to run the fan at low speed
all the time while the AC compressor is engaged. It's done to keep
air flowing through the evaporator matrix to prevent ice from building
up on it. I bet the fan will go off completely if you turn off the AC
button.
--
Dan.

In article >,
says...
> On Sun, 24 Jul 2005 07:16:08 -0400, Shadowdancer >
> wrote:
>
> >I wonder if this is related to a problem we've been having with the AC
> >on our '98 Z3 convertible, 2.8 litre. We cannot turn it completely off.
> >Instead of having 0 1 2 3 4 as controls, it gives us 1 1 2 3 4, so there
> >is always cold blowing. Other than that, it works great! Even when the
> >outside temp is 90 to 95, the air is chilling in the cockpit.
>
> Most cars' blower motor controls are set to run the fan at low speed
> all the time while the AC compressor is engaged. It's done to keep
> air flowing through the evaporator matrix to prevent ice from building
> up on it. I bet the fan will go off completely if you turn off the AC
> button.
>
Yes, it does go off if you turn off the AC.

Thanks!

In article >,
Dean Dark > wrote:
> Most cars' blower motor controls are set to run the fan at low speed
> all the time while the AC compressor is engaged. It's done to keep
> air flowing through the evaporator matrix to prevent ice from building
> up on it.

Eh? It gets hot, not cold. ;-)

--
*We waste time, so you don't have to *

Dave Plowman London SW
To e-mail, change noise into sound.

Dave Plowman (News) wrote:
> In article >,
> Dean Dark > wrote:
>
>>Most cars' blower motor controls are set to run the fan at low speed
>>all the time while the AC compressor is engaged. It's done to keep
>>air flowing through the evaporator matrix to prevent ice from building
>>up on it.
>
>
> Eh? It gets hot, not cold. ;-)
>

Nope. Evaporator gets cold...

<http://home.howstuffworks.com/ac3.htm>

-Fred W

In article >,
Malt_Hound > wrote:
> >>Most cars' blower motor controls are set to run the fan at low speed
> >>all the time while the AC compressor is engaged. It's done to keep
> >>air flowing through the evaporator matrix to prevent ice from building
> >>up on it.
> >
> >
> > Eh? It gets hot, not cold. ;-)
> >

> Nope. Evaporator gets cold...

Which heat exchanger are we talking about? The aux fan runs continually to
keep the condenser cool. The interior fan may be switched off, as
there's a probe in that heat exchanger to prevent iceing.

--
*You never really learn to swear until you learn to drive *

Dave Plowman London SW
To e-mail, change noise into sound.

"Dave Plowman (News)" > wrote
> Malt_Hound > wrote:
>> >>Most cars' blower motor controls are set to run the fan at low speed
>> >>all the time while the AC compressor is engaged. It's done to keep
>> >>air flowing through the evaporator matrix to prevent ice from building
>> >>up on it.
>> >
>> >
>> > Eh? It gets hot, not cold. ;-)
>> >
>
>> Nope. Evaporator gets cold...
>
> Which heat exchanger are we talking about? The aux fan runs continually to
> keep the condenser cool. The interior fan may be switched off, as
> there's a probe in that heat exchanger to prevent iceing.

The AIR passing through the evaporator gets cold, the REFRIGERANT (R12 or
R34)
that is going through the liquid-to-gas phase-change inside it is getting
hot.
Opposite in the condenser.

Floyd

On Mon, 25 Jul 2005 14:58:02 -0700, "fbloogyudsr"
> wrote:

>>> Nope. Evaporator gets cold...
>>
>> Which heat exchanger are we talking about? The aux fan runs continually to
>> keep the condenser cool. The interior fan may be switched off, as
>> there's a probe in that heat exchanger to prevent iceing.
>
>The AIR passing through the evaporator gets cold, the REFRIGERANT (R12 or
>R34)
>that is going through the liquid-to-gas phase-change inside it is getting
>hot.
>Opposite in the condenser.

Yes, in layman's terms a fluid that evaporates sucks in heat; one that
condenses releases heat. It's all made even more efficient and
worthwhile by the latent heat step in the temperature profile of the
transition. But this is getting all too damned scientific.
--
Dan.

Dave Plowman (News) wrote:
> In article >,
> Malt_Hound > wrote:
>
>>>>Most cars' blower motor controls are set to run the fan at low speed
>>>>all the time while the AC compressor is engaged. It's done to keep
>>>>air flowing through the evaporator matrix to prevent ice from building
>>>>up on it.
>>>
>>>
>>>Eh? It gets hot, not cold. ;-)
>>>
>
>
>>Nope. Evaporator gets cold...
>
>
> Which heat exchanger are we talking about? The aux fan runs continually to
> keep the condenser cool. The interior fan may be switched off, as
> there's a probe in that heat exchanger to prevent iceing.
>


I dunno, as I was not the OP. I was just mentioning that evaporators
get cold (and condensers get hot) in the AC scheme.

Fred W