07-23-2014, 02:30 PM
|
#1 (permalink)
|
|
Not bad for a machine
Join Date: Mar 2014
Location: Baltimore
Posts: 1,024
Thanks: 279
Thanked 242 Times in 179 Posts
|
Electric fan when the engine is off or on?
What is more efficient? What is better at cooling? What uses more electric? When should I use my electric fan?
I have it hooked up to a switch on the dash so I can turn it on and off when needed. Just thinking when the best time to use it is.
Does it not make a difference? Hmmm...
__________________
|
|
|
|
 Today
|
|
|
|
Other popular topics in this forum...
|
|
|
|
|
07-23-2014, 02:45 PM
|
#2 (permalink)
|
|
It's all about Diesel
Join Date: Oct 2012
Location: Porto Alegre, Rio Grande do Sul, Brazil
Posts: 12,864
Thanks: 0
Thanked 1,683 Times in 1,501 Posts
|
It's not unusual for electric fans to remain running for a while after the engine is shut off, but it might be not necessary at all since the engine won't be generating more heat when it's off.
|
|
|
|
|
07-23-2014, 02:46 PM
|
#3 (permalink)
|
|
Not bad for a machine
Join Date: Mar 2014
Location: Baltimore
Posts: 1,024
Thanks: 279
Thanked 242 Times in 179 Posts
|
Sorry I was talking about during EOC.
__________________
|
|
|
|
|
07-23-2014, 02:50 PM
|
#4 (permalink)
|
|
It's all about Diesel
Join Date: Oct 2012
Location: Porto Alegre, Rio Grande do Sul, Brazil
Posts: 12,864
Thanks: 0
Thanked 1,683 Times in 1,501 Posts
|
Quote:
Originally Posted by dirtydave
Sorry I was talking about during EOC.
|
If the engine is off, I guess it's better to keep the fan off too anyway. Since you'd be coasting, could rely on the air flow  |
|
|
|
|
07-23-2014, 03:16 PM
|
#5 (permalink)
|
|
Not bad for a machine
Join Date: Mar 2014
Location: Baltimore
Posts: 1,024
Thanks: 279
Thanked 242 Times in 179 Posts
|
Quote:
Originally Posted by cRiPpLe_rOoStEr
If the engine is off, I guess it's better to keep the fan off too anyway. Since you'd be coasting, could rely on the air flow |
Or have the fan on for extreme cooling?!
No extra load when the engine is running...
__________________
|
|
|
|
|
07-23-2014, 06:09 PM
|
#6 (permalink)
|
|
Just cruisin’ along
Join Date: Jul 2009
Location: Rochester, NY
Posts: 1,183
Thanks: 66
Thanked 200 Times in 170 Posts
|
I'd also say off while coasting. You get plenty of cooling while gliding and once you restart that cool water gets pumped back into the engine.
__________________
'97 Honda Civic DX Coupe 5MT - dead 2/23
'00 Echo - dead 2/17
'14 Chrysler Town + Country - My DD, for now
'67 Mustang Convertible - gone 1/17
|
|
|
|
|
07-23-2014, 07:55 PM
|
#7 (permalink)
|
|
It's all about Diesel
Join Date: Oct 2012
Location: Porto Alegre, Rio Grande do Sul, Brazil
Posts: 12,864
Thanks: 0
Thanked 1,683 Times in 1,501 Posts
|
Quote:
Originally Posted by dirtydave
Or have the fan on for extreme cooling?!
No extra load when the engine is running...
|
Under a low load it would probably not worth the "extreme" cooling, since it would still impose a little load on the electrical system. |
|
|
|
|
07-23-2014, 08:15 PM
|
#8 (permalink)
|
|
Cyborg ECU
Join Date: Mar 2011
Location: Coastal Southern California
Posts: 6,299
Thanks: 2,373
Thanked 2,172 Times in 1,469 Posts
|
An electric fan runs off the battery, not directly from the engine. So its load is rarely or never borne directly by the engine at the moment of the fan's use. At least it is not easily predictable when the electric load will bring on the alternator to charge the battery. Run it during EOC or during engine-on pulses and I am not sure it will make a difference.
__________________
See my car's mod & maintenance thread and my electric bicycle's thread for ongoing projects. I will rebuild Black and Green over decades as parts die, until it becomes a different car of roughly the same shape and color. My minimum fuel economy goal is 55 mpg while averaging posted speed limits. I generally top 60 mpg. See also my Honda manual transmission specs thread.
|
|
|
|
|
The Following User Says Thank You to California98Civic For This Useful Post:
|
|
|
07-23-2014, 09:03 PM
|
#9 (permalink)
|
|
Human Environmentalist
Join Date: Aug 2010
Location: Oregon
Posts: 12,741
Thanks: 4,316
Thanked 4,468 Times in 3,433 Posts
|
Running the fan with the engine off (alternator off) is the least efficient way to run. The lead acid battery is extremely inefficient at charge/discharge, so running the fan from the alternator output is better.
Regardless, the fan should not be manually controlled. It needs to come on when the engine is too hot, and switch off when temperatures are ideal. The driver should not be distracted with trying to control temperature when the thermostat does an excellent job of this already.
|
|
|
|
|
The Following User Says Thank You to redpoint5 For This Useful Post:
|
|
|
07-24-2014, 02:29 PM
|
#10 (permalink)
|
|
It's all about Diesel
Join Date: Oct 2012
Location: Porto Alegre, Rio Grande do Sul, Brazil
Posts: 12,864
Thanks: 0
Thanked 1,683 Times in 1,501 Posts
|
IIRC he was considering an alternator delete.
|
|
|
|
|
