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Posted: Wed Apr 21, 2010 2:20 pm
by spudamine
Did you ever see a fan installed in a refrigerator or a/c unit directed at the body of the compressor?
yes. See the diagram, its from an Embraco service manual. A bog standard compressor just like mine, in a normal refrigerator. This is the third time I've said this, read the manual, forced air cooling is perfectly normal and recommended by the manufacturer.
The point is though that the outer casing gets hot in use, because it is heated by the internal workings, and by blowing air over the casing and cooling it, by definition you are also cooling the internals.
Exactly, the oil sump it's sitting in keeps the internals in better thermal contact with the casing facilitating this.

Posted: Wed Apr 21, 2010 4:08 pm
by boyntonstu
http://www.embraco.com.br/portugue/prod ... EF_ing.pdf
6.1.7 Compressor cooling type

Smaller compressors, with relatively low power motors, can be used in a static cooled arrange-
ment. Compressors with higher power motors require forced ventilation. Some compressors in
the E and T series are also available with an oil cooler. This oil cooler is a coil positioned in the
lower part of the housing immersed in the oil sump. (See “2.7 - COMPRESSOR COOLING
TYPES”).


IOW If the compressor was designed to be fan cooled in an enclosure, it will come with a fan and/or an oil cooler coil.

Have you ever seen (in person) a refrigerator or a/c unit that came with a fan? I have never seen one and I have seen many, many units.

Posted: Wed Apr 21, 2010 4:24 pm
by POLAND_SPUD
lol this gets a bit pointless... damn even if I measure the difference it won't change anything, right ?

Posted: Wed Apr 21, 2010 7:13 pm
by daberno123
boyntonstu wrote:Did you ever see a fan installed in a refrigerator or a/c unit directed at the body of the compressor?
Yes, I ripped a compressor from a dehumidifier which had a fan that blew over the compressor. It was probably well over 20 years old though, so they might not make them that way anymore.

I'd like to see some actual hard data on this subject, so far this argument is going nowhere...

Posted: Wed Apr 21, 2010 7:39 pm
by POLAND_SPUD
yeah as I said I can measure it.... but I already tested it and it is literally
I think that 'ohh it's too hot to touch' when there is no fan....

and

'ohh it's cold' with that bigass fan on
so it's not that this there is any reason to measure stuff... boyntonstu decided to disagree with me in this topic since he feels offended that we have proved he is wrong in his thread 'grains are better than grams'

Posted: Wed Apr 21, 2010 7:51 pm
by boyntonstu
daberno123 wrote:
boyntonstu wrote:Did you ever see a fan installed in a refrigerator or a/c unit directed at the body of the compressor?
Yes, I ripped a compressor from a dehumidifier which had a fan that blew over the compressor. It was probably well over 20 years old though, so they might not make them that way anymore.

I'd like to see some actual hard data on this subject, so far this argument is going nowhere...
I have never seen a dehumidifier without a fan.

I have owned 3 or 4 dehumidifiers.

None of the fans were used to cool the compressor.

The fans blew air over the coils to catch condensation.

Posted: Wed Apr 21, 2010 8:01 pm
by Gun Freak
Oh my god if all you guys keep arguing with boyntonstu then every thread he posts in is going to get locked. :lol:

Posted: Wed Apr 21, 2010 10:58 pm
by MrCrowley
POLAND, If you have ANY way to measure the temp. of your compressor with and without fan, PLEASE do it :D

Personally, I think a fan helps. That's been my experience. Don't have any way to measure the temperature though. Until some tests a done, lets just drop the topic and move on. No point bitching about it anymore :P

Posted: Thu Apr 22, 2010 12:13 am
by spudamine
I'll do some tests as well when my setup is up and running, i'd do it now but I don't have a pressure gauge yet to safely pump up a large chamber and I doubt it will get as hot pumping to atmosphere. Still I have a data-logging multimeter with a thermocouple which should be fairly convincing.
Not sure why I should bother really, kind of like being asked to prove that the earth isn't flat, it really is quite obvious.

Posted: Thu Apr 22, 2010 1:10 am
by Crna Legija
i have one of the old school mercury thermostat.
ill leave it to get to room temp than 15 min w/o fan. let it reset to room temp and try with fan 15 min again

room temp was 23*c 15min without a fan it went to 52*c

i will let it cool down before i test with a fan

Posted: Thu Apr 22, 2010 2:43 am
by jackssmirkingrevenge
MrCrowley wrote:Don't have any way to measure the temperature though.
Er... How do you Kiwis know if you're running a fever?

Posted: Thu Apr 22, 2010 6:55 am
by boyntonstu
-_- wrote:i have one of the old school mercury thermostat.
ill leave it to get to room temp than 15 min w/o fan. let it reset to room temp and try with fan 15 min again

room temp was 23*c 15min without a fan it went to 52*c

i will let it cool down before i test with a fan
125* F is considered warm enough for yeast to rise but not hot enough to kill it.

Why would anyone want to cool a mechanical device down from a cool 52C/125F?

I drink coffee at 155*F.

For comparison:

Dennys 175 degrees
7-11 175 degrees
Jack in the Box 160 degrees
Starbucks 175 degrees

Posted: Thu Apr 22, 2010 7:04 am
by Crna Legija
that was only 15 min i usually run it for 25

could you skull your coffee or do you sipp it

Posted: Thu Apr 22, 2010 7:12 am
by MrCrowley
All the fans I have seemed to found running on commercial fridges are condenser fans, which are sort of useless for us, as this isn't a closed circuit, running cold whatever through the compressor will probably be tricky and/or expensive. I'm beginning to understand what Stu has been saying but I still have seen results using fans on my compressor without fins or coolant.

Posted: Thu Apr 22, 2010 7:27 am
by boyntonstu
-_- wrote:that was only 15 min i usually run it for 25

could you skull your coffee or do you sipp it
http://www.wikihow.com/Drink-Green-Tea- ... de-Effects

Don't drink green tea when it's scalding hot or when it turns cold. The ideal temperature for drinking tea is between 56 to 62 degree Celsius


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