|
|
|
|
|||||
|
||||||
(no email)
Date: Sat Jul 29 2006 - 03:54:32 EDT
When I got my trawler, it had an old Norcold with two separate 12v
compressors. In cool weather, it did the job and would have been
sufficient had my boating waters been the NE or NW. However, I live in
FL, and that means that for 9 months of the year, I can count on having
temps in the upper 80's to mid 90's. When it got that warm, the Norcold
never shut off and continued to have tremendous ice buildup, so I
scrapped it.
I replaced it with a straight, appartment sized, 11.5 cu ft Ewave
refrigerator. At the time I was shopping for this refrigerator, I was
focused on energy ratings and reading the little yellow EPA required
tag that is inside all refrigerators sold. I now realize, having used
this refrigerator continously for 3 months, that purchasing a
refrigerator based on its efficiency rating was wrong, and this is why.
The compressor and heat exchanger coil for this refrigerator are
totally located at the bottom of the box, inside a CLOSED COMPARTMENT.
This does not allow enough surface convection for a boat. Wish I had
just followed Phil Rosch's example, and bought a Kenmore or any other
brand, with the cooling coils going up the entire rear outside of the
box, but at that time, it didn't dawn on me that where the coil was
located was critical to the running time for a fridge that was going to
be in a closed, but ventilated, compartment on the boat.
I thought the unit with the closed coil would have more protection from
damage when putting it aboard, as opposed to the external coils, which
in most cases are attached pretty flimsily to their boxes. Net result,
in warm weather my unit is running about 90% of the time instead of the
50 to 60% that I would like it to.
The discussion on TTL finally motivated me to do something about this
after thinking about it for 6 months. Yesterday, I ordered a
ThermalTake Smart 90mm muffin fan from Tiger Direct. It was $10.99, and
I ordered another ordinary fan, if I need it, for $4.99, and yes, both
have roller, not sleeve, bearings.
Tiger Direct has about 60 (!) different computer fans in stock. The
specs for the fan I chose were: it is a variable speed that you can
set. It moves from 24.6CFM to 78.7CFM based on the speed setting. It
has a built-in thermostat, so I don't have to go out and buy a separate
attic one. Current consumption is 0.15A at the lowest speed; and 0.48A
at the highest speed. The second Mascool 90mm fan moves 45.18CFM
continuously, while consuming 0.18A.
Either or both fans should work well simply because the air that will
be drawn over the coils will be concentrated in a small area.
Questions for the present discussion: How many CFM should the people
with the Norcolds, or any other brand whether 12v or 110v, try to move
and for what desired current draw? Obviously, the more air you can
move, using the least amount of current is desireable, but what minimum
air volume do you need to reduce run time significantly?
This also relates to another thread going on whose subject is Engine
Room Temps. Everything I've read in the posts has been subjective, with
the exception of the goal of keeping the engine room no more than 30 d.
above ambient temp. I have a temp problem, again, because I boat in FL.
I want to add a squirrel cage fan. How many CFM should it be?
Hope I can get some answers from the people that have already added
cooling fans to both fridges and ER's.
Martin Veiner
Unlimited Internet Access with 1GB of Email Storage.
Visit http://www.juno.com/value to sign up today!
_______________________________________________
http://lists.samurai.com/mailman/listinfo/trawlers-and-trawlering
To unsubscribe send email to
with the word
UNSUBSCRIBE and nothing else in the subject or body of the message.
Trawlers & Trawlering and T&T are trademarks of Water World
Productions. Unauthorized use is prohibited.
|