Date: Thu, 24 Jul 2008 20:15:13 -0700
Reply-To: Alistair Bell <albell@SHAW.CA>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Alistair Bell <albell@SHAW.CA>
Subject: Re: Your Dometic's Best Temp Differential On LP?
In-Reply-To: <c4e7c5f90807240959n30344e4bm47d2107e3cf3abad@mail.gmail.com>
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My post, last year:
From: albell@uvic.ca
Subject: Re: Dometic in 100F ambient?
Date: August 16, 2007 5:38:25 PM PDT (CA)
To: vanagon@GERRY.VANAGON.COM
Reply-To: albell@uvic.ca
Ah the dometic threads, such a sign of summer :)
Its not coincidental that I have been thinking about the Dometic a
lot recently, what with brainstorming with fellow list member P.
Chubbuck and adding some stuff to the vanagonwiki. I have, and many
other's too, posted temp data and modifications to the stock fridge
( i understand that record of the list's emails are collected and
organised in some sort of "Archive"), and in the last 2 days I have
tried couple more things.
1. I replaced my little muffin fan on "icebox" grill with a littler
and quieter one (intel branded CPU cooler). the interior fan is good
mod. I recorded some fridge temps after the mod, remember this is
Victoria BC , not Tuscaloosa, so ambient temps are more civilised. I
kept the van closed tight, new interior fan on, fridge empty.
time fridge temp van temp elapsed time notes
18:00 27.4 25.7 0
18:10 28.1 26.8 10
18:15 25.7 27.1 15
18:20 23.5 27.4 20 back fan on
18:30 19.7 27.4 30 back fan on
18:55 12.1 28.2 55 back fan on
19:05 9.9 28.1 65 back
fan on
19:11 9.0 28.1 71 back
fan on
19:32 6.6 27.8 92 back
fan on
19:44 5.6 27.6 104 back
fan on
19:57 4.8 27.4 117 back
fan on
20:10 4.1 26.9 130 back
fan on
20:23 3.6 26.5 143 back
fan on
21:05 2.2 24.8 187 back
fan on
not bad performance. the back fan is a muffin fan i used to replace
the stock fan. I have to admit it is not as efficient as the stock
fan, it stay on more, doesn't cycle as much.
My set up as of yesterday also had a muffin fan (switched) attached
to grill on left side of stove unit, right adjacent to the stowage
bins. You can feel the waste heat from the fridge come out there. I
(and I think others) thought a fan there would help cool the back
coils of the fridge. I think it does but, in the summer, that hot air
now blowing rather than convecting is not cool :)
this afternoon i had the chance to pull the fridge out of the van to
give it a once over. I had left the fridge running after my temp
recording expt and found next morning the flame had gone out. I
wondered if the by-pass jet in the thermostat control had plugged or
maybe it was a combustion chamber problem. Turned out I was out of gas.
But i pulled the fridge. The by pass jet was clean. The combustion
chamber was dirty. fine metallic dust, which looks like it was coming
from the inlet and exh. pipes. I blew the pipes out with compressed
air, blew the main jet, sealed the cracked grommets where the
thermoprobe and piezo connect. I also removed the side grill fan and
did the mod to the city water access port, adding a switched muffin
fan. So instead of a fan just pushing hot air faster into the cabin,
i have a fan pushing the hot air out of "flapped" city water port.
That port mod looks like a winner, hats off to the list-members that
invented it.
Alistair
On 24-Jul-08, at 9:59 AM, neil N wrote:
Hi all.
Couldn't find a thread about best temp differentials on LP mode in
archives, so here I am.
This is for a Dometic 182B with a small CPU fan inside.
Last night, 10 PM, ~66F inside Westy. Run overnight on LP at "Max",
9AM ambient: 66F. Fridge: 27F. Roughly a 40F differential.
IIRC, my old 182A pulled better temperature differences. It made ice
with ambient temps of 70F-8?F.
(I swapped it out as flame went out when turned down at night.
Relighting the next morning was a major PITA.)
I know 40F differential is typical, but if others are seeing better
results, then I'll be cleaning the LP jet. (yes I should have done
this before. It worked on the bench so I let it be --- :^)
Thanks,
Neil.
--
Neil Nicholson '81 JettaWesty "Jaco
http://groups.google.com/group/vanagons-with-vw-inline-4-cylinder-gas-
engines
http://web.mac.com/tubaneil
http://tubaneil.googlepages.com/