Dometic 3n1 absorbtion- what's realistic ?

PSW wrote:


I always tried to park the RT so that the sun hit the side with the refrig the least amount of the time....sunnyside on the other side than the refrig.

This is the only way my fridge will seem to cool properly. I was going to post this. A very important step. Shade is key.

Yes the seal is pretty good- did the dollar bill test all around the edges.

and do have a remote thermometer sender inside the fridge so we can see how it's doing.

thanks, Mike

When we had our 2007 Roadtrek with the dometic, we ran it like you do: dc going down the road and AC if we had hookups (seldom)and propane the rest of the time, most of the time since we boondock for days at a time. We had no problems when the temps were 100+ and the temps stayed at mid 40s in the heat of the day, cooling down with the day.

I always tried to park the RT so that the sun hit the side with the refrig the least amount of the time....sunnyside on the other side than the refrig.

Also, I think a ten buck wireless indoor outdoor thermometer is a necessity. Put the outdoor sender in the center of the fridge and monitor the temps from somewhere else in the coach. My wife is a fanatic about keeping the proper temps. We had that rig seven years and had no problems keeping it cool in hot weather. She kept the indoor/receiver unit velcrowed to the dash in front of the passenger seat so she could monitor going down the road as well as when parked.

No doubt about it: DC is really good only to keep what is cold cold and you better be running the engine or your coach batteries will drain pronto.

Is the seal around your door in good shape? Is the material still flexible and "alive"?

Paul

I have a small camco 2xD cell fan inside- it is a gentle waft..and does help

I have no 12 volt inside the fridge, one of the things I will look at is running 12 VDC inside for a fan and light

the gap between the coils and outer wall is about 3/4"- even with no fans there is good convection in the bottom, out the top.


Propane; one of the things I will look at is jetting we live at 1400' but much of our camping is 5000'~8000'
I'll save that until I have charted some baselines

mike

Do you have a circulating fan of some type inside? When loaded with stuff you will not get much natural convection past the cooling fins inside, and even a small circulating fan will improve things. I have a computer fan wired into the hot side of the light switch so it runs as long as the fridge is on. It helps cool down faster and returning to cool after opening, it uses very little power and is one of the best mods I have done. Even in summer temps here in the SoCal desert it will maintain in the safe zone for food on propane, which puts out more btu than the electric heater thus more effective.

Check and be sure the fridge is properly baffled by looking up from the outside panel. There should be only around an inch of space between the coils and the wall to create the chimney effect. If not, you will need to fill it somehow.

well the past few days have shown that on AC the fridge will stay 55º or so below ambient.

when it is 110º that's not cold enough. but it is when 90º

( so even if at a campground with AC power and airconditioning on- we may see better fridge temps as the van will be cooler, less heat soak on the fridge)

when powering up, drop in temps of about 6º each hour until we cannot cool any father.


this morning at 10am it was 100º and fridge was at 40º....switched to propane and no huge advantage so far over the ac.( the past 5 hours)
I'll watch this for a couple of days.

In propane mode I am starting at single fan with heat switch ( as when we bought it)


then will try with my 4 fan package.

possible too much air flow could affect the propane heating, we'll see before/after


Mike

mkguitar wrote:

If you can suggest a different way to test I'd be interested in your experience

Try it a time or two with skipping the DC part. That likely is the most inefficient mode, followed closely by AC.

I just leave mine on propane all the time. Cools good, doesn't use much gas and a tiny bit of battery.

I would use AC only after getting it good and cold.....where shore power is available. It takes mine a good 8-10 hours to get noticeably cold when on AC. Only a couple of hours on propane.

All of your messing around with fans probably isn't really helping much and might be counter-productive. Are these fans being used inside the fridge or outside ?? 100CFM is WAY overkill for inside......and probably mild overkill for the external part too.
More is not always better.

mkguitar wrote:

On our recent trip we were generally on AC at night, DC while driving and propane while parked during the day

- sorry if there is an image added to your post, I cannot see it.

AC power at a campground...DC while driving and propane when parked for any length of time ( better cooling/save batteries).

2.) fridge temps will be dependent on ambient temps.being in the Southwest our avg ambient temps through a 24 hour period may be 30 or 40 degrees higher than Maine or Midwest.
Being in PHX, I'd guess we are 10 or 15º higher than yours in Verde Valley

If you can suggest a different way to test I'd be interested in your experience

Mike

Just curious why the swapping between different modes...........testing :H
AC at night, DC while driving, Gas during day while parked.

DC is the 'worst' method for cooling.....

IF you are maintaining freezer at 0*F to -5*F and food section at 38*F to 42*F fridge is doing as well as any absorption fridge.
(Temps measured using thermometer in glass of water)