Anyone add a baffle to their fridge?

[73gitane]

My 92 Coachmen's Dometic fridge has marginal performance in hot weather. I'm thinking of adding a baffle to the back of the fridge to funnel air past the condenser. Has anyone had luck doing this in their Class B? It seems like Class B's could really benefit from improved air flow since most have no top roof vents and are compromised by side venting. And there are typically large gaps between the back of the fridge and the sheet metal of the van.

Thanks,
Steve

[markopolo]

I haven't heard of anyone doing that. Maybe work through the diagnostic procedures in the following pdf files first.
If you know the model number of your fridge you can look up the spec and then you can check AC amps, ohms, DC amps etc.

http://gasrefrigeration.net/dom_techdata/36044804.PDF
http://bryantrv.com/docs2/docs/Mandiag.pdf
http://webspace.webring.com/people/jv/v ... Manual.pdf

These are the troubleshooting tips in my Dometic manual:

[stanw909]

Does it have trouble cooling on AC and propane? We need a little more info. If it cools ok on DC but not on propane then you should open everything up and look at the flame it should be blue. Make sure no debris is on the burner and tap the flue a little do get rid of extra soot. If that checks out but flame is not blue then unscrew the jet that shoots the gas into the burner and drop it in alchohol over night ,blow it dry and re instal. It should burn blue after that if not then repeat. The jet has a ruby in it that can get fouled with oil from the propane. Good luck.

[poncho62]

I added a fan to mine to aid circulation of air over the coils too....helps a lot

[booster]

There is supposed to be a baffle that directs the air to the coils. On our Roadtrek, it was attached to the top of the lower vent opening and stuck out about 1.5". I think all the current installation manuals call for one,

Absorption frigs don't do well when it gets hot. Adding a fan to the coils (Snyder kit) usually helps a lot. Many folks can not get their frig under 50* when temps are in the 90's.

[peteco]

I installed a baffle and fan as described in the Dometic manuals. So far the fridge is cooling better. I may install a higher flow fan.

I had tried the Snyder fan, but had some issues as my RT210 fridge has a larger condenser coil and I didn't feel that I had the necessary airflow.

Pete
2006 RT210P

[markopolo]

Dometic vent installation instructions PDF file from 1997 here:
http://bryantrv.com/docs2/docs/dometicventing.pdf

According to it my fridge shouldn't work well ................ but it does.

I don't have a top baffle a.k.a turning vane.
I don't have the bottom baffle.
I don't have a fan.
My clearance "D" is about 5 inches instead of 1".



The guy who built my van and installed the fridge owned a refrigeration company so maybe his years of experience came into play with the installation.

Makes me think other things should always be checked along with ventilation.

1. Venting and installation
2. Thermistor, thermistor adjuster and position of the thermistor on "newer" fridges
3. Thermostat and capillary tube in manual fridges like my 15 year old RM2410
4. Door seal "dollar bill" test
5. AC heating element amp draw meets specification
6. AC heating element ohm test meets specification
7. DC amp draw meets specification
8. Burner, burner orifice, flue baffle annual cleaning
9. Cooling unit

Diagnosing a cooling unit from: http://bryantrv.com/docs2/docs/Mandiag.pdf

After the unit has been operating for approximately one hour, carefully touch the unit at the boiler box and the absorber area. These areas should be approximately the same temperature, regardless of the ambient temperature. Equal heat between the boiler and the absorber indicates the fluid circulation within the unit is good.

One of the faults with a cooling unit is a blockage. This can happen when the unit is operated off-level, or if too much heat has been applied to the boiler area. To the touch, this unit will be extremely hot at the boiler with little warmth at the absorber. In other words, no circulation.

I wonder how well my fridge would work in really hot temperatures down south? I could see one or two fans mounted to the upper exhaust vent helping in that situation.

Capillary tube:
http://www.rvmobile.com/tech/trouble/2801Sys.htm
http://rvmobile.com/wb/default.asp?acti ... 2988&fid=2

[73gitane]

Wow, lots of great information to digest! I'll look it all over closely and follow up. It's a RM2410 and performs pretty much the same on electric or propane.

The van was new to me last November and had had the cooling unit replaced by the dealer. By the time summer arrived I began to be unimpressed with the cooling. I then contacted the rebuilder and to their credit they agreed to replace the cooling unit. The replacement unit worked exceptionally well but failed after about 36 hours. The fridge was only tested outside of the van in the garage so I didn't have any real world experience with it. The rebuilder then sent another unit and while it was better than the first one it didn't perform as well as the second one. At this point I relented and figured this is as good as it gets.

When I tested it today the best delta in temperature I recorded was 53 degrees. This was at noon and the interior of the van was 85 so the fridge was at 32. Outside temp was about 70 with clear sky and sun beating down on the side vents. Later in the afternoon the fridge temp went to 43 while interior of van shot up to 90. Outside temp was a pleasant 75.

I think I might try a big box fan at the upper vent just to test if better ventilation will make a difference.

[markopolo]

Another Dometic fridge service tips manual:
http://gasrefrigeration.net/dom_techdata/2552.pdf
From 1996 and covers model numbers:
RM2310
RM2410
RM2510
RM2610
RM2452
RM2453
RM2552
RM2553
RM2810

Looks to be good manual to have. Very comprehensive.

[Ron J. Moore]

Thanks Marko, good info that could be often overlooked. Safe travels. Ron

[73gitane]

Well I added a couple baffles and the difference was nominal. I got better results by adding a fan to the cooling fins at the back of the fridge. There's about three inches of space on each side of the fridge so I might add insulation. I do appreciate all the good advice.