Dometic Refer Not Staying Cold

[MDPD]

We have a relatively new to us 2009 Tour with a Dometic NDA 1402 refrigerator installed in the slideout. On the highest setting, the refrig temp will be between 37 and 40 when we wake up. During the course of the day when the ambient temp climbs to 90-94 the temp inside will go up as high as 49 and then back down at night. I have run it on electric and gas with the same results.

I tried calling Dometic but they are no help and only refered me to a service center. In reading some of the articles there was mention of the out side coil cooling fan not working would cause this issue. I have looked and listened but can not find a fan to help exhaust the heat from the rear of the unit. Is there supposed to be a fan installed? and if so where is it? Will adding a computer fan help with this problem.

All help will be greatly appreciated.

 

[Gocoffeer]

Heat removal and air flow at the top of the refrig is paramount to good cooling for this type of non pumped ammonia unit. From the brief description you are offering....it sound to me like the refrig is not properly able to vent out the heat during the hot days. I am assuming that in the evening thru early day it begins to chill down again.
This condition can be altered by manipulating the refrig roof vent. There are forced air vent covers for these units and they work.

Camco - Solar Powered RV Fridge Vent Kit (Includes Panel & Fan) - Item #42162 on eBay!

 

[Libero]

We have a relatively new to us 2009 Tour with a Dometic NDA 1402 refrigerator installed in the slideout. On the highest setting, the refrig temp will be between 37 and 40 when we wake up. During the course of the day when the ambient temp climbs to 90-94 the temp inside will go up as high as 49 and then back down at night. I have run it on electric and gas with the same results.

I tried calling Dometic but they are no help and only refered me to a service center. In reading some of the articles there was mention of the out side coil cooling fan not working would cause this issue. I have looked and listened but can not find a fan to help exhaust the heat from the rear of the unit. Is there supposed to be a fan installed? and if so where is it? Will adding a computer fan help with this problem.

All help will be greatly appreciated.

Not familiar with your fridge, but my Dometic RM7561UL did not come with a cooling fan.

Lowering ambient Temp around the rear mounted cooling fins will lower the inside temp as witnessed by the temp change you mentioned. I installed two computer fans to extract hot air from my cooling fins at the rear of the fridge. I did not do precise temperature measurements inside the fridge yet with the fans turned on and off yet but it appears to be working OK at ambient temps around 82F. If you do not have an operating fan, I suggest you try putting a regular clamp on fan to cool the fins and see what difference it makes in your situation under the temperatures you are experiencing.

Computer cooling fans do move a lot of air and with the correct positioning they should work for you and draw very little power. I think mine draw about 250ma each.

Good luck.

 

[Dave78Chieftain]

A google search indicates having a Dometic NDA1402 installed in a slideout can be problematic. Parts book (http://67.238.126.140/pdf/3309892.002.pdf) indicates there are fans inside but not outside.

http://www.irv2.com/forums/f103/updated-fix-dometic-sidewise-nda1402-owners-49058.html

Tech- Inside a Dometic NDA1402

Dave

 

[JC2-WO]

Heat removal and air flow at the top of the refrig is paramount to good cooling for this type of non pumped ammonia unit. From the brief description you are offering....it sound to me like the refrig is not properly able to vent out the heat during the hot days. I am assuming that in the evening thru early day it begins to chill down again.
This condition can be altered by manipulating the refrig roof vent. There are forced air vent covers for these units and they work.

Camco - Solar Powered RV Fridge Vent Kit (Includes Panel & Fan) - Item #42162 on eBay!

I seriously question the quality/efficiency of these solar units from what others on the web have mentioned. A properly vented fridge with adequate fans on top of the fridge will work wonders. If you don't have at least (2), add them. We control ours with a toggle switch instead of the thermal disc used by others. They seem prone to fail at the most inconvenient times. Our switch is located in a top cabinet next to the fridge.

 

[MDPD]

After reading your replys, I spent the afternoon trying to figure out where to put fans and came to the conclusion that the only place available to mount them without removing the frig was just inside the upper vent pulling the hot air out. This decision was made after removing the upper vent and feeling the heat that was trapped above the vent escape. I am going to order two 64 cfm fans and mount them to the sheet metal deflector that blocks half of the vent cover aimed out toward the vent openings and switch them from inside. I am not an engineer, but I really do not know what they were thinking when they designed this installation.

As with all the advice I have received from you all over the years, if anyone has a better idea I would appreciate hearing.

 

[garykk]

Just a thought......on one of the cooling fins in the refer there is a small clip that is used to control the temp, can't recall what it is called but it can be adjusted. Perhaps it was accidently moved?

 

[Jerry J-ClassB]

Thermister?

 

[ruffian]

Has anyone done any testing on how much reefer cooling ability is effected by the level of the box?

Three degrees they say, is ok, but is it cooling as well as it would if it was only 1 degree off level.

My Amish unit seems to work better when very level but have no way to come up with a definitive answer. To may variables to be sure.

For now I will put a little more effort into leveling the reefer.

 

[Five2o]

I have a 2010 Ellipse with that fridge and had similar problems.

I did get a board replaced on warrenty when 1st problems appeared but fridge was still useless so I took matters into my own hands.

There are 2 fans controlled by a thermostat switch attached on the exterior top access panel. The .fans are not accessible, but I remove the thermostat and hardwired the fans to a switch I turn on if its warm out.

Also unscrew the thermistor in the fridge compartment and leave free of the cooling fin. Experiment with this...I ended up isolating the thermistor from the cooling fin with a chunk of duct tape then re installed the screw.

My fridge keeps beer at 35 degrees using 120v ac or on propane in 90 degree heat for the last year or so. Hope it works for you.