Dometic refrigerator refrigerator will not cool on electricity or gas. Could the system need to be recharged?

Fist off before you get crazy replacing things make sure the camper is level when testing this. Gas will not run to it if you are not level. Also make sure the gas is turned on and make sure you have selected automatic or gas only on your fridge. Also give it about an hour before you test the temp. These take a bit longer to start feeling cool. If all of that does not work you will need to check the refrigerant, igniter(for the gas side) and the compressor. Also make sure the fuses are good to go at the main panel and that the breakers are in the "on" position

check the flame if it reaching the tube

When operating on Electric, if the rear of the cooling coils get warm and the fridge is level, but the refrigerator does not get cold then it is more then likely your cooling unit that has failed. Visit ArctiCold Refrigeration We keep it cold for info on replacement cooling units.... I have also attached a video with tips on diagnosing the RV fridge,
Arcticold New replacement cooling units can be purchased from Ebay Dometic RM760 Brand New Manufactured Cooling Units LIFETIME WARRANTY

my domestic refrg will not work on electric but will lite on gas. freezer will get cold on gas but bottom will not cool.you can plug refrg in and it will kick the gas off. you unplug refrg on gas will lite.that part of the power board seems to be working.

If by 'gas' you mean refrigerant, then yes, it can be recharged. However, in order to legally recharge a refrigeration unit with refrigerant you need a special certification from the EPA. I recommend you get a certified technician to take a look at your refrigerator

Do you mean it runs OK on gas ?
If so you probably need an element.
If not , you need a new sealed system

It could be as simple as a blown fuse at the fridge. Also check to make sure you have turned on the electric switch that allows the fridge to run on AC. Note, you can only operate the fridge on EITHER gas OR electric, but not both sources at the same time, thus, you have to turn off the gas switch before you can run on electric.

When this unit is running on electricity, it has to have the thermostat set for it to run.

Here's a link to the Dometic manual for your model.

http://www.alcovr.com/DATA/MANUEL/DometicRefrigeratorModelsRM2191&RM2193.pdf

Just follow the steps for running on electric and you should be OK.
Hope this helps.