Adding a fridge-fan (12V/110V) to the Dometic 182 whitout removing the fridge (click on a picture for a bigger view)
First lets see why: All fridge have a fan, simply because it help getting the cool air circulating everywhere, especially to the bottom part of this one.

What we need for a 12V and 110V operation: Click here to see the possible wiring diagrams

The fan (C):

You can spend hours finding the right fan, I did. Here is what you are looking for in a fan:
  • Size (no more than 2 3/8 in): The fridge is small so no need for a bigger fan. A smaller one doesn’t have enough air flow for all that trouble.
  • Current consumption: Stay bellow .30amp (300mah), yes I know, even a 750mah would last for a day or 2 before draining the battery but why have more. No need.
  • The airflow or RPM: get a 3000 to 4000 RPM computer CPU fan. They have the best rpm/airflow/noise rate. The 9000 to 11000 are too noisy, the flow of those one is too strong for nothing.
  • Noise: another good reason to stay with a 3000 to 4000RPM and .300mah. Most CPU fan are brushless fan and have ball bearing. They will last forever (at least a few years) and cost nothing (4.95CAD-2.75USD) at any electronic part store (don’t go to a computer store, they will rip you right away.
Fan cover (E): A must, so your stuff and fingers won’t get into the impeller and break this one.(.99$)

A switch (D): If you don’t want to use the fan in 110V mode, simply buy a 2 position (ON/OFF) normal micro switch. If you want to have a fan running on 110V you will need to buy a ON-OFF-ON switch that hold the ON position, not a (ON)-OFF-(ON). Chose a good quality switch with 6 connectors (see diagram).

A small power bar(B): You will need this one if you use a 110VAC/12DC transformer / converter. This will be hooked to the fridge existing location under the sink.

A 110VAC/12DC small transformer / converter(A): This will have your fan working on 110V. Very cheap to buy at any electronic parts dealer. Get at least 200mah more than the fan consumption. I use a rechargeable wireless phone adaptor (110VAC / 12VDC 400mah). 

Click on the picture above for a big size view.

White shrink (F): To get that black fan wire in the fridge a nice look.

Small parts: Tie rap, solder, electric tape and so on.

Find a suitable fan location. I chose to put mine upward close to the cooling element, my first Idea was to put this one flat on the grill so she would push air below but she was making to much noise due to resonance/oscillation. The upright position gave me the lowest noise and I like the idea that the fan takes cool air from the back and send it forward.

First, get the fridge door, the fridge front plate/panel (3-right screws) and the drawer out. Next, remove the upper fridge grill and fix the fan with tie-rap to this one (see picture). Add a wire extension to the fan and put the white shrink on it (about 2 feet). You will have to drill (1/4) a small hole on the upper front part of the fridge door (When remove, see picture). When done, replace the fridge front panel and the door.

Remove the font metal panel with the name “Westfalia” and the 12-volts fridge control panel. 3-screws bellow and 2 screws on each side. Unplug the 12-volts fridge control panel, and remove the control panel from the front metal part (2-screws). You will have to choose a location for the switch, drill an appropriate hole for this one. Disassemble the fridge control panel for later wiring.

the fridge AC connection below the sink and add the power-bar on the upper wall behind the drawer, plug the fridge and the new 110V adaptor to this one. The upper adaptor (yellow arrow) is for my portable vacuum cleaner. Red arrow is the new fan 110V adaptor and the grey wire (pink arrow) is the fridge wire. Pass the new adaptor wire on the left side of the sink between the 2 shelf. (see picture below)

First take a look at the wiring diagram so you can choose which kind of layout you will choose (picture on the right). Take your 12VDC van source from the fridge control panel, follow the big red and black wire from the big connector (see picture) that plug into the control panel. (I don’t remember which color). You are now ready to begin your wiring. The 110V/12V come from the adaptor; the 12VDC car voltage comes from the fridge control panel (or elsewhere, your choice!).
  • Yellow arrow: 110V/12VDC from the adaptor
  • Red arrow: 12V source from the fridge control panel.
  • Green arrow: To the fan

Note: on the picture the wiring was not finish. You can also see the location of the 110V/12V wire left of the sink. On the left side you can see the big plug that attach to the fridge control panel.

Note: You can also add a warning 12V light (just to tell you that the fan is working) in parallel with the fan; you just have to drill another hole beside the switch.

Final view (clean job):