Refrigerator Vent Improvement

With the compact design of the Aliner, there is little room for adequate cooling of the refrigerator.  Another owner improved his camper by adding a clothes-dryer vent outlet behind the fridge, significantly improving the cooling air flow.  I copied his idea, with a few adaptations.

Step 1: Removing the countertop.  I decided that removing the countertop would make the job much easier, and it proved to be the right approach.  The top was secured by 4 "L" brackets.  The 2 rear brackets were easy to remove since they were accessible from the upper vent.  Then I raised the rear of the counter, slid a 1x2 crosswise underneath, and pulled it as far forward as possible.  A couple of good bangs on the rear of the counter popped the front brackets loose.

Step 2: Installing an outlet.   This proved to be a good time to add a much-needed outlet to the dinette side of the cabinet.  There was just enough room to mount it horizontally between the framing pieces above and to the left of the fridge.  The outlet is wired to the cut-off female end of an extension cord.  There was not enough room to mount a protective box around the back of the outlet, but electrical tape (red in the photo) protects the bare wires.  The male end of the cord connects to a multiple plug at the fridge outlet in the bottom rear of the cabinet.  I had thought of replacing that single outlet with a standard double outlet, but decided it was not worth the trouble. Now we have a convenient power source at the dinette for a lamp, radio, or other small appliance.

Step 3: Inserting the dryer vent.  This was the most difficult and daunting part of the whole process.  I purchased a plastic dryer vent outlet from Lowe's.  First, I hot-glued insect screen to the inside of the removable vent grid and hot-glued the grid back to the vent.  Then I had to cut off the "collar" on the back side of the vent - carefully and slowly with a combination of razor knife and utility shears.  It isn't the neatest job in the world, but it doesn't show. 

The next part was worse.  The dryer vent "hood" widened from top to bottom.  I made a paper pattern of the shape of that hood and traced it in pencil on the middle front of the camper upper vent door, matching the top of the cutout to the bottom of the door border.  I used a keyhole saw (an inexpensive and useful hand tool) to cut that hole in the door.  When I pushed the vent hood through the hole from the rear, the back part fit fine.  What I hadn't calculated was that the vent hood also tapered from side to side, leaving significant gaps (as much as 1/4") between the hood and the cut edges in front.  Oh, dear!  Poking through odds and ends in the garage, I found a piece of white plastic 1" L molding, intended to hold suspended ceiling tiles against a wall.  Carefully trimmed, bits of that molding did a nice job of finishing the front sides of the hood.  At the top of the hood, I used another piece of that trim to fill in the gap left between the sloping hood and the vent-door border.  I also cut a small piece of white plastic (from a gutter cover) to cover the bottom center projection in my cutout, blocking that opening from water or exhausted hot air

I secured everything with hot glue, and caulked any gaps where rain might run in.  Lastly, I hot-glued insect screen over the back of the door, except for the circular vent hole.  I hope I never have to make another modified vent door like this - it worked, but it was a real pain!

NOTE:  There are many white plastic/vinyl products, like gutter cover, strips of siding, suspended-ceiling hardware, etc. that can be adapted for DIY projects.  It can be fun to prowl hardware store aisles to see what you can discover.

Step 4: Repositioning the exhaust fan.  This part was relatively easy, except for the tight space.  From the outside, I removed the screws holding the fan brackets to the cabinet frame, then removed the screws holding the brackets to the fan.  There was plenty of extra wire wrapped around the fan case, so a quarter turn of the whole thing gave enough slack to move the fan forward to the center of the vent.  To match the fan to the opening in the vent door, I lowered it, using L brackets to fasten it to the cabinet frame.  In the picture below, you can see the brackets shimmed with scraps of wood to give the proper drop.  After I bolted the Ls to the fan brackets, I remounted the brackets on the fan; the large hole had to be on the outside with the head of the screw so that the screw points fit between the cooling fins.  There was no room for nuts, and the screws were a bit loose.  I solved the problem with a couple of "quick nuts" - flat bits of metal.  Now that the fan is mounted more securely than before, there is less vibration and less noise.

In the process of pushing the fan behind the fins, I put extra pressure on the frame of the vent door and popped the caulk.  It turned out that the vent frame was secured to the camper body only on the sides, so I added L brackets to the the top, using the existing screw holes in the door and large nuts as spacers below the wood frame.  It's much more solid now.

Step 5: Baffles. To improve air flow and cooling, I was advised that it was important to keep hot air from accumulating in "dead spaces" above and behind the fridge. 

TOP Baffle: With the countertop removed, I cut a piece of Reflectix to fit on top of the cooling fins, notching it around the magnetic countertop catches and tucking the inner edge down behind the fins.  I then laid insulation against it to keep escaping hot air from accumulating in the dead space underneath the countertop.  The countertop holds everything in place. 

BOTTOM Baffle:  I needed to force the cool air, coming in from the bottom vent, to rise through the hot coils and fins instead of uselessly against the outer wall.  The hardest part was figuring out what materials to use to make the bottom baffle.  At Lowe's, I bought a strip of white vinyl siding (left photo below) and a 2' length of 4" aluminum snap-lock pipe, found in the duct section of the store (second photo from left).  I cut the vinyl to fit horizontally inside the bottom of the upper vent door between the outer wall and the fridge gas stack, leaving the lip on one long edge.  The flat edge slips between the wood and the vent-door frame,  and the the lip is toward the stack, pointing up.  Holding the open aluminum pipe sideways, with the crimped edge at the top, I cut off the sides and bottom edge (use gloves - the cut edges are deadly!), ending up with a piece that would slip down behind the vinyl and reach the top of the bottom vent-door opening.   The crimped aluminum edge catches on the vinyl lip and both are secured with long sheet-metal screws to existing holes in the door frame (third photo below).  The sharp aluminum corners are protected with duct tape.  The vinyl piece on top not only looks good, it keeps dust, dirt, or road spray out of the insulation. 

From the bottom door opening, I shoved insulation up between the bottom baffle and the outer wall.  When the space was full, I used sheet metal screws to secure the bottom of the aluminum piece to existing holes in the top of the bottom vent-door frame (right photo below).  The bottom baffle now blocks the dead air space against the outer wall and the back of the fridge is cooled much more efficiently.  After a 5,000 mile camping season, I can declare the baffles a success!

Step 6:  Remounting the countertop.  Since I wanted to be able to remove the countertop easily in the future, I used magnetic latches to hold it in place.  The magnets are not as strong as other types of catches, but they are easy to adjust.  And during travel, the weight of the folded A sides press on the counter to keep it solid.  To help seal against potential gas fumes, I put a strip of self-adhesive weatherstripping around the edge of the cabinet underneath the countertop.