Hot weather refrigerator performance

[dlb53151]

Hi Merlin - My email address is dlb53151@yahoo.com.  For everyone's benefit here the fan I am referring to.
Here's the view of back of fridge from top vent.

Here's view from bottom vent.

Here's how I mounted the one fan (after splitting apart) on the top vent (blowing out).
I mounted the other fan on the bottom vent in the same manner, with zip ties (blowing in, however).

Thanks for your input Merlin.  This is a must-do mod for anyone traveling in hot climates.


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[Merlin]

At the bottom of the middle photo you can see the orange/white wire DC terminal block I referred to earlier. I'm working on how to resize photos so I can post. I'm such a Luddite when it comes to digital photos......I miss my darkroom. 

How does Tapatalk work? 

[Diversteve]

Update on fan installation.
I added this temperature controller.

HiLetgo 2pcs W1209 12V DC Digital Temperature Controller Board Micro Digital Thermostat -50-110°C Electronic Temperature Temp Control Module Switch with 10A One-channel Relay and Waterproof

I wired the controller in the circuit after the toggle switch.
Now i don't need to remember to turn it off when the temperature is cool enough for the natural circulation to keep the area cool.

[dlb53151]

Diversteve - can you please share pics of your controller installation?  Haven't installed my controller yet.


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[LoneWolf04]

I'm currently modding my fridge. Spent $80 and the mod consists of:

4x Coolerguys 80mm x 25mm IP67 rated fans
2x Coolerguys 80mm x 15mm standard fans
4x 3 PIN Y Splitters
2x 3 PIN to Bare Wires

The 80mm x 25mm fans fit pretty much perfect between the cover outlet and lines up with the position on my condenser fin. They are secured with zip ties at the bottom and a thin bead of caulk at the top. To increase forcing air out the vent and not having it deflect back into the fridge compartment I used foil tape. The tape also helps securing the top of the fans on top of the caulk.

The 80mm x 15mm fans I mounted alligator clips to them in order to clip them to the interior cooling fins to circulate air.

I plugged into the circuit board to 12V pin that was not being used labled (lamp/heater) and is only active when the fridge is turned on. This way the fans are on when the fridge is turned on. I do not boondock so IMO to reduce the stress on the fridge's cooling system it was not worth the money or stress on the fridge components to not keep these fans running all the time to help fridge temps and circulate air.

[Merlin]

Wow, THAT should help a lot.

[LoneWolf04]

Wow, THAT should help a lot.

So far the outside compartment temp has been 15-20 degrees cooler, even with all the hot and humid temps through Michigan. That compartment drop has resulted in the fridge temp being a couple degrees cooler.

Inside fans are getting installed today and expecting that to drop the temp a good amount.

[GrampaKilt]

Agree with WOW. Great idea with the aluminum tape. GK

[Diversteve]

Sorry for the late reply.

[Chappy133]

When we bought our 21 RBS used last year the seller disclosed that they had replaced the circuit board for the Dometic refrigerator. 

Last fall I was camped the military campground in Key West in September and October.  The weather was unseasonably hot for the Key.  The refrigerator was struggling to stay cold.  We were using shore power with the frig on auto.  Had a retired RV tech talk me through trouble shooting and we were able to determine it was the "thermomister" probe on the fins inside the frig.  Overpaid for a replacement part from an RV supply company, turns out the same part is available on Amazon for a much lower price, and installed the replacement with some challenges or running the wires to the board.

Everything worked fine until we got back in the heat of the Keys this winter and the daytime temperatures started to climb and by sunrise had barely gotten back in to the upper thirties.

Fortunately for us our neighbor, who are full timers, is an RV tech.  We had her come over and check our refrigerator out and she determined the fan to move air was no longer working.  To replace that fan would require removing the frig to do so and it was agreed to just abandon it in place.  With the use of a step ladder and small electric fan placed at the bottom of the frig with the access cover off to move air up the back over the fins.  This worked well.

I then decided to remove the top vent cover since I could not see any daylight when looking up from the bottom access panel.  Once the cover was unscrewed which was made difficult by someone at the factory thinking it was a good idea to fill the screw holes with lap sealant making the screw removal take four times as long as it should of.  With the cover finally off I discovered that the fins were ¾ blocked at the top by fiberglass insulation.  Appears that when the refrigerator was installed and slide in the insulation on the top sides pushed back and laid on top of the fins greatly reducing convective air flow (see enclosed picture).

With the use of a coat hanger fished through the wire mesh I was able to push and prod the fiberglass insulation off to the sides.  Needless to say the refrigerator performance has greatly improved now.  Stays in the 36-38 degree range now regardless how hot it gets here now.  This is a black trailer with the frig in the sun from late morning until Sunset.

Also installed two new fans.  One at the bottom and one at the top.  Both have a thermomister probe for putting the fans in the auto mode.  A manual mode option is also available. 

Decided to put a squirrel cage type fan on the access panel to pull air in and up: https://www.amazon.com/dp/B0C6T1LLMX?psc=1&ref=ppx_yo2ov_dt_b_product_details

For the top vent a more standard type square fans:  https://www.amazon.com/dp/B09NLFDLD1?ref=ppx_yo2ov_dt_b_product_details&th=1

So far very pleased with the results. 

[Chappy133]

Forgot to add the RV Tech believes both the theromister and board issues with the frig was due to this blockage.

[Merlin]

Good work. And good trouble-shooting. Classic install error at LL.