I'm liking my A-frame fridge

[Big Red Camper]

Fred Tom and Bensinc,

Can someone help me with my questions on adding this external fridge fan?

I purchased a 12V fan from Grainger and a simple toggle switch so I can turn the fan on and off from inside the aframe.

My questions are regarding the wiring.

Attaching a PDF diagram I came up with and looking for input.
1. Red fan wire direct to post #1 on the switch
2. Hot wire/power source from 12V input direct to post #2 on switch.
3. Black wire from fan direct to 12V electrical round.

Do you agree with the above and my diagram?

Some confusion as to what wire is the 12V hot and what wire is 12V electrical ground. I have one white wire and one black and white wire going to the back of the fridge. (photo attached) I'm assuming the white wire is the ground? Can someone confirm?

Also, I'm not exactly sure how to complete the actual tap into these two wires. I see where there is a plastic piece (in the pic) where the wires connect to. This piece has six connection points (shown in pic). Would I just add the wiring to those same ports where the wires (white wire and black & white wire) from the 12V connect to as well?

Thanks - you guys seem pretty knowledgeable on this and hope one of you can assist. Sorry for my lack of knowledge but need and want to do this right.

[Pooneil]

IDK about the Grainger fan you purchased, but I highly recommend a 140 MM computer case fan for the quietness. If the Granger fan is similar, then it should be OK. The fan may not have any sound outside, but it will transmit vibration through the body of the camper that can be heard inside so quiet and a relatively slow fan RPM is a must. Plus the computer fan comes with a standard computer slip on connector and a pigtail it disconnects easily when removing the upper fridge compartment grille.

I used clamp on style taps from the auto parts store to tap the wires. In most cases of 12V, the colors are mismatched on RVs, because they use 120V colors (white for neutral or ground and black for hot or positive) rather than 12V standards. So I solder a length of white wire to the black lead and a black wire to the red lead so there is no visual confusion. The added wires are larger gauge to work with the taps and are more easily terminated to connect to the switch.

Per your diagram, you do want to switch the red (positive) lead on the fan and connect it to the black and white wire. But it never hurts to put a voltmeter on the wires to double check the polarity.

Electrical work is confusing if you are unaccustomed to it. So plan your job, as you have already done, take your time and double check (the voltmeter) and double think every step. I double check myself every time I work.

[Big Red Camper]

Thanks for your response Tom. Guess I'll have to see about the fan I purchased. I purchased a Dayton DC Axial fan that says is made for computers, cabinet cooling, etc. It measures 4 11/16" which computes close to a 140mm fan. I also considered it because it is ball bearing construction and has a high CFM air movement at 170 CFM. I figured the more CFM moving cooler air over the coils the better. The high CFM might be related to a pretty high 3800 RPM at and to your point, maybe that will create too much noise??


Thanks for confirming the wires (hot and ground). Not sure what "clamp on style taps" are but will make a trip to the auto parts store and ask.


Where specifically did you tap into with your clamp on style taps for your hot and ground wires? If you have a pic (close up) of this and those clamp on style taps you speak of, that would be very helpful.


Thanks again!

[Big Red Camper]

Tom - I actually found info on the clamp on style tap clamps you mentioned at this web site The Problem with Wire-Tap Connectors « Bareass Choppers Motorcycle Tech Pages so I know now what you are speaking about.


Still interested in seeing where you did complete your taps into the incoming 12V wires if you happen to have a pic.


Thanks again!

[mzak]

Big Red Camper, What is the amperage rating on fan? I have one computer fan that is rated at almost 2 amps and another at .1 amp. Unless I missed it in your post I did not see the amperage rating. This is also an important factor in fan selection.

[Big Red Camper]

The fan I purchased at Grainger is 1.2amps.

[Pooneil]

Yes, there is an issue with these connectors, particularly in high vibration applications. I used them because the camper is not high vibration, like a motorcycle would be, they are easily accessed and I know just where the connection is if there is an electrical failure. YMMV

Googling 140mm computer case fans gives me an estimate of 61 CFM at 1000 RPM and 0.08A draw. For about $9.00. That is more than enough flow to turn over the air in the entire compartment several times a minute. It should be sufficient to draw air over the fins.

Oh, yes, and you can get cool LED lights in the fan make it sparkle. If that's your thing.

ETA. One more thing, think about what will happen when you touch the moving fan blade. From personal expereince, I can say it just stops with no damage to it or me.

[Pooneil]

I tapped it just where your photo is. On the wire coming from the converter out of the wall to the crimp on "wire nut" connector. That connector could be replaced too rather than use a crimp on tap. But to do it according to Hoyle, you likely need a special crimp tool. I have some electrical and electronic wiring crimpers but don't know which is right for this connector.

[Pooneil]

I found the photo of my taps. It's blurry but here it is.

[Jodilc]

I DO love our HW192 fridge! It takes awhile to cool, but works well once cold. I tested the little freezer compartment by putting a bottle of water in it before we went to bed on our last camping trip. The next morning, the water in the bottle was rock-solid ice.

[mickrock]

My A122 fridge has been working perfect and I have turned the thermostat down a couple of times.
All the same, I am convinced that it might not be up to the task in high temp camping.

I'm installing a 140 quiet fan tonight per Pooneil's tips.

Thanks!

[Big Red Camper]

Hey Tom - thanks for all your help, input and pics. I just completed the external fridge fan mod. I also added quick disconnects and an on/off switch inside the aframe so I can turn the fan on and off when needed. The fan I installed from Grainger does seem move quite a bit of air and I can hardly notice any noise inside the camper.


Of course the big test will be if this helps to get the fridge temps down in hot weather. I'd also added the baffles with the Reflectix material so I hope all this helps. My fingers are crossed and I'll let you know what the results of my test are.


Thanks again!

[Pooneil]

Glad you got it sorted out. I predict a noticeable performance boost for the fridge. Last month in Colorado, I had to turn the gas to nearly the lowest setting to keep the fridge from becoming a freezer. Where did you locate the new interior switch?

[Big Red Camper]

• Tom, Fred and Bensinc,
  
  
  I could not help myself and immediately went into a test mode last night after completing the external fridge fan mod. As you may recall, I'd completed two separate tests last week without the fan mod in very high garage and outdoor temps. The fridge only cooled down to 49-59 degrees after about 20 hours of running each time..........something had to be done...........
  
  
  In short, all I can say is WOW!!!
  
  
  Below are my results of my test last evening using my house current for a power source. This test was in my garage. The garage was very hot and without any natural air movement that you'd typically have in an outdoor test. Understanding that, I consider this test to have taken place under extreme circumstances:
  
  Time Garage Temp Fridge Temp Fridge Setting
• 6:30pm 95 degrees 95 degrees 7
• 7:45pm 94 degrees 69 degrees 7
• 8:30pm 93 degrees 56 degrees 7
• 9:30pm 93 degrees 46 degrees 7
• 10:30pm 90 degrees 40 degrees 7
• 11:30pm 90 degrees 37 degrees 7
• 1:00am 88 degrees 34 degrees lowered to 3
• 7:00am 82 degrees 38 degrees 3
• 8:00am 83 degrees 40 degrees raised to 5
• 8:30am 83 degrees 37 degrees 5
  
  As you can see, the results are awesome! Only 5 hours to go from an internal fridge temp of 95 degrees down to 37 degrees in a closed garage that was stifling hot!. I now have the confidence that the fridge will perform under almost any hot temperature environments. I am sooooooo jazzed about this!
  
  
  I'm not much of an electrician and your help and communications were much appreciated! Thank you all again!

[Dodaman]

Glad it all worked out. I love my fan mod in the hot temps, keeps the fridge in our PUP at the correct temp. And is quiet and barely draws 1/2 an amp. I fan a switch to a thermostat, too. So it can cycle on/off on its own or leave it on all the time or off.

I'll be posting pics soon. Post some pics when you get the chance. Thanks.

Travel safe.

Mark

[Pooneil]

Given the time it takes and the benefits, it's one of the best mods you can do.

Glad it worked so well for you.

[Big Red Camper]

Mark, attached are the pics you asked for (main power tap, fan with disconnects, internal on/off switch) Also attached is a PDF of the wiring diagram I used.


Tom - sorry forgot to answer your question. I picked up the switch and switch plate at the local AC Nelson camper sales company.

[Big Red Camper]

Fred and Tom,


Thought I'd let you know how this fridge mod worked during an actual camping trip.......fantastic!


We were camping for three days this past week. Temps were between 88 - 92 degrees. Fridge only took 3 1/2 hours to cool down to 37 degrees prior to leaving for the trip. In the past, the pre-cool down would take approx. 24 hours and never get down to a cold enough temp prior to departure.


Internal fridge temps at the camp site were consistently between 34-39 degrees depending upon how often we went into the fridge.....which was quite often. Seems with the hot outside temps, I had a constant urge to keep pulling cold ones out of the fridge!


I ultimately had to adjust the fridge temp control down to level 4 to keep the fridge from freezing temps.


Thanks again for all your help and input. This was a very enjoyable trip knowing that we could count on a fridge that would keep up during the heat of the day.

[Pooneil]

You're welcome. Glad things worked for you.

It's the best and easiest mod around.

Happy camping.

[pgandw]

I'm glad to hear the fan works so well. I anticipate I will be installing one next winter/spring to get the more consistent performance you guys are seeing and I am not. Our next 3 trips are Rocky Mountain National Park (mid-August), Mt Rushmore (late Sept), and Southern Utah (early Nov). Nights will be cool to cold, so I'm not too worried about the fridge fan for these trips.

Right now, I'm trying to figure out whether the minivan is carrying the fridge on DC, or whether I'm taking the camper batteries down before I even arrive at the site.

Tom - did you pick 140mm fan because it fit better than the 120mm? I ask because I still have several nice unused 120mm fans from building my own computers.

trying not to learn everything the hard way
Fred W
2014 Rockwood A122 A-frame