Adding a fan to the fridge

**Stefrobrts** · 03-21-2004, 05:58 PM

I'm adding a fan to the fridge to help it cool better, because it's performance last year wasn't quite up to snuff. On a hot day, even cranked all the way up I couldn't quite get it below 40 (we spent a lot of time using an ice-filled cooler last year). So I'm going to try adding a fan. But now that I'm looking at it I have a couple questions.

Here is a picture of the back of the fridge. I saw in another post the fan should blow a gentle breeze over the fins. Does it have to be mounted right by the fins, or can I put it at the bottom of the compartment above the screen and just let it blow upwards to get the air moving?

Also, the big square box above the burner has a little round tube on top (it's closest to the camera). Is this like a chimney or something? It's just sitting there loose with a piece of wire sticking out of it. It looks like it is missing a screw that would hold it down. I thought I should screw it back down? Just thought I would ask first since I'm asking about fan placement.

thenewkid64 · 03-21-2004, 06:06 PM

Steph,

Air movement is what you are after. A fan blowing up creating additional air flow helps. Since you have such good access I would try to not only blow air up, but if you can, direct it over the fins at the same time. The other benny of a fan is it helps to keep the heat that rises from overheating the flue and having the heat collect in the trailer.

As for the round chimney, that is the top of the flue for the gas heater on the fridge. The box below it is an insulated cover over the heat exchanger. The wire, if you pulled it up, has a flat bar with a twist to it and it just fits in the tube. This twist causes the rising heat from the flame to swirl in the heat exchanger and evenly heat the walls. This evenly heats the coolant. The wire and it's attached spiral should be able to rattle in the tube. This is normally removed to allow for flue cleaning.

If you want a quiet fan look for a 24 volt one. It will run at half speed and should be whisper quiet.

**Stefrobrts** · 03-21-2004, 06:52 PM

Right now I have a surplus 4 inch 12v fan, and it blows way more air than I need, and it's loud. I tried stepping it down with a 9v adapter from radioshack (plugs into a 12v plug and only lets 9v through) but the fan still blows harder than I think is necessary. I was hoping to find a dimmer-switch type 12v switch to let me adjust it by hand, but they didn't have one. Maybe I should look for a 24v fan and try that.

thenewkid64 · 03-21-2004, 06:59 PM

If you are going to have AC power all the time the 9V power adapter would work, but if you are boon docking you will want to have it run off the Battery.

A 24 volt muffin fan should be able to be found at most surplus electronics places.

The trouble with a 12VDC speed control is that it reduces the usable voltage and creates additional heat to do it. Beside 12 VDC dimmers that can carry the amperage for the run times will not be cheap.

You could wire 2-12 volt fans in series to slow them down some. or get a BIG dropping resister to reduce the voltage. Remember to keep the resistor off of any flammable surface, it WILL get hot.

**Stefrobrts** · 03-21-2004, 07:19 PM

What kind of a setup do you have behind your fridge? I remember seeing a post where you showed a picture of it, but I can't find it now with search.

So a couple fans in series would be slowed down and quieter? 24v or 12v fans, or does it matter? Oy, I think I'm getting more confused...

And when you say it would be even better to direct the airflow over the fins, do you mean like maybe a baffle that would direct all the air coming up to go over the fins would be a good thing? Because I'm sure I could swing that.

Pahaska · 03-21-2004, 08:19 PM

I would use a pair of 12v fans in series. They will be super quiet and move plenty of air for the purpose. I have done this previously on my Trailmanor.

I actually have 4 2" square muffin fans in the shop that I bought, along with huge heat sinks, for $1 each at a computer salvage place. I am going to install them as two parallel pairs of two in series. I have an in-line thermostat that I am going to clamp to the tubing so that the fans run only when needed.

Silvertwinkie · 03-21-2004, 08:24 PM

John,

You still think you need that with the roof exhaust on the Classic?

I suppose every little bit helps, but I had thought that since your new unit and mine have a more conventional setup (roof exhaust), fans might be a bit overkill.

Have you had any issues with cooling?

Eric

WayWard Wind · 03-21-2004, 08:37 PM

John, I'm surprised that your 03 did not have a fan w/ thermostat installed at the factory. Our 02 Bambi came with a fan & thermostat installed. The problem I found was at night when the fan would run, it very annoying. At first I opened the top & bottom outside doors to let the heat move thru. This shut the fan off, but I was concerned via the critter thing, so I just removed one side of the thermosat wire for the night. Before we start this season I'm going to put a switch inside to shut the fan off. I know it defeats the purpose of the fan, but it's just to annoying. I really do not feel I can get a fan quiet enough for me to have a restful evening. Steph, if you need to wire a fan, you may want to think about having a off & on switch inside the trailer. Just nice to have control without going outside, or digging in the fuse box. If you need a pic of a fan installed l can get one posted.
Best,

Pahaska · 03-21-2004, 08:59 PM

The Classics have the roof vent and no fan; however, on my Scamp, I found that even with a roof vent, a fan helps a lot in our Texas summer heat. On the Scamp, I could get 3 or 4 degrees more cooling and there was less transfer to the interior of the trailer with the fans running. Before the fans, I could just about cook in the pantry in the Scamp. Cool-down with the fans is a lot faster, also.

Also, I have the fans and I might as well use them. They are so quiet in series that I'll never hear them run. For the few minutes that it will take to install them, I figure they will pay off in the long run.

Pahaska · 03-21-2004, 09:03 PM

Quote:

I really do not feel I can get a fan quiet enough for me to have a restful evening.

I seriously doubt that you will hear 2 12v fans in series. Running them in the shop, they are so quiet that I have to look at them or put a hand over them to know they are running.

**Stefrobrts** · 03-21-2004, 09:09 PM

Thanks for the advice. I'll see if I can find a couple 12v muffin fans to replace this one big fan I have.

I'm going to have a switch inside the trailer to turn it on and off. There's a switch for the furnace fan on a panel next to the furnace. I'm thinking I will mount the fridge switch there also, for easy access, and that's where I'm going to be tapping into the 12v power anyway.

A.E., a pic of the fans installed would be great. Like I said, I know there's a thread with pics of Brett's fans installed, but I can't find it.

Silvertwinkie · 03-21-2004, 09:15 PM

I see John...thanks for the info.

thenewkid64 · 03-21-2004, 09:35 PM

Here is the requested link!

http://www.airforums.com/forum...an+and+bracket

It is about 3/4 of the way down

WayWard Wind · 03-23-2004, 07:18 PM

Steph--I took some pics of the fan in our 02 Bambi & I'll try to post them. hope they
Best,