Refrig fan noise FIXED...really

[BobRay]

This might be a good alternative to the parallel/series switch.

It gives you infinite control of the fan speed for about $5.

Zalman Fan Mate 2 Variable Fan Speed Controller

[Wayne&Sam]

If boondocking battery life is important, this might not be as good as a low draw fan that is quiet. Even though you slow the fan down with this, you're still burning more battery than you have to.

[mikenicholso]

This was my first modification to my new to me 2007 23' Safari SE. After the first night in the wild listening to that bag of chipmunks in the fridge my first stop was Frys to pick up some new fans.

[TG2500]

Other threads have mentioned 1 silenex fan is enough and it fit perfectly into the existing brackets on my new 19' Bambi. The difference in sound is amazing - now you can't hear it running.

Have others found that the 1 fan is enough? I'm in New York State. We get hot in the summer but nothing like southwest hot.

[Silvertwinkie]

Originally Posted by campadk

Great thread!

Interestingly, this topic is more than 3 years old. You would think that by now Airstream would be using something other than a dumb, noisy, battery sucking fan... but no.

You know, as I read this thread, I was wondering the same thing since the factory folks clearly read this forum and I am sure Airstream owners, being as vocal as we are here must have said something to the factory folks since this has gone on for years and years now.

[A.L. Mayfiel]

Originally Posted by dtbw

Although a thread was started on this subject, it really belonged in this section. I am going to describe and attach pics showing how I totally FIXED the noisy fan issue and actually improved airflow at the same time.

Using SilenX fans (www.silenx.com), I created a new refrig cooling unit that utilizes 2 of the 120MM 11DBA fans. I purchased mine directly from SilenX for $55.75 including shipping. These fans are large volume, high efficiency fans with quiet blade technology. They also come with silicone mounts to further isolate any noise produced.

My goal was to eliminate BOTH inside AND outside noise as both were major issues with my '02 Bambi (shared with all recent models lacking roof ventilation for the refrig).

In designing my new cooling system, I made a significant change from the original design in that originally, the fan mounted vertically and PULLED air thru only the center 4" of the refrig condensor. The design of the outside door greatly restricted the airflow exhaust plus it forced the air downward where it could be immediately pulled back into the lower louvers of the vent and circulated back thru the condensor (ie a hot air short circuit). In my new design, the fans are mounted BELOW the condensor and PUSH air thru almost 9" of the condensor. I also eliminated the potential for the hot air short circuit by blocking the section of the upper access door residing below the fans (ie incoming air NOW is pulled from the lower door which is about a foot lower). All of this will be clearer in the pics.

As I was installing 2 fans, I also added the ability to run them either in series or parallel (electrically speaking). Running in series, they run quieter while still moving significant amounts of air. In parallel, I have max cooling and very acceptable low amounts of noise.

Results...FAR better than anticipated. Even when running full speed (ie in parallel), the fans are virtually silent. You have to put your ear DIRECTLY against the upper door louvers to even hear anything. In series mode (half speed), there is simply ZERO noise...PERIOD. Inside, running full speed in parallel mode, you can barely hear a slight noise, BUT it is MUCH quieter than even the Magnetek converter fan. In series mode, NOTHING inside or out.

Okay for the details. I purchase aluminum angle stock, aluminum bar stock and aluminum sheet stock at Home Depot.

Using the aluminum angle stock, I made two brackets that actually hold the fans. I cut away the section of the aluminum that would otherwise have blocked a section of airflow on both fans. Using the included silicone mounts, I mounted each bracket to the fans. As the two brackets are NOT attached to each other and the silicone mounts are very flexible, I also made small brackets that mount on the top of the fans as well as the side aluminum brackets. This provides rigidity at the expense of some of the noise isolation capability of the silicone mounts (minor).

Using the aluminum bar stock, I cut a length the width of the upper door opening and riveted it to the fan assembly backets already constructed. This acts to support the front edge of the fan assembly. I also cut another section of bar stock and bent it to form a support going vertically from the backside of the fan bracket thru 2 bends such that it arrives at the same plane as the solid bar attached previously, but several inches lower. This bracket acts as the rear support for the fans. The fans do NOT touch the refrig at ANY point as this could allow noise to transmit thru the refrig to the inside of the trailer.

The final additions were some baffles to direct the airflow more precisely. The new fans, being slight wider than the condensor above needed a small baffle to ensure that all the airflow was THRU the condensor and NOT creating a air barrier to escaping hot exhaust air from the condensor. You can see this baffle located in the center section of the horizontal mounting bar. I also added another baffle at the top of the refrig cabinet as the original baffle left a dead air space that trapped hot air above the upper louvers of the access door. I made a baffle that extended from the top edge of the upper door to an area just above the rearmost portion of the condensor and then angled it downward to where it was 1/2" or so above the top of the refrig. This pretty much mirrored what A/S installed, but mine eliminated the dead air issue. I left the original top baffle in place. You can see this baffle in a follow on email as I already have the max 5 attachments on this post.

BTW, the curvature seen in the pics is a artifact of my wide angle lens

After removing all the original fan hardware, I installed the new assembly as shown in the attached pic.

david

David thanks for your research and experience. I will be using your sugestions for the fans in my Bambi.

[Wayne&Sam]

I replaced the original fan with one Silnex and it works fine. Outside it is virtually silent, but inside you do hear some noise. It must be some acoustic thing going on because you can't hear that pitch from outside. Still, it's a big improvement.

[mikenicholso]

One thing is for sure when it comes to Airstream owners. We are a very creative lot.

[Bill&Dalene]

I want to thank all the folks who contributed to this post. I replaced the factory fan in the frig with a Silenx fan I picked up on Amazon. What a difference! I can't believe I've spent the last year listening to that racket at night (or turning the frig off when we couldn't sleep) and now - beautiful silence. I have to open the outside vent every once and a while to convince myself the thing is running. Took less than 30 minutes to do the swap out.

Thanks again for all the help.

[jglabrown]

Bill&Dalene,
Which Silenx model did you end up buying?

[3 Dog Nite]

This is some great information. I've removed the upper cabinet & tambors above the fridge in my Tradewind. Don't much care for seeing the plastic duct that leads to the roof vent. I think I'll go with this fan idea & duct the heat out the side of TT using a hood vent cover.

Boy the way the ideas here keep on evolving is amazing.

Ricky

[ncbambi]

Just got back from a 1 month trip and didn't even give the refer fan until I got this forum update. Realized that I had Out Of Doors Mart in NC "fix" my 2008 safari blast summer. This is the first trip since then, and didn't even think about checking it out - no sound at all to remind me.. Well the reason there was no sound is because they fixed it all right, they cut the blue cable - needeless to say the fan was "quiet.". Can't believe it, that service trip cost me a lot - dead fan, inferior repair on shower and a 2-1/2" scratch and dent in my brand new trailer.

So thanks for the post - will make another trip to JC to repair the remaining warranty work before the 2-year warranty is up in December! I will never go to ODM again.

[Bill&Dalene]

To answer jglabrown's question:

I bought the ixtrema 120 (9dBA and 38 cfm). The 38 cfm has less pull than the OEM fan, so I'm ordering the silenx ixtrema pro (14 dBA and 72 cfm) just in case I'm in hot weather. So far the low cfm hasn't caused an issue, but we haven't had temps in the 80's yet here in the NW. Just being cautious because that's the way I am. Plus, the 9dBA is SO quiet, I don't think the 14 dBA will be a problem, especially after the OEM airplane prop.
Bill

[Spot]

I fried my new replacement fan. After reading this post, I replaced my original "blaster" fan with a 120mm Papst that I had laying around from home computer building. Much improved. Still not happy, I went to my favorite computer parts vendor Newegg, and bought a Scythe S-Flex SFF 21S fan, 1600RPM, 63.7CFM, 28dbA for $19.95. It came with a typical red/yellow/black wire connector that I snipped. I should have read up more, because I hooked two wires (red and yellow), heard a small "pop," and observed a small amount of curling smoke from the fan. Dead, due to stupid installer. So, I need to confirm what I think that I need to do next time: Snip off the yellow wire. Connect the red wire of the fan to the thermo-switch, then connect the black fan wire to the formerly blue side ( I believe that an inline fuse is on that side). Can anybody out there confirm this?

[Spot]

Correction: the fan model is a SFF-21F. This fan uses a fluid dynamic bearing made by Sony that boasts 150,000 hours of use. Nice.

[Spot]

Bumping!

[jglabrown]

Great thread! We took a plunge and ordered the Silenx 14dBA fan from Amazon. Easy to install although the one we received did not have color-coded wires. The only problem we have is that the fan is so quiet I spend too much time opening the vent to see if it's still running.

[Bill&Dalene]

Hopefully you're not waking in the middle of the night to run outside to check the fan.

[Dave Park]

Originally Posted by Spot

It came with a typical red/yellow/black wire connector that I snipped. I should have read up more, because I hooked two wires (red and yellow), heard a small "pop," and observed a small amount of curling smoke from the fan. Dead, due to stupid installer. So, I need to confirm what I think that I need to do next time: Snip off the yellow wire. Connect the red wire of the fan to the thermo-switch, then connect the black fan wire to the formerly blue side ( I believe that an inline fuse is on that side). Can anybody out there confirm this?

Consider it confirmed!

The yellow wire is a speed sense output wire. Putting 12v across red to yellow burns out a coil.

You need to attach the red wire to the thermo switch and the black wire to the blue wire.

Hope this helps.

[Spot]

It does indeed help! I did just what your described to short the first fan out. Too much haste, not enough thinking.