Noisy Refrigerator Vent Fan

rseagle · 04-23-2004, 06:02 PM

OK, let's do some Brainstorming here.

We like to Boondock and enjoy the peace and quiet of our favorite secluded mountain campground in the Summer. I'm afraid, that the noisy refrigerator vent fan in our 22' CCD is going to drown out the natural sounds we travel so far to hear. Our first trailer, an SOB, had a vent stack to the roof with no fan. It was dead quiet so we could hear the stream, Whip-Poor-Wills at dusk, Cicadas, wind through the trees, etc. You get the picture.

I've read of retrofitting the 12v fan with a 24v fan, which rotates at a slower RPM, but twice the Amps. It still makes noise.

I'd thought of fabricating a 4-6' metal or plastic vent stack that could be temporarily attached to the CCD when we get to the campground that would draw out the hot air behind the refrigerator. Is this practical? Could it work like my SOBs stack, so that the fan's thermostat would keep it from coming on?

Any other ideas from you "Out of the Box" thinkers out there?

Thanks,

Bob

mandolindave · 04-23-2004, 06:55 PM

My 1973 20' has an intake vent underneath the fridge and an exhaust vent on the roof. The original fridge had no fan. The new fridge has a fan. The
installer said that I really only needed the fan for hot days. I didn't
want to be running the fan and using up my batts so we are installing
a manual swith to kill the fan when I need too.
It would be nice if you could hear another trailers fan , to see if
you have a funky fan.

Turtle · 04-23-2004, 08:24 PM

I'm adding a switch to my refrigerator fan on my trailer tomorrow. Our trailer is so small you can't get away from the fan. As I've detailed on another (see thread "noisy refrigerator fan"), I moved our fan to a quieter location which really helped. We really only need to turn it off for sleeping.

MaShep · 05-03-2004, 12:03 AM

Hey Jamie:
Would be cool if you take a few pics of your project? I'm also wondering, how much noise does your water pump make when you turn on the faucet? Ours is extreemly loud!

Pahaska · 05-03-2004, 08:33 AM

The fan runs a lot faster than is needed. One approach is to put another 12v fan in series with the first; both will run slow and without noise. Another option is to put a resistor in series with the existing fan to slow it down.

Do a search ... there are a couple of long threads on the fan noise problem.

Xray · 05-03-2004, 09:53 AM

Here's my solution for our '04 22' CCD fridge fan noise (quite loud!):

SilenX 120mm 11 dBA Fan $26.00
Part number: 0000375

11dBA is virtually silent.

I ordered it from EastLuna.com. According to my measurements, it should be a direct fit as a replacement for the factory original.

Best regards,

X

luckydc · 05-03-2004, 01:46 PM

X

Please let me know how that works out. Had the Bambi out boondocking this weekend. The fan ran contantly, I assume because the gas flame. Eventually, I had to discontent it and turn down the frig so I could sleep.

Very interested in the SilenX. Appropriate name, too!

luckydc · 05-03-2004, 01:55 PM

X:

Couldn't wait. Ordered one. Thanks for the tip.

rseagle · 05-03-2004, 03:19 PM

X:

Is this fan for Direct Current (DC) use? What is the amperage draw?

Bob

luckydc · 05-03-2004, 03:28 PM

Bob:

From the site:

SilenX fans are the perfect complement to SilenX power supplies in your system! Featuring a noise to airflow ratio no other fan on the market can touch (papst, panaflo and blacknoise don't even come close!), these are the perfect fans for your silent PC. Each SilenX fan comeswith silicone composite fan vibration dampening mounts, no other fan on the market comes packaged with such mounts! 3->4 pin convertor in included with every fan so you have the option of running it off the motherboard of the power supply, this is one amazing deal!
Features:
Fan Swept Forward Fan Blade Design
Smoother, Thinner Fan Blades
Highly Efficient Hypro Bearings
Vibration Isolation Mounts

Specifications:
Fan Dimensions: 120 x 120 x 25mm
Fan Input: 12V/1.2W
Fan Speed: 1400 RPM
Air Flow: 40 CFM
Noise Level: 11 dBA
Three Pin Connector
Four Pin Connector

What is the ampage of the factory fan? Boondocking this weekend didn't even put a dent in my batteries, so not certain I'm concerned about this fan being a big draw. I want quiet!

dtbw · 05-03-2004, 03:29 PM

This fan is for use in a PCs where all the fans are DC driven. The manufacturer's website specs this fan at 12V/1.2w so that mean 100ma of current. I have order a pair of these. I previously replace the factory unit with a lower rpm, high volume unit (a big improvment), but I think I can still improve it more with these fans. My hope is that with 2 running in series, I can virtually eliminate the refrig fan noise while still providing a good flow of air thru the refrig condensor.

david

rseagle · 05-03-2004, 03:51 PM

The Silenx fan looks like a good solution! Might have to give it a whirl. Sorry about the Pun!

I pose another idea: Could a rheostat (variable resistor) be used with the existing fan to slow the RPMs to a quieter speed? It might be a cheaper alternative then 1 or 2 Silenx fans $26 ea)?

Bob

dtbw · 05-03-2004, 04:14 PM

The factory fan is a plain vanilla design. The blades are not designed for quiet operation or large volumes of airflow. Slowing it down will cut some of the noise, but it cut the flow of air faster than the reduction in noise. You need a better blade design. As I mentioned, I already replace my factory fan with a lower rpm, high volume design, which made it much quieter inside, but outside sitting under the awning, it was still a nuisance. The key is lots of slower moving, high efficiency blades designed for quiet running. Putting two of these in series may still not result in quite as much airflow as a single unit running at full speed, but the air will be distributed over a greater area, so the result should be satisfactory cooling.

david

thenewkid64 · 05-03-2004, 05:27 PM

Quote:

Originally Posted by rseagle

I pose another idea: Could a rheostat (variable resistor) be used with the existing fan to slow the RPMs to a quieter speed? It might be a cheaper alternative then 1 or 2 Silenx fans $26 ea)?

Yes, but at the cost of loss of power. depending on the type of variable resistor or Potentiometer you use the loss in voltage is normally done by a resistor that generates more heat. So you get 70% efficiency to be quite but still have the same draw or load on the batteries. If you are boondocking it can make a difference. It will be a lower cost alternative, but as mentioned in other posts you reduce the airflow. The reduction in airflow can make the refer work harder to keep the food cold. I guess what I am trying to say is TANSTAAFL. You are going to have a cost somewhere. So I would go with 2 in series or the quieter fans IMHO.