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Jo Mojo · 10-27-2010, 06:35 PM

Actually, I'm not a 'fan'. We have a brand new 2010 Airstream and the refrigerator fan hums pretty loudly and sometimes can get a good, loud 'honk' going. We have taken to turning the refrig off at night just so we can sleep. This works ok unless we forget to turn it back on in the morning

The last two nights we turned the refrig off but the fan kept going ALL NIGHT LONG anyway?!?

Anyone else find this annoying? Are there any fixes out there? And why would the fan keep going even if the refrig is off?

Any insights would be much appreciated!!

Frank McFee · 10-27-2010, 07:40 PM

Jo Mojo
My fan has a switch by the door (red lighted) that turns off the fan. However, there is a low temperature cut off switch in series located next to the fan which cuts off if the air cools below a set point when the switch is on. That will turn the fan off on cool nights. Please note my switch was mis-wired from the factory and the fan was always on in either position. I reconnected the wires and it works fine now. I only use my fan on hot humid days. You might check the wiring. The fan noise is only noticable when sitting outside under the awning.
Frank

Ahab · 10-27-2010, 08:04 PM

If you don't have the 0ff switch, simply go outside, open the top access hatch, by the refer, you will see a finned unit about eye level, there is push type connector on the rear fin. Simply pull it off and presto, no fan noise. This is a thermo-couple device which is supposed to turn the fan on if the outside temp ios above 85 degrees.

ncbambi · 10-27-2010, 08:37 PM

We had the same problem. ordered a silenex fan and had it put in - presto, no fan noise. Do a search for silenex and the thread will detail the what and where to buy. Easy to install.

aftermath · 10-27-2010, 09:31 PM

OK, here it comes.........What Fan? I don't think I have one on my 2006. Is this something that is in the outside compartment to increase efficiency? Is it in the fridge like ones at home? If I do have one, it must be very quiet!

SilverRanger · 10-27-2010, 10:28 PM

Quote:

Originally Posted by aftermath

OK, here it comes.........What Fan? I don't think I have one on my 2006. Is this something that is in the outside compartment to increase efficiency? Is it in the fridge like ones at home? If I do have one, it must be very quiet!

Unless they changed things around, you should have a fan in he outside compartment near the top of the refrigerator. Mine resembles a box fan such as those used in computers. I know we're talking about different models, but on my 2005 there is also a lighted switch just inside the door on the left. The fan is heat activated, so it may not be running all the time, even when the switch is turned on. On most models, the fan is rather noisy. If it's turned on, you should be able to hear it when it is running.

TBRich · 10-28-2010, 01:54 AM

There is a lot of discussion here about the fan noise and different replacements that many owners have made... Do a search and you'll find them... here's one to get you started: http://www.airforums.com/forums/f425...fan-36897.html

We replaced ours...so nice to have it quiet!

Jo Mojo · 10-28-2010, 04:49 AM

Thanks to everyone for your great information...this forum really is quite amazing!

It is dark and mosquito infested now, but will check the box when the sun comes up. For the first time we are in a place that is hot and humid, though not 85 degrees at night thank goodness...what happens to the frig if it is humid and about 65 degrees at night and the fan is not on? Any downsides to frig operation or frig life?

Thanks!

Jo Mojo · 10-28-2010, 05:20 AM

Found the answer to my own question on the Snyder website:

How RV Refrigerators Work
These units are unlike the ones you find in your home. They have no moving parts, run on both propane and electric. They use ammonia as the refrigerant, and what circulates the ammonia is heat. The mixture of ammonia and water is heated in a boiler by a propane flame or a electric heating element. The mixture boils, and the strong ammonia rises as a vapor into the condenser on the top rear of the refrigerator. Here it turns into almost pure ammonia. It exits the condenser, travels into the freezer coil first, then what liquid ammonia is left travels into the coils for the refrigerator section. After it passes thru all the internal coils, it turns back into a vapor again, because it absorbed the heat inside the refrigerator. At this point, the ammonia vapor is attracted to the weak water mixture in the absorber tank, and the process repeats itself.
What happens in hot weather - Often during hot weather spells your refrigerator section will rise above 40 degrees, this is because the condenser relies on ambiant air temperature to convert the hot ammonia vapor to a liquid. The hotter the air, the less liquid ammonia the condenser produces. So since the freezer is first in line for the liquid ammonia to run in, often it boils off and there is nothing left for the refrigerator section. Your freezer stays cold, but your refrigerator section gets warm. In extreme cases, the freezer section also warms up.

Most refrigerators are mounted in enclosures, and the sun beating on the coach will easily make the air temperature exceed 100 degrees.....the manufacturers maxium temperature rating. Also venting designs have a factor. Side vented units such as found in ROADTREK and AIRSTREAM have more temperature related problems than the more common roof vented coaches.

pretty cool actually...I have ordered one of their cooling kits...now I just need to find someone to install it...I am completely lame in that dept.

lewster · 10-28-2010, 07:11 AM

Quote:

Originally Posted by Jo Mojo

Found the answer to my own question on the Snyder website:

How RV Refrigerators Work
These units are unlike the ones you find in your home. They have no moving parts, run on both propane and electric. They use ammonia as the refrigerant, and what circulates the ammonia is heat. The mixture of ammonia and water is heated in a boiler by a propane flame or a electric heating element. The mixture boils, and the strong ammonia rises as a vapor into the condenser on the top rear of the refrigerator. Here it turns into almost pure ammonia. It exits the condenser, travels into the freezer coil first, then what liquid ammonia is left travels into the coils for the refrigerator section. After it passes thru all the internal coils, it turns back into a vapor again, because it absorbed the heat inside the refrigerator. At this point, the ammonia vapor is attracted to the weak water mixture in the absorber tank, and the process repeats itself.
What happens in hot weather - Often during hot weather spells your refrigerator section will rise above 40 degrees, this is because the condenser relies on ambiant air temperature to convert the hot ammonia vapor to a liquid. The hotter the air, the less liquid ammonia the condenser produces. So since the freezer is first in line for the liquid ammonia to run in, often it boils off and there is nothing left for the refrigerator section. Your freezer stays cold, but your refrigerator section gets warm. In extreme cases, the freezer section also warms up.

Most refrigerators are mounted in enclosures, and the sun beating on the coach will easily make the air temperature exceed 100 degrees.....the manufacturers maxium temperature rating. Also venting designs have a factor. Side vented units such as found in ROADTREK and AIRSTREAM have more temperature related problems than the more common roof vented coaches.

pretty cool actually...I have ordered one of their cooling kits...now I just need to find someone to install it...I am completely lame in that dept.

Stu's very simplified version of the gas/absorption refrigeration process will at least give you an idea of how your RV fridge gets cold. He did leave out one VERY IMPORTANT aspect of the process though, and that it the presence and function of hydrogen in the mix. It is the combination and chemical reaction of the hydrogen with the concentrated ammonia that creates the intense cold. It IS NOT ACCOMPLISHED by ammonia alone.

The over heating of the condenser is what negatively effects this process, and his cooling fan kit will help this process. If you use your trailer in very hot ambient conditions or park it with the sun on the refer side, you might also need a second fan placed on the upper vent door that will help exhaust the warm air from the refer compartment, as his kit will not keep up with the elevated ambient conditions. It can be wired in with the Snyder fan kit and will almost guarantee that you have no more problems with your fridge temps!

aftermath · 10-28-2010, 09:05 AM

SilverRanger,

Thanks for the info. I have only had my trailer for a year now and even though we have been out 22 times, I have never heard the fan. Apparently it is turned off but I don't even know that for sure. We did stay at Mt. Shasta and the outside temperatures were close to 100. The fridge functioned well even in the heat.

I have winterized it and put it away. I will be checking first thing next spring. Thanks for the guidance.

pattonsr · 10-28-2010, 10:49 AM

Lew,

Does the refrigerator need to be pulled out to add a Snyder and second fan to a 2011 27FB Classic? If so, is that a big deal?

Barry

lewster · 10-29-2010, 06:15 AM

Quote:

Originally Posted by pattonsr

Lew,

Does the refrigerator need to be pulled out to add a Snyder and second fan to a 2011 27FB Classic? If so, is that a big deal?

Barry

Barry,

It should not be a problem as long as you can access the area just under the condenser from the outside of the trailer. IIRC, the 27 uses a roof vent and not a side vent like the smaller trailers, so you might have to remove the unit.

Another method that I have used with great success on roof vent models is to place a couple of Silenex (very quiet) fans under the screen that is found below the refer's roof shroud. These fans (2) pull the warm air OUT of the venting baffle and accomplish the same purpose as Stu's kit.

It is easy to run a wire down the back of the fridge for the power connection, and if you don't have a thermostat (which most folks don't), I would simply wire it to a switch inside the trailer. These fans are so quiet that you can leave them running continually if you like and you'll never hear them.

Jo Mojo · 10-29-2010, 07:55 AM

Hi Lew,
Thanks for more great info on this fan fix. Question, after reading the instructions on Stu's website, it sounds like his kit is mounted next to the condenser...which is in the upper compartment, no? So will there be room for a second fan up there as well? Or do I have that wrong? I am techinically challenged and will not be installing this myself, but still I want to be clear.

We are headed to the Keys in middle of Nov so anticipate some hot humid days and want to make sure this is handled. Do I order the second fan from Snyder as well? Will it come with all the brackets, etc I need to install?

After re-reading the threads I am wondering if I should have gone with the Silenex...Stu doesn't really talk about noise on his site, just efficiency. Efficiency is great and this problem is all about noise for me! I liked the word 'kit', which is why I went with Snyder as the posts on the Silenex discussed trips to Home Depot and such and that is just not my bag, baby.

Wish you were in GA and could install this for me :-0...let me know what you think about a source for the second fan.

Muchas Gracias

pattonsr · 10-30-2010, 10:29 PM

Lew,

Thanks for the information on a 2011 27FB Classic. If the refrigerator needed to be removed, is that a big deal for a pro like you?

Barry

lewster · 10-31-2010, 07:51 AM

Quote:

Originally Posted by pattonsr

Lew,

Thanks for the information on a 2011 27FB Classic. If the refrigerator needed to be removed, is that a big deal for a pro like you?

Barry

Removing a fridge is normally not a big deal.....except in an Airstream!

I don't know why, but they feel that they have to build the cabinets around the refer units and make it 2-3 times as difficult to remove them. ....... but they WILL come out!

xrvr · 10-31-2010, 12:14 PM

My AS does not have a fridge fan. I asked the dealer to be sure. zz

wbrownrr · 10-31-2010, 03:08 PM

We replaced our noisy fan with a Silenex fan 4 or 5 years ago.... no more noise... adequate cooling in almost all conditions.

aftermath · 11-15-2010, 08:58 PM

OK, I went in today and asked the guys at Airstream about the fan in the fridge. I was told that the coaches with the full size refrigerators that vent through the roof don't have fans unless they were installed as an after market thing.

The smaller fridges that vent out the side of the trailer have fans and some have a switch while others do not. He couldn't figure out why this was the case but he said that that is just how it is.

So, if you have a 25 footer or longer and are confused as I was, don't be. We don't have a fan unless it was added at some later time.

dznf0g · 11-15-2010, 09:06 PM

Quote:

Originally Posted by aftermath

OK, I went in today and asked the guys at Airstream about the fan in the fridge. I was told that the coaches with the full size refrigerators that vent through the roof don't have fans unless they were installed as an after market thing.

The smaller fridges that vent out the side of the trailer have fans and some have a switch while others do not. He couldn't figure out why this was the case but he said that that is just how it is.

So, if you have a 25 footer or longer and are confused as I was, don't be. We don't have a fan unless it was added at some later time.

That is true throughout the industry. Theory is that if there is a straight shot out the roof, natural rise of heat will take care of cooling. If you must exit out the side , that natural rise is interrupted by the restriction of having to change direction. IMHO all refers need a boost of flow to provide adequate cooling of the coils.

Install a cooling fan and be done with it. I started adding fans with my first pop-up in 1984 and never looked back and never have had an unsatisfactory performing refer. My .02$