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DTJ9610
07-22-2011, 06:03 AM
I tried searching for this but couldnt find anything. Has anyone added a fan to their fridge, either outside or inside. Before the keystone I had a Jayco and still visit their site to see what's new. I noticed a thread pertaining to a dual wired fridge fan. Just curious if anyone has installed one on a Keystone. This is the one they listed:

http://cgi.ebay.com/ebaymotors/DOMETIC-NORCOLD-REFRIGERATOR-FAN-RV-12-VOLT-_W0QQcmdZViewItemQQhashZitem3cb9b7c0f9QQitemZ26081 3865209QQptZMotorsQ5fRVQ5fTrailerQ5fCamperQ5fParts Q5fAccessories#ht_10081wt_1167

Festus2
07-22-2011, 06:51 AM
If you check with Camping World, they have a battery-operated (not 12v ---D or other). Haven't heard how effective it is nor how long it will run on a set of batteries.

THedges
07-22-2011, 10:04 AM
On my last 2 TT's I added the outside fan and it made a huge difference. On my current Springdale the fridge gets nice and cold by it self. That is saying a lot here in the AZ desert!

Jim W
07-22-2011, 10:44 AM
I have a battery operated fan in the fridge, from Camping World. This one uses 2 "D" size batteries with a squirrel cage fan .The batteries will last all season from April until Oct. Granted we only go out for 4-5 days a week every month and one long three week trip a season. This seems to work well and moves the air around. I have a thermometer in the fridge and the temps stay's between 30F and 35F on 90F + days.
Jim W

Festus2
07-22-2011, 03:21 PM
Further to what Jim stated in his post above, CW carries two such fans, the "Fridge Aerator" and the "Fridge Cool Fan" priced at $19.30 and $14.00 respectively. Both operate on 2 D cell batteries and claim that you can get 30 days from these. The reviews seemed to favour the Fridge Aerator although there were only 2 such ratings. In any case, the majority of reviewers said that the fridge kept things cooler for longer periods and ran more efficiently. Seems like a pretty good investment if you are camped out in the heat and your fridge is working hard to keep things cold.

jje1960
07-23-2011, 02:30 AM
If you check with Camping World, they have a battery-operated (not 12v ---D or other). Haven't heard how effective it is nor how long it will run on a set of batteries.
I've been using one of the DD fans inside for a few years, they work awesome. The fridge cools down lot's faster and stays without any frost buildup on the fins. As for how long the Batt's last.... unbelievable.... depending on how often it's used obviously... however we only change them like once in the entire season. Ours is a small blue box, will look to see if I can find it again and post link.

Rick
07-25-2011, 07:27 PM
Hi!
I just bought a 19' Springdale, and have been doing mods to it recently. I have the small 2D battery interior fan. It doesn't turn too fast or move too much air, but I guess it's better than nothing. I did install an outside fan in the reefer compartment. I don't know if I'll need it, but old habits die hard. I had one in my previous truck camper (a 1969 Colt), but it was super loud and the fridge needed all the help it could get.

For this mod I used parts I had lying around the garage. I had an old computer and I removed the fan from the power supply. It's 12V, .25Amps. It's smaller than the fan for the CPU, but moved more air at a lower amperage than the larger one. If you do decide to use this fan, be careful as there's capacitors within the power supply that can give you a nasty zap! I cut a small piece of scrap wood and screwed it to the floor of the reefer compartment. I wanted to keep the noise level down (not that there was much) so I insulated the fan from the floor with cardboard (this will be changed to something more durable in the future). Mounted one end of the fan to the scrap wood, with the other end resting on the reefer floor (those short screws were used in the power supply to attach the fan. I used them as short legs). The fan points towards the condenser. Installed a switch I had on the compartment cover so I have access from the outside. I ground down a washer on three sides so it would be square and installed the switch into it. Washer was glued in place on the cover. Put a plug in so I could disconnect the switch wiring and completely remove the cover. Wired in a fuse (Using a 3A that I have on hand, but have to get something smaller). Tapped the 12V off the refrigerator supply. Electrically, it works great. If I ever feel the fridge isn't getting cold enough, I flip the switch. Thought about adding a LED, but didn't want to draw attention to the switch and curious fingers.

Outside switch
http://www.keystoneforums.com/attachments/photobucket/img_17112_0_f8a00cd77fa1aec8e6ab45b26a1ff108.jpg

Switch glued in place
http://www.keystoneforums.com/attachments/photobucket/img_17112_1_138290e371ee00a6a524052f1ff8e215.jpg

Plug for switch disconnect
http://www.keystoneforums.com/attachments/photobucket/img_17112_2_55b5f47318f4770dc846991878e77066.jpg

12V tap off refrigerator supply, fuse, and fan
http://www.keystoneforums.com/attachments/photobucket/img_17112_3_61d723e4fef6cb1c76010c89adb11703.jpg

My problem is that my refrigerator may get too cold! The freezer section works fine. I've only turned it on once, and using a wireless temp gauge, the reefer section got down to freezing during a hot day. I'll have to play with the thermistor slide and see if I can adjust the temp. If not, I may get one of these-
Thermistor Repair Kit (http://www.snip-the-tip.com/cgi-bin/articca.cgi)

These mods are great!! I love the ideas from everyone.

Rick

Paddler
07-26-2011, 04:32 AM
Nice job! Thanks for posting the pictures along with the commentary, they answered a couple questions I had in reading the text.

geo
07-26-2011, 05:21 AM
Rick -

Just to clarify, you have the fan mounted at the base of the fridge blowing air up towards the condenser, correct? Does this affect the fridge when running on gas? I understood that these fans should be installed at the top of the condenser chimney (pulling air away from the condenser), but does it really make any difference?

BTW, that's a very common 12v fan used in electronics called a "muffin fan". They are fairly cheap and are easy to buy new off the shelf for just a few bucks. Saves getting zapped by the power supply capacitor if you don't discharge it. Look at Amazon, Altex, Fry's, or any electronics parts store.

Ron

hsmunoz
07-26-2011, 07:37 AM
I installed one of these fans from the OP's link. They are all over the web for ~14 bucks. I did notice a small improvement in overall cooling of my fridge. I am happy with this easy mod.

Used on both a Dometic and Norcold and both work fine. Just tap the hot line on the fridge light.

vwalla
07-26-2011, 08:03 AM
I am sort of confused (but that is easy according to my DW:)). Is it better to place a fan inside on the coils or on the outside?

Rick
07-26-2011, 04:16 PM
Geo-
Q. "Just to clarify, you have the fan mounted at the base of the fridge blowing air up towards the condenser, correct?"
A. Yes, it's pointing towards the condenser. As you can see in the photo, there's no room under the chimney to place it. There's all sorts of flame guards to (I'm guessing as one idea) protect the flame from blowing out.
http://www.keystoneforums.com/attachments/photobucket/img_17175_0_14c28181dd9a24cceae92cd2278461be.jpg

Q. "Does this affect the fridge when running on gas?"
A. Don't know...only had the fridge on once to make sure it worked.

Q. "I understood that these fans should be installed at the top of the condenser chimney (pulling air away from the condenser), but does it really make any difference?"
A. Don't really know...lots of theories and discussion on that topic. I just feel that if the fridge isn't running as cold as you'd like, add some type of outside fan.

To clarify, I have the Dometic DM2652. I was looking in the Dometic installation manual about fans, and found some info. There is an optional fan from Dometic. Fan #8 is for 8 different refrigerator models, and fan #9 is for 10 different models (mine would take a #9).
http://www.keystoneforums.com/attachments/photobucket/img_17175_1_07cab62d6ac1800374c76da350d6e33e.jpg

There's two types of venting - Roof venting (such as I have)
http://www.keystoneforums.com/attachments/photobucket/img_17175_2_425c4a0a0e13b5a2378aac988748bc18.jpg

and side venting (where you only have an upper and lower side vents).
http://www.keystoneforums.com/attachments/photobucket/img_17175_3_dd6bc2080b4d26ec8b381606b335ba52.jpg

As you can see, Dometic makes no mention of use of a fan for a roof vent installation. Only when the fridge has side vents is a fan mentioned. Who knows where they install it (*Fan(s) position may vary by model - That's a lot of help). Maybe someone who has a side vent installation can tell us.

The rest of this is listed in the next post since only 4 pics per post is allowed...

Rick
07-26-2011, 04:28 PM
This pic is looking from the chimney bottom up. The chimney is 31" long.
http://www.keystoneforums.com/attachments/photobucket/img_17176_0_8aab4d7a3f0b9a9a469d68232a3e8a16.jpg

When it cools down this evening or tomorrow morning I'll try to get a look above the chimney.

I'm thinking of getting the inside fan and wiring to the lite switch such as hsmunoz writes.

vwalla-
"Q. Is it better to place a fan inside on the coils or on the outside?"
A. Yes. Someone correct me if I'm wrong, but you're trying to accomplish two different things. The inside fan will move the air inside the fridge making for a shorter cooldown period and more even cooling. The fan in DTJ9610's link is just attached to the fins and is high powered. You can purchase free standing fans that use 2 D batteries like this (I have the blue type...it's 20 years old, and doesn't move too much air).
http://www.keystoneforums.com/attachments/photobucket/img_17176_1_b991c57b7945e7411bcb9a3d185088d3.jpg
http://www.keystoneforums.com/attachments/photobucket/img_17176_2_77e574d0fc58c45093a33a15bd41bcd2.jpg

The fan mounted outside is to help remove hot air from the reefer compartment (condenser, chimney) which helps to make the refrigerator more efficient.

Do a search for "outside rv refrigerator fan" and there will be quite a few links with everyone's opinions and fans for sale.

Here's a couple of quotes I found, and take them with a grain of salt-
To assist with air circulation you can purchase an inexpensive, battery operated refrigerator fan. Put the batteries in and place the fan in the front of the refrigerator compartment blowing up. Cold air drops and warm air rises. The fan will improve the efficiency by circulating the air and it will reduce the initial cool down time by 50%.

And

Another good idea is to install a 12 volt, thermostatically controlled refrigerator vent fan at the back of the refrigerator, or at the top of the roof vent, to assist with drafting the hot air away from the refrigerator. If you are mechanically inclined these fans are fairly easy to install, or you can have your RV dealer install one for you. Either way it’s worth it. The fan removes the heat built up behind the refrigerator improving the refrigerators performance by up to 40%.

That's enough from me for now!

Rick

vwalla
07-26-2011, 04:56 PM
Thank you for the detailed information. Very informative and greatly appreciated!

V

Rick
07-26-2011, 07:30 PM
Last post from me!
I went on the roof of the trailer, and this is my vent cover.
http://www.keystoneforums.com/attachments/photobucket/img_17188_0_0cdea5b7d4b89260b1dfa0d4d31b8aa2.jpg

Took that off and this is what greeted me (I placed the CPU fan there for sizing only). The wire mesh is about 6.5" X 20"-
http://www.keystoneforums.com/attachments/photobucket/img_17188_1_0934fc2bf4f20f74f567afcea058a09c.jpg

Well, I can't get below the wire mesh without removing the vent cover housing, and I don't want to do that. Looking inside, this is what I saw-
http://www.keystoneforums.com/attachments/photobucket/img_17188_2_e4dfaf64e183e4e1edc74d52396f0e2f.jpg
There's a cover over the chimney! So no chimney fan for me. I have room for only the 1 fan at the bottom. I could place a bank of fans on the top...If I decide I have cooling problems, that'll be my next mod. Have fun with this!

Rick

jol
08-09-2011, 03:11 AM
Not sure who or when but I have a 2004 Sprinter purchased used and the kitchen is on a slide when they did the recall fix on it the repair person said that it had a fan on it and that it was controlled by a thermostat. I know on a pop-up we had I did come up with a 12 volt muffin fan and a piece of sheet metal to seperate the top from the bottom as the refrigerator would not really cool when it got above 90 degrees, that was a Dometic 3 way running on propane or 120 volts, I do not think the 12 volt ever really did a good job so never really used it. That said the fan did help a lot but not sure if the sheet metal that was installed didn't help tons also.

JRTJH
08-09-2011, 10:36 AM
We have a 2011 Springdale fifth wheel with a top vent on the refer. The refer is a Dometic RM2652. There is a factory installed muffin fan between the bottom coils and the freezer coil (outside the refer). This has a 3amp fuse on it and there is a thermistor to turn the fan off and on. On the first refer we had, the fan ran all the time and never turned off. The refer did not cool properly. Dometic replaced the entire cooling unit and it now works great. The fan now turns on when it's about 95 or so and cycles off and on depending on the temp at or around the top of the lower cooling fins. It only runs about 3 or 4 minutes at a time and is off for over an hour before coming back on.

From what little I know about evaporative cooling, the refer enclosure is constructed (much like a fireplace) to cause hot air to rise in a controlled space creating a current of air which pulls cool air in the lower vent and exhausts the warmer air out the top vent. This conduction of air passes over the fins capturing heat and replacing it with cooler flowing air.

I understand that the Dometic fan accessory kit can be installed on most Dometic models, and is pretty much what the mods above have accomplished. Dometic wants over $60 for the kit, the only advantage I see is the thermistor to control the fan so it doesn't run 24/7.

The fan enhances the conduction of air causing more cool air to come in the bottom vent and exit the top vent.

As for an inside fan. If you have "hot spots" or "cold spots" in your referigerator, if you experience food freezing in the referigerator, then a battery operated referigerator fan will help even the temperature throughout the inside of the referigerator, There is usually no need to have a fan in the referigerator or in the freezer if the unit is operating properly.

A home referigerator has one (or more) fans in the referigerator to help even the temperatures, and usually one in the freezer to blow freezing air over a certain surface to "supercool" foods. This is not an option in absorption referigerators under 10 cu ft. and hasn't been needed on any referigerator we've used.