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Topic: What's with the fridge fans running all the time? (Read 701 times) previous topic - next topic

What's with the fridge fans running all the time?

OK so I get the coach back to storage, turn off fridge, open/defrost, plugged into shore power, but fridge definitely off...keep hearing a little whirring noise, stick my head in & it's the fans (2 small flat ones under the drip tray) constantly on...little wires here & there, all rigged into the fans....looked everywhere for a way to turn off/disconnect...they obviously are running on 12 volt, does this hurt anything for them to keep running all the time, even when fridge is off? I would think they'd burn out a lot faster running all the time?

Re: What's with the fridge fans running all the time?

Reply #1 –
Mine run the same as well. Since the fan needs to run when the door is shut, meaning light is off, it is wired direct to the 12v system. Try the salesman switch. If not, you may have to disconnect at the light.
Peter & Beth Martin
No Forrest? What have you done?
MC# 15890 until Dec 2016; FMCA #F329677
Cincinnati, OH

Re: What's with the fridge fans running all the time?

Reply #2 –
Thanks Peter, messin' with those wires made me a little nervous already....& if I turn off the salesman switch, doesn't that still keep the batteries charged? I'm not leaving anything on, just want the batteries to stay charged.

Re: What's with the fridge fans running all the time?

Reply #3 –
If your coach hasn't been modified your batteries should still charge. The salesman switch just turns off the 12 v power to the house.
Bruce, Linda, and Macy
Zoey RIP 1/20/19
1999 U295 40' build #5400
2017 silver Jeep Wrangler, 1260 watts of solar on top
Moving around the country

Re: What's with the fridge fans running all the time?

Reply #4 –
Maybe a big difference in our coaches, but ours has a rocker switch above the sink with two other lighting rockers. I believe they're called "muffin fans" (no idea why).  As the fan has a hum, I only run ours during the day.
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
Previous: 1983 Airstream 310 turbo diesel, 1979 Airstream 280 turbo diesel
                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
                        DW Judy & Chet the wonder dog
                        Full-Timers 'Sailing the asphalt sea'

Re: What's with the fridge fans running all the time?

Reply #5 –
Very likely the auxiliary fans are NOT OE.  So they will be wired/run according to how the previous owner installed them.

They are a good idea to improve the efficiency  of the absorption refrigerator in high ambient temperatures.  No need to run in cold temperatures.

Most efficient when installed at the top of the cooling fins, exhausting UP.  Access from the roof vent to install them.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: What's with the fridge fans running all the time?

Reply #6 –
There are parasitic loads on both battery banks that cannot be turned.  My Foretravel owners manual says to disconnect the batteries when storing for more than two weeks.  This is one reason why I added solar panels and a voltage sensitive relay to connect both banks together whenever either bank is being charged.
Tom Lang K6PG (originally  KC6UEC)
and Diane Lang
2003 38 U295 build 6209
2016 Jeep Grand Cherokee Summit Ecodiesel
still have tow-ready 2006 Acura MDX 
Temple City, California
Motorcade 16681 California Chapter President
SKP 16663 member of SKP Park of the Sierra, Coarsegold California
FMCA F071251
Retired electrical and electronic engineer

Re: What's with the fridge fans running all the time?

Reply #7 –
Chances are the fans were installed with a thermo switch that is supposed to turn on the fans at a preset temperature, I believe its 120 degrees. When the thermo switch goes bad it can be on or off leaving the fans inoperable or running all of the time. There may also be a switch in the fridge compartment accessible from the outside vent door that turns the fans on and off. I installed two toggle switches on the left wall of the compartment to control the fans.

One other point, according to Valterra their fans were not designed to run full time and they should be installed on top of the fins. Yes I know that is the logical place but the heat produced by the fins will ruin the fan motors prematurely. I installed my new fans, not the Valterra fans, from rvcoolingwarehouse.com just below the fins where it is cooler and they blow cooler air up through the fins. I did this when I installed the new Amish Cooling Unit and had the fridge out of the cabinet. Removing the fridge was not nearly as difficult as I thought it would be. That is with the use of the hydraulic lift table purchased from Harbor Freight.
The selected media item is not currently available.Kent Speers
Locust Grove, OK
1993 U300 SSE 40' (Restored at FOT 2009) Build 4323
720 watts Solar
6V92TA DDEC Silver Engine
2014 Subaru Outback

Re: What's with the fridge fans running all the time?

Reply #8 –
I think there's confusion now as to which fans Miz Dani was referring to in the original post.

I took it to mean the fans on the cooling fins inside the reefer.  The fix for that is to disconnect one of the wires that run to the
interior light.  When you remove the light lens you'll see where the wires are crimped together with a terminal that connects
to the light, then just pull it apart.

Peter & Beth referred to this at the end of Post #1.

Re: What's with the fridge fans running all the time?

Reply #9 –
Quote from: wolfe10 –
They are a good idea to improve the efficiency  of the absorption refrigerator in high ambient temperatures.  No need to run in cold temperatures.
No sense wasting power when not needed, good reason for the switch. My rule of thumb is to run the fans if I know I'm going to run roof air, they work great.
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
Previous: 1983 Airstream 310 turbo diesel, 1979 Airstream 280 turbo diesel
                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
                        DW Judy & Chet the wonder dog
                        Full-Timers 'Sailing the asphalt sea'

Re: What's with the fridge fans running all the time?

Reply #10 –
Quote from: mike leary –
No sense wasting power when not needed, good reason for the switch. My rule of thumb is to run the fans if I know I'm going to run roof air, they work great.

Also, if the sun is shining on that side, you are in and out of the refrigerator a lot-- basically anytime you need to improve refrigerator efficiency.

BTW, strongly suggest this remote sense thermometer from Walmart, etc to monitor refrigerator temps: Acurite Digital Indoor / Outdoor Thermometer 00380 / 00381

Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: What's with the fridge fans running all the time?

Reply #11 –
I would install a switch so that the fans could be used when needed but then switched off when not needed. Should be a simple task to accomplish.
David and Carolyn Osborn
1995 U320C SE 40' Build 4726 Feb 1995
FMCA 147762
Motorcade 17186

Re: What's with the fridge fans running all the time?

Reply #12 –
All fridges should have a switch if muffin fans are installed. Here's ours above the sink.  Being an analog kind of guy, I use this to monitor temps:
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
Previous: 1983 Airstream 310 turbo diesel, 1979 Airstream 280 turbo diesel
                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
                        DW Judy & Chet the wonder dog
                        Full-Timers 'Sailing the asphalt sea'

Re: What's with the fridge fans running all the time?

Reply #13 –
Mike,

The advantage of the remote monitor is that you don't have to open the refrigerator to have a continuous readout of refrigerator temperature.  We have one in the boat, one at home and one in the motorhome refrigerator.  Put it on the dash when driving.
Brett Wolfe
EX: 1993 U240
Moderator, ForeForum 2001-
Moderator Diesel RV Club 2002-
Moderator, FMCA Forum 2009-2020
Chairman FMCA Technical Advisory Committee 2011-2020

Re: What's with the fridge fans running all the time?

Reply #14 –
Quote from: wolfe10 –
Mike,

The advantage of the remote monitor is that you don't have to open the refrigerator to have a continuous readout of refrigerator temperature.  We have one in the boat, one at home and one in the motorhome refrigerator.  Put it on the dash when driving.
I like cold beer, so the fridge gets opened & closed a lot, enough times to keep my eye on the analog.  ;D
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
Previous: 1983 Airstream 310 turbo diesel, 1979 Airstream 280 turbo diesel
                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
                        DW Judy & Chet the wonder dog
                        Full-Timers 'Sailing the asphalt sea'
 

Re: What's with the fridge fans running all the time?

Reply #16 –
Quote from: Traveling Man –
The coldest beer is in the morning then?

Good question, I'll get up earlier tomorrow.  :dance:
1993 U-240 "La Villa Grande"..CAT 3116 w/ Pacbrake PRXB...Allison 3060 6-speed..
Previous: 1983 Airstream 310 turbo diesel, 1979 Airstream 280 turbo diesel
                                      Build # 4297
                                      PNW natives
                      Home base:  'Cactus Hug' (Ajo, Arizona)
                        DW Judy & Chet the wonder dog
                        Full-Timers 'Sailing the asphalt sea'