3-way refrigerator - How to use it

Discussion in 'Refrigerators and Coolers' started by tnchuck100, Sep 10, 2008.

  1. tnchuck100

    tnchuck100 New Member

    574
    1
    Feb 8, 2007
    There have been many questions about the operation of these refrigerators. I have posted this as a comment on another thread but I thought it warranted its own topic.

    It is amazing how many different thoughts are out there about how 3 way refrigerators work. Most seem to be the result of following advice by others rather that actual experience. Here I will mix theory and experience.

    First, we will assume the refrigerator is not defective in some way. It should make no difference which heat source is used. It's just heat. Be it one of the 115 watt (110V or 12V) electric heaters or a propane flame. It's just heat.

    Second, the refrigerator must be level to operate efficiently. If it is not level the liquid in the system can pool and restrict or even block circulation. Damage to the system can result if operated off level for an extended period of time. While traveling level does not matter because the liquids are "sloshing around" and do not get a chance to pool.

    Next, The units do take time to cool when started. The normal rate of cooling is about 3 - 6 degrees per hour. Ambient temperature and having a fan to blow air across the condenser fins will affect this rate. I start the cooling about 18 hours before leaving. Also, the food placed in the refrigerator should be cold already.

    Now, when to use which heat source and why.

    110V - use this whenever it is available. The thermostat will control the temperature.

    12V - use this when traveling. There is no thermostatic control. It is possible to freeze things. If you are traveling less than 6 hours it should not be a problem. If you stop for less than 1 hour you should not have any battery problems. If more than an hour switch to propane.

    Propane - use when 110V is not available (dry camping). Normally it should be set to HIGH. Adjusted to MED or LOW if it gets too cold. There is also no thermostatic control in this mode. Contrary to what is generally said there is no "pilot light". It is just a constant flame. The refrigerator uses very little propane.

    You may have seen the sticker that tells you to use only one heat source at a time. The system has been designed to use a specific amount of heat to produce the heat exchange cycle. Increasing the amount of heat will not lower the refrigerator temperature. In the case of the propane you are decreasing the amount of heat (MED and LOW) to increase the refrigerator temperature if needed since there is no thermostat control.

    To monitor the temperature in the refrigerator I use a wireless indoor/outdoor electronic thermometer. (Acurite, About $10-$15 at Wal-Mart)

    It hope this clears up some mis-information on the operation of these refrigerators.

    <font color=blue>Chuck & Mary - Sparta, Tennessee
    '00 Dodge Dakota <img src=../Images/icons/icon_smile_suv.gif border=0 align=middle alt="Tow Vehicle"> '08 Flagstaff Micro Lite 18FBR
    '03 Harley Davidson Ultra Classic <img src=../Images/icons/icon_smile_bike.gif border=0 align=middle alt="Bicycle"> '04 Timeout <img src=../Images/icons/icon_smile_pu.gif border=0 align=middle alt="PopUp"></font id=blue>
     
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  2. LynnAllen02

    LynnAllen02 Active Member

    1,102
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    Apr 26, 2006
    Long Island, New York
    Chuck:

    You ought to turn this into and submit as an article!

    Lynn

    2006 Pony 283*2008 Liberty* Reserved 2008: 16 days Camped: 11 nights
     
  3. theseus

    theseus Centerville, OH

    1,956
    67
    Feb 6, 2007
    Centerville, OH
    Nicely stated! I agree with Lynn - This should be a sticky topic in the refrigerator section...

    ______________
    2004 Expedition & 2000 Palomino Mustang SL-SG-FT
    http://www.thecampingchild.com

    Edited by - theseus on September 10 2008 09:27:21
     
  4. Luv2ridebikes

    Luv2ridebikes New Member

    1,949
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    Apr 17, 2005
    Granger, IN
    Thanks Chuck - I remember reading your post on this subject and it certainly improved my understanding of the topic.

    Steve & Deb (boys are grown & gone)
    Aspen & Riley (the 4 legged children)
    05 Fleetwood Sequoia & lot's of bikes! <img src=../Images/icons/icon_smile_bike.gif border=0 align=middle alt="Bicycle"><img src=../Images/icons/icon_smile_bike.gif border=0 align=middle alt="Bicycle">
     
  5. jushavnfun

    jushavnfun New Member

    76
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    Nov 21, 2007
    Chuck,
    Thanks...This is my next project along with the heater to be tackled on the camper rebuild/overhaul. I have the repair manual from Starcraft, but it covers how to R&R, not diagnose and service.

    Marty & Elizabeth
    Proud owners of our vintage PUP, "Riff Raff"

    To ALL who have, or are serving... Thank You and Welcome Home!
     
  6. Retired Alex

    Retired Alex New Member

    1,124
    1
    Oct 2, 2003
    Limoges, Ontario
    For a detailed description of how RV fridges work check this site. http://www.rvmobile.com/tech/Trouble/cooldoc.htm

    For detailed testing procedures on various units go here http://www.gasrefrigeration.net/dometic_manuals.htm
    The link goes to Dometic but there is a link at teh top to Norcold.

    Alex & Mary Burnett
    06 Trail Cruiser 26QBS, 2006 F-150 XLT
    http://users.xplornet.com/~burnetta

    Edited by - Retired Alex on September 14 2008 00:05:45
     
  7. Fiveofun

    Fiveofun Member

    58
    0
    Sep 15, 2008
    Las Vegas, NV
    So from this post, I take it if the PUP is pluged into an outlet at home, the fridge will cool down? I just want to verify.

    2005 Jeep Grand Cherokee
    Looking for some kind of off road PUP
     
  8. tnchuck100

    tnchuck100 New Member

    574
    1
    Feb 8, 2007
    Yes. As long as the 110V switch on the refrigerator is turned on (the green one).

    <font color=blue>Chuck & Mary - Sparta, Tennessee
    '02 Chevy Suburban <img src=../Images/icons/icon_smile_suv.gif border=0 align=middle alt="Tow Vehicle"> '08 Flagstaff Micro Lite 18FBR
    '03 Harley Davidson Ultra Classic <img src=../Images/icons/icon_smile_bike.gif border=0 align=middle alt="Bicycle"> '04 Timeout <img src=../Images/icons/icon_smile_pu.gif border=0 align=middle alt="PopUp"></font id=blue>
     
  9. Fiveofun

    Fiveofun Member

    58
    0
    Sep 15, 2008
    Las Vegas, NV
    Thanks for the reply. Sorry, can I clarify one more thing, this will work with the PUP closed, correct?

    2005 Jeep Grand Cherokee
    Looking for some kind of off road PUP
     
  10. tnchuck100

    tnchuck100 New Member

    574
    1
    Feb 8, 2007
    Yes. The refrigerator will operate while the PUP is open or closed. Just be sure it is pretty close to level.

    <font color=blue>Chuck & Mary - Sparta, Tennessee
    '02 Chevy Suburban <img src=../Images/icons/icon_smile_suv.gif border=0 align=middle alt="Tow Vehicle"> '08 Flagstaff Micro Lite 18FBR
    '03 Harley Davidson Ultra Classic <img src=../Images/icons/icon_smile_bike.gif border=0 align=middle alt="Bicycle"> '04 Timeout <img src=../Images/icons/icon_smile_pu.gif border=0 align=middle alt="PopUp"></font id=blue>
     
  11. MovingRightAlong

    MovingRightAlong New Member

    219
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    Aug 28, 2008
    Salem, NH
    This may be a foolish question, but are you talking about the switch in the back that allows you to switch from DC/AC/Propane?

    Is there another switch I should be looking for?
     
  12. LynnAllen02

    LynnAllen02 Active Member

    1,102
    0
    Apr 26, 2006
    Long Island, New York
    Nope that's the switch.

    We pop up, close the frig door, plug into our house current the two nights before we leave, pop pup down.

    Next night pop up, load frig with cold food, and frozen meals, forzen waters. Pop down, keep connected to house current.

    AM when we leave, disconnect from house current, turn off frig, do not forget to close frig vent (don't want to say why I know you should not forget this) drive 6-7 hours, we do not use battery power, I save battery for the campground.

    Popup, turn on propane switch after leveling pup. We monitor temp throughout he trip, day time when its hot it gets warm, need high, night time when it gets cool, need medium! As my frozen stuff thaws and I use things up, I replace with things from cooler to keep it full, works better

    Love my frig

    Lynn
     
  13. NHDalton

    NHDalton I camp, therefore I am

    237
    0
    Jun 30, 2008
    Ayuh, New Hampsha
    Something crosses your mind and you come to the Pop Up Portal to find your answer. Thank you Chuck. Appreciate it.

    I am going boondocking for 4 days coming up and have other such trips planned after that too. This information helps.
     
  14. MovingRightAlong

    MovingRightAlong New Member

    219
    0
    Aug 28, 2008
    Salem, NH
    Another dumb question, I had my fridge plugged in for two days. The metal shelves were cold so it was definitely working, but it wasn't as cold as I expected, while it seemed to work better at the campground last summer.

    I had it plugged in through a basic extension cord to my house, will it work better when I get a full 30V running?
     
  15. suprz

    suprz may you never doubt yourself....

    1,404
    0
    Feb 1, 2007
    no, it wont make a difference if you were plugged into a 30 Amp service, it is still 120 volts. these fridges are only good to around a 40 degree difference between the ambient outside temperature and the inside temp of the fridge, Also, something to remember is that the sun hitting the side of the PUP may also have a bearing on the temp and the cooling effeciency of the fridge. The venting on the fridges for these PUPs if poor to say the least. that is why so many of us have put on baffles and cooling fans in the space where the vents are to promote good venting of the hot exhaust from the cooling fins behind the fridge. you can do a search on this topic and find alot of threads about them
     
  16. Somehow or another, I missed this thread the first time around. Very good information, Chuck. I just made it an article.
     
  17. Dredwolf

    Dredwolf New Member

    101
    0
    Apr 13, 2008
    Moore, SC
    [:D] Great info!

    And yes, I have been absent for some time, just got back from a week of camping with the PUP at Desoto Park in St. Pete, Fla....had trouble with the 3-way propane staying lit, so doing some research before starting the troubleshooting process.
     
  18. offline246

    offline246 New Member

    16
    0
    May 11, 2009
    Where/what is the frig vent? I've never heard of that.
     
  19. On the outside of your camper behind the fridge will be 2 vents. The bottom one is an access door that lets you choose the power source and light it (if on gas). Above that will be a fixed vent panel where the heat escapes from the fridge. That is the vent.
     
  20. Daduv3Boys

    Daduv3Boys American by birth, Southern by the Grace of God!

    299
    0
    May 25, 2009
    Harvest, AL
    This is some very good info. Thanks a ton, Joe and Chuck.
     

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