2 Way Refrigerator Question

[BillKat]

I am a newbie who just purchased a 94 Starcraft PUP.  It has a 2 way frig (12VDC & LP).  According to the wiring diagram in my owner's manual, the refrig will operate via battery when connected to the TV during transportation.  (I currently have an issue with the 12VDC not running lights in the camper etc.  Fuses are good in the converter, runs on shore power... I believe I may have a short in one of the wires...gotta troubleshoot that next weekend.)

MY Question....
I've heard of people running their refrig's on LP during transit, the manual states "Do NOT use LP gas while traveling...danger of fire or explosion if gas line were ruptured in an accident".   It states further that it is illegal in some states to do this.  I'll mainly be traveling in TX, NM, CO, OK & AR.   Who runs their frigs off propane while in transit?   Any other issues I should be aware of.

Thanks,
Craig aka BillKat

[ScoobyDoo]

I don't think it is illegal to drive with propane on except some bridges and tunnels. But that don't make it smart. I'm old enough to remember copper airlines on trucks. What happens when the line cracks and the box gets full of propane? Then you need to stop 3 times to fill the gas tank. (pull into a station with open flame?) When my PUP is moving the tanks will be shut off.

[AustinBoston]

I am a newbie who just purchased a 94 Starcraft PUP.  It has a 2 way frig (12VDC & LP).  According to the wiring diagram in my owner's manual, the refrig will operate via battery when connected to the TV during transportation.  (I currently have an issue with the 12VDC not running lights in the camper etc.  Fuses are good in the converter, runs on shore power... I believe I may have a short in one of the wires...gotta troubleshoot that next weekend.)

MY Question....
I've heard of people running their refrig's on LP during transit, the manual states "Do NOT use LP gas while traveling...danger of fire or explosion if gas line were ruptured in an accident".   It states further that it is illegal in some states to do this.  I'll mainly be traveling in TX, NM, CO, OK & AR.   Who runs their frigs off propane while in transit?   Any other issues I should be aware of.

Thanks,
Craig aka BillKat

This issue comes up from time to time, and the truth is, things have changed somewhat since '94.  The primary change has been with propane tanks.  One of the features of the OFP valves on all new (and, if I recall correctly, all refillable) propane tanks is that they detect and stop excess gas flow from catastrophic leaks.  In other words, the kinds of problems the author of your '94 manual was concerned about are much less likely with today's propane tanks.

Having said that, there are some risks with towing while the fridge is on propane, mostly having to do with gas stations.  Suffice it to say that shutting off the propane before entering the station is very wise.

In some places, you are required to turn off propane at the tank before entering tunnels, and in at least one situation you will not be allowed in the tunnel with a 20-lb propane bottle, on, off or otherwise.

Towing with the fridge on 12V is safer, but has it's own problems.  First, in most setups, it will partly drain your pop-up battery even with a 12V charge line.  Second, using 12V has significantly less cooling than propane, and should only be thought of as a "holding" setting.  Third, if you stop for any length of time and forget to turn off the fridge or disconnect the trailer (3 hours is usually enough), you will return to a dead camper battery AND dead tow vehicle battery.  I can tell you from experience, the moment you turn that key and nothing happens, you will remember the fridge.

For these reasons, more and more people are using propane when towing.  For us, the choice has generally been to only use propane if we are dry camping (we only rarely dry camp) becasue we want every ounce of battery power, even if we don't use it.  

Austin

[tknick]

BillKat, one thing you can do to prevent the fridge from draining your TV's battery when stopped is adding a relay to the 12v charge line coming from your TV.  You install the relay so that the 12v line is only hot when the TV's engine is running, and completely disconnected when the engine is not.  That way, the fridge may completely drain the battery on your camper, but won't drain a drop of juice from the starting battery on your TV.  Once you start the TV again, the relay reconnects and it will start charging the camper battery and running the fridge again.  

Echoing what Austin said, I used to have a 25ft travel trailer.  It had a fridge/freezer that could not run on 12v.  It either ran on propane or 120v AC.  We always ran it on propane when travelling and never had a problem.  That being said, we would always shut it off when refueling.  Our fridge also had a thermocouple that would shut off the propane flow if the flame blew out during transit (in addition to the Over Flow Prevention Device) on the propane tank.

HTH
Travis

[dthurk]

Your subject to this thread indicates you have a 2 way refer.  Is it 2 way or 3 way?  2 way is AC/Propane, and is found in most travel trailers, 5vers and MHs.  3 way is AC/Propane/12 volt and is found in most popups that have refers.  They can use the 3 way as the popup refer is smaller and can run on battery.  The larger units would use way to much battery power to be practical.  

So, if you do have a 2 way as stated, you can't run on 12 volt even if you wanted to.

I do run our TT on propane as we're traveling.  Yes, there are arguments both ways on the issue.  Some bridges and tunnels prohibit propane, on or off.  You have to avoid them.