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Camplite => Camplite General Q & A => Topic started by: nmken on May 22, 2015, 01:42:10 PM

Title: Refrigerator Power Priority - AC/12V/LP?
Post by: nmken on May 22, 2015, 01:42:10 PM
All:

I'm wondering about how to best power my refrigerator during travel.  I've been using 12V and note that on some days it can warm up quite a bit.  I had read once in an unreliable forum that LP provides greater cooling than 12V and am wondering if anyone can confirm or debunk this notion?  Currently I save LP Power for campgrounds that have no services.

Thanks
Ken
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: shovelhead on May 22, 2015, 01:48:52 PM
Ken I've left mine on "Auto" which about 99% of the time is LP even when I'm on shore power. I've had issues with shore power having brownouts. This causes my fridge to go into a error condition "E0"
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: david on May 22, 2015, 03:20:46 PM
I once saw wattage figures quoted for an RV refrigerator on 12V DC vs 120V AC. The 120V AC was three times higher. So that seems to confirm that AC will cool faster. And I also think that LPG will cool faster still but not as great a change as DC to AC.

But since I never camp where 120V AC is available (well so far) I leave the fridge on LPG all of the time when we travel.

David
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: charliem on May 22, 2015, 04:05:30 PM
[font size="3"]Ken,

From my experience and calculations the priority should be propane, 120V if available, 12V never.  The 12 volt option is really a hangover from times past where folks worried about safety on the road. Today's LP bottles come with flow rate limiters that essentially shut off if a line is broken. The larger fridges, such as in the 21s, don't even offer a DC mode. I leave mine on auto which uses propane on the road. When 120V is available the fridge switches to AC, but switches back to propane in the event the CG 120V goes down.  For my 7 cu ft fridge the cooling is approximately the same for gas or 120V.

Some of the smaller fridges offer a 12V option, but my numbers and experience indicate the DC mode is far less effective than either of the other two. And it will suck a battery dead before you can even get the brew bottle open. Running the fridge on DC while traveling will essentially eliminate battery recharging, and my even yield a negative charge rate. As I said: 12 volt never.
[/font]
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: pinstriper on May 22, 2015, 11:18:17 PM
I'm gonna say this about never using DC: "Bah!"

I still leave the propane off while in transit because I don't trust the switches to keep the furnace off, and us (well, not ME) to be sure we (again...not ME) didn't leave the hot water heater on.

I turn the fridge on AC the evening before we load for a trip, or at latest morning of the evening transit, and we camp with hookups. So the battery is fully charged when we leave. I'm not depending on the ride to recharge the battery. The fridge on DC is just to keep it cold. So pretty much I'm not running the fridge off the battery, but off the alternator.

Now, for those who boondock/dry camp, I retract my first statement.
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: swbc150 on May 23, 2015, 12:46:09 AM
I've been rving for over 20 years. I always precool the frig here at the home before I leave on the house current. When I pull away from the curb the Frig is on LP and stays on LP till I get back home. LP cools the best and as said before no worries when traveling and 12V is the worst option they ever offered on these RV Frigs.
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: whoofit on May 23, 2015, 08:18:25 AM
My TV does recharge the battery while running the fridge on DC just fine. To the tune of 30% in 1:45 of highway driving. Not sure why but there you have it. We always travel in DC mode. Like Pin, we start with cool food to begin with... with only 2 x20 lp tanks it's worth the conservation effort we feel. And who really knows for sure how much lp is left in the tank to begin with? Unless you have an auto changeover, and it works. But we are simple folk.
 
We really like or DC option. Can you tell?
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: mitch on May 23, 2015, 09:33:37 AM
For those that leave it on LP during travel, is there any concern with the flame blowing out because of wind?  I kind of just assumed that the flame would blow out and the ignitor would just be working extra hard to try to relight it.
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: david on May 23, 2015, 10:10:48 AM
The one time I travelled several hundred miles with the propane on and the fridge burner lit, the pilot did not blow out. Even if it did the igniter system would try once and if it didn't light it would trip out.

I think that there is little chance of the main burner blowing out underway. Maybe a greater chance of the pilot blowing out. But if it did then when we stopped we would see the error light, then we would reset and relight the pilot. All with little temperature loss inside the fridge.

David
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: ctmark on May 23, 2015, 05:19:04 PM
When we first got our trailer, we drove for 4 hours with the frig on 12V and had a nearly dead battery when we got to our campsite.  We took the trailer in for service after we got back to get the wiring checked and all was ok.  We may not have adequate wiring from the tow vehicle to the trailer battery to keep the battery charged.  
Since then, we always use propane on the road and it works great!
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: swbc150 on May 23, 2015, 06:13:24 PM
No issues ever with a blow out pilot light. It is well protected, no need to worry about it. I have driven through 50+mph winds on the highway and the Frig was still running fine when I stop for a break or for the day.
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: swbc150 on May 23, 2015, 06:21:20 PM
One of the ways I conserve my Propane is Not to leave the Hot Water Tank on all of the time once I get to the Campsite. Once I know I need hot Water I then turn it on ahead of time, like for dish washing or a shower, then off it goes.
Running the Frig on Propane once I leave my Home and then back home has never seen allot of use of the propane and once at the campsite will dictate to the amount of the cooling you need with the Frig setting.
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: whoofit on May 26, 2015, 09:32:56 AM
[p]So we did DC on the fridge again with our 2:45 trip home yesterday with a much different result than before. This time we only saw a 10% rise in SOC. While wondering what went wrong this time I heard a faint humming sound, actually felt the vibration first. I left the water pump on with a completely dry fresh water tank. It must have been on the entire trip....Doh![/p][p]
[/p][p]Can't work up the courage to see if the pump still pumps.[/p][p]
[/p][p]Also figured I'd add that our experience has been under mild ambient temps. The duty cycle is probably lower than it would be in the heat of the summer. LP may be the only way then. It'll be fun to find out.[/p]
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: shovelhead on May 26, 2015, 10:11:50 AM
My 2014 cl21rbs is LP or 120vAC no DC option
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: nmken on May 26, 2015, 10:44:10 AM
The way I'm leaning is that to travel with 12v as long as the refrigerator is maintaining temp and switching to propane only if I need to catch up.  There is much speculation on the web about laws about propane but from what I read, it is legal everywhere unless specifically called out and even then the restrictions (ie for tunnels) are for propane loads much larger than a 2 20 lb bottle set up.  I've seen comments about not having igniters enabled at gas stations but haven't found any actual laws to cover this - can anyone come up with anything beyond opinion on that matter?
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: whoofit on May 26, 2015, 10:48:26 AM
[quote source="/post/11399/thread" timestamp="1432647850" author="@nmken"]The way I'm leaning is that to travel with 12v as long as the refrigerator is maintaining temp and switching to propane only if I need to catch up.  There is much speculation on the web about laws about propane but from what I read, it is legal everywhere unless specifically called out and even then the restrictions (ie for tunnels) are for propane loads much larger than a 2 20 lb bottle set up.  I've seen comments about not having igniters enabled at gas stations but haven't found any actual laws to cover this - can anyone come up with anything beyond opinion on that matter?[/quote]In our area it is expressly prohibited to have more than ONE 20lb propane tank on your property without special permitting. Ain't that a kick in the pants....
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: charliem on May 26, 2015, 11:15:20 AM
[quote source="/post/11400/thread" timestamp="1432648106" author="@whoofit"]In our area it is expressly prohibited to have more than ONE 20lb propane tank on your property without special permitting. Ain't that a kick in the pants....
[/quote][font size="3"]Exhibit one in my avoidance of home owners associations. Does Chairman Mao head up your local People's Republic of Suburbia?
[/font]
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: whoofit on May 26, 2015, 12:36:26 PM
Quote from: @charliem" timestamp="1432649720" source="/post/11405/thread[quote source="/post/11400/thread" author="@whoofit" timestamp="1432648106"]In our area it is expressly prohibited to have more than ONE 20lb propane tank on your property without special permitting. Ain't that a kick in the pants....
[font size="3"]Exhibit one in my avoidance of home owners associations. Does Chairman Mao head up your local People's Republic of Suburbia?
[/font][/quote][p]Why yes, Comrade. Actually a bunch of little "Fearless Leaders". Needless to say the Yankee in me forces me to be, how you say it in English, a bit dissenting?[/p][p]
[/p][p]It is the whole town too...
[/p]
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: mitch on May 26, 2015, 12:47:40 PM
I believe it was Groucho Marx (not Karl) who said, and I'm paraphrasing, "I'd never want to be a member of a club that would have me as a member". Same goes for HOA's
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: charliem on May 26, 2015, 05:42:57 PM
[quote source="/post/11414/thread" author="@whoofit" timestamp="1432654586"][quote source="/post/11405/thread" author="@charliem" timestamp="1432649720"][font size="3"]Exhibit one in my avoidance of home owners associations. Does Chairman Mao head up your local People's Republic of Suburbia?
[/font][/quote][p]Why yes, Comrade. Actually a bunch of little "Fearless Leaders". Needless to say the Yankee in me forces me to be, how you say it in English, a bit dissenting?[/p][p]
[/p][p]It is the whole town too...
[/p][/quote][font size="3"]Wonder what's the equivalent of "Sieg Heil! in North Korea?
[/font]
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: maryvanilla on May 27, 2015, 11:23:16 PM
I just picked up my new 21BHS and cool fridge with food running on propane blew out with 30 mph cross wind on I-90. Found after freezer defrosted and contents warm. Hot day outside and it was about 4 hrs between me checking fridge. Moral of the story, strong crosswinds blowing into your fridge vents can knock your propane cooling out on the road. Cycled on/off at rest stop and got it fired back up. The next day i got stuck in Mitchell, SD with 40-50 mph crosswinds. Decided to camp pointed into the wind...
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: whoofit on May 28, 2015, 10:31:57 AM
[quote source="/post/11455/thread" timestamp="1432672977" author="@charliem"]
Quote from: @whoofit" timestamp="1432654586" source="/post/11414/thread[p]Why yes, Comrade. Actually a bunch of little "Fearless Leaders". Needless to say the Yankee in me forces me to be, how you say it in English, a bit dissenting?[/p][p]
[/p][p]It is the whole town too...
[/p]
[font size="3"]Wonder what's the equivalent of "Sieg Heil! in North Korea?
[/font][/quote][p]I dunno, Charlie. Probably safe to do what the next guy is doing though.[/p][p]
[/p][p]If politics has taught me one thing it is this. Sorry, feeling a tad bit Nitty, Gritty and Dirty today. Remember them?[/p][p]
[/p][p]
[img style="" style="max-width:100%;" src="http://i1312.photobucket.com/albums/t521/minuteman1965/11196329_10153272185662726_4296328838781146811_n_zpsz64p4ugh.png"]
[/p]
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: whoofit on May 28, 2015, 10:43:48 AM
[quote source="/post/11595/thread" author="@boondockler" timestamp="1432779796"]I just picked up my new 21BHS and cool fridge with food running on propane blew out with 30 mph cross wind on I-90. Found after freezer defrosted and contents warm. Hot day outside and it was about 4 hrs between me checking fridge. Moral of the story, strong crosswinds blowing into your fridge vents can knock your propane cooling out on the road. Cycled on/off at rest stop and got it fired back up. The next day i got stuck in Mitchell, SD with 40-50 mph crosswinds. Decided to camp pointed into the wind...[/quote]Well, that did suck. Did your dealer offer any advice?
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: shovelhead on May 28, 2015, 03:59:41 PM
[quote source="/post/11405/thread" timestamp="1432649720" author="@charliem"][quote timestamp="1432648106" author="@whoofit" source="/post/11400/thread"]In our area it is expressly prohibited to have more than ONE 20lb propane tank on your property without special permitting. Ain't that a kick in the pants....
[/quote][font size="3"]Exhibit one in my avoidance of home owners associations. Does Chairman Mao head up your local People's Republic of Suburbia?
[/font][/quote]How "progressive"  TIC
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: whoofit on May 28, 2015, 04:51:18 PM
[quote source="/post/11647/thread" timestamp="1432839581" author="@shovelhead"][quote source="/post/11405/thread" timestamp="1432649720" author="@charliem"][font size="3"]Exhibit one in my avoidance of home owners associations. Does Chairman Mao head up your local People's Republic of Suburbia?
[/font][/quote]How "progressive"  TIC
[/quote][p]It is one of the most conservative towns in my state too.[/p][p]
[/p][p]Now, picture me fighting this. I go to the Hall of Shame and ask for a waiver or repeal. They stand upon their conservative principles and say "You can do more with less, whoofit. Try to be more conservative." I argue, "But I need 2 tanks for my RV, massa!" They reply, "We will not allow such liberal amounts of propane to be stored without permit."[/p][p]
[/p][p]How do you fight it? Ignore it.. "Viva la Resistance!" or sumthin' like that. More like hide them in a tank cover...
[/p]
Title: Refrigerator Power Priority - AC/12V/LP?
Post by: scout on June 08, 2015, 04:51:47 PM
nmken,

Our mini fridge is likely different than your 16 TBS, but like many others, I pre cool the night before. (I find my beers are cooler with LP rather than 12v). I keep the fridge on during transit, but turn it off when fuelling, and when travelling on the ferry system in British Columbia. Technically it would be considered an open flame
 
...the ferry terminals require you to shut off your propane prior to boarding anyway, and most gas stations up here have the "no open flame/spark policy" stickers on the pumps or close by. As a full time hose jockey I have been to a few gas station incidents involving open flame and gasoline vapours... :-/

I have had the pilot light blow out a few times, but the auto shut off stops the flow until I catch it at the next road side stop...I agree the 12v adds a lot of heat to the underside of the fridge...you can feel the heat radiating through the vent on hot days when passing close by.