EPDM Coatings
rvupgradestore.com Composet Products Custom Yacht Interiors

Author Topic: Propane! ... new full-timer ;)  (Read 13584 times)

RoverGirl

  • Posts: 2
Propane! ... new full-timer ;)
« on: March 24, 2005, 12:43:32 PM »
hi All!
I'm new to this board ... and new to full-timing as well, but that's what i'm up to!
I've been out now for just 7 days, dry-camping the whole time so far ...
I don't think that my propane tanks have a proper working gauge on them ... so i'm getting pretty close
to thinking i'd better go get them filled again (this will be the first time).  I've been running my refrigerator full-time
with the propane tanks on while i drive.  One question -- is this a no no?  I need my fridge to run while i drive so I don't
see that turning the tanks off is an option!  Any thoughts? 
I've done some minimal cooking with the stove -- heating up water for coffee; a big juicy steak one night; chille; chicken breast; random stuff ... not a lot of use.
So far the two round propane tanks have provided for me for a week and a day...

Curious as to what suggestions/thoughts you all out there may have for me!

RoverGirl

DougJ

  • ---
  • Posts: 549
Re: Propane! ... new full-timer ;)
« Reply #1 on: March 24, 2005, 01:04:41 PM »
We've only had a motorhome for two years, and during that time we always travel with the propane fridge / freezer running.  I've read several opinions in support of doing this.  In our case, the fridge has an electronic ignition system so I'm thinking (but an expert may need to correct me) that we're quite safe in running with it on.

Ciao,

Doug

Steve, CDN

  • ---
  • Posts: 2389
  • VA3VH
    • The Pallys
Re: Propane! ... new full-timer ;)
« Reply #2 on: March 24, 2005, 01:43:58 PM »
Your propane question is a very good one, though there is contraversy on the answer.

According to Mac McCoy who gives the fire prevention seminars at FMCA rallies, the propane valve at the tank should be turned off while driving.  The reason is that in the event of a major accident where the pressurized propane line might get severed, it could present a fire hazard.  His recommendation is to install a small battery operated fan (available in most RV supply stores) in the fridge which causes the air to circulate.  The fan does the same thing as in a convection oven, to increase air flow and heat transfer...but for the cold air.   If you drive for 5 - 6 hours, and not open your fridge you food should remain cold.

OTOH there are a large number of RVers who travel with the fridge on without any problem.  An electronic ignition system should re ignite the pilot if it gets blown out while in motion, so the fridge will stay cold.

Another option is to turn off the propane and drive with the generator on to provide electricity to the fridge.

It will be interesting to read more opinions on this subject, which has many points of view.

Welcome to the RV Forum, and hope you will make it a regular part of your online activities.

Feel free to join in any of the ongoing discussions in the Forum to offer your comments.

After you've had an opportunity to look around, please respond to our poll
Steve, Forum Moderator
Home Page
My Polar Bear Mural

DonJordan

  • Former Staff
  • ---
  • Posts: 354
Re: Propane! ... new full-timer ;)
« Reply #3 on: March 24, 2005, 06:43:29 PM »
Hi and welcome to the RV Forum.  Glad to see that you found us.

Re your question on propane and running the refrigerator while underway, there are safety reasons for shutting off the main propane valve at the tank(s) while driving, but I am pretty certain that the majority of RVers travel with the propane on and the refrigerator running.  With the newer refrigerators propane ignition is by automatic spark start so even if the flame blows out (unlikely) it will automatically restart.

I'd be surprised if your propane tanks are low after only a week of full timing.  The only reason that they might be would be if you have a leak in the system.  Your refrigerator and range should run a lot longer than a week if you have two cylindrical tanks.  Do you have the automatic cross over valve that switches tanks when the first runs empty?
Don Jordan.

Ron

  • Former Staff
  • ---
  • Posts: 18087
Re: Propane! ... new full-timer ;)
« Reply #4 on: March 24, 2005, 09:43:37 PM »
Hi,

We are gld you found us.  Welcome to the RV Forum.  Regarding your question regarding propane usage I doubt very much your tanks are anywhere near empty.  What does the gauge show? I would suspect you haven seen it move off of full yet.

Ron & Sam-home is where we park it. Currently located   HERE

Gary RV_Wizard

  • Forum Staff
  • ---
  • *
  • Posts: 60773
  • RVer Emeritus
Re: Propane! ... new full-timer ;)
« Reply #5 on: March 25, 2005, 09:33:03 PM »
Hello Rovergirl and welcome to RV Forum Community,
If yo have only been running the refrigerator, I doubt if your propane tank(s?) are anywhere near empty. You would be amazed at how little the fridge consumes - or the stove either.  But since you are bondocking, you may be heating water and that uses a bit. Even then, you probably still have weeks yet to go.

What size tank or tanks do you have?
Gary
--------------
Gary Brinck
Summers: Black Mountain, NC
Home: Ocala National Forest, FL

Lou Schneider

  • Forum Staff
  • ---
  • *
  • Posts: 7374
Re: Propane! ... new full-timer ;)
« Reply #6 on: March 25, 2005, 11:35:14 PM »
Hi Rovergirl!

Propane is stored in liquid form inside your tank.   Above the liquid there is the propane gas.  When you use propane, you draw off some of the gas, which is then replenished from the liquid.

You're interested in the amount of liquid propane in the tank.  When it's gone the tank is empty.

An easy way to find the level of the liquid propane is to pour some hot water down the side of the tank, then feel along the side with your hand.   You'll find a distinct contrast in temperature at the level of the liquid - the gas above the liquid won't absorb much heat, so the tank wall will be warmed by the hot water.   Liquid propane is an excellent heat sink, so the tank will remain cool below the level of the liquid.

Sometimes you can see a condensation line at the level of the liquid's surface after you pour the hot water onto the tank.

If you want to estimate your gas usage, look on the nameplate of each gas appliance for it's input in BTUs.   If you know that a gallon of propane contains approximately 80,000 BTUs you can tell how much fuel the appliance uses per hour by dividing it's BTU rating into 80,000.   For example, if your water heater  has a 12,000 BTU rating, it uses (12,000 / 80,000) or about 1/6 gallon of propane each hour the flame is on.

Stove burners use about 6500 BTUs for a standard burner, 9000 BTUs for a high output burner.   These are with the flame full on - if the burner is turned lower it uses proportionately less.   An oven burner uses about 9000 BTUs.   The little flame in your refrigerator uses about 800 BTUs.

The largest user is your furnace - depending on it's size iit can use anywhere from 20,000 - 35,000 BTUs

If you have two propane tanks, the regulator will automatically draw from one tank until it is empty, then it will switch to the second tank.  There should be a little lever on the changeover valve - turning it determines which tank is the primary tank.   When the primary tank is empty, a red flag will pop up in the little window and the regulator will begin drawing from the second tank.

I usually wait until my first tank is empty before getting propane.  Many propane places have a minimum charge, and going there with an empty tank ensures you will buy more than the amount needed to reach their minimum.
« Last Edit: March 26, 2005, 12:04:18 AM by Lou »

Gary RV_Wizard

  • Forum Staff
  • ---
  • *
  • Posts: 60773
  • RVer Emeritus
Re: Propane! ... new full-timer ;)
« Reply #7 on: March 26, 2005, 09:04:52 AM »
RovrGirl,
To address your other question about traveling with the propane tanks on, I would say it is a standard practice except in areas where it is specifically forbidden. These are tunnels that dip under things (rivers, for example) and subterranean parking garages.  The  is because propane is heavier than air and any leaking gas would accumulate in the lower areas until eventually a passing vehicle ignited it. Such places will usually have warning signs but don't always have a place to stop to go close the valve.

You must also turn off all propane appliances while in a fuel station because operating propane appliances have an open flame. That's pretty obvious but easy to forget.

The federal DOT and the various state's fire marshall's regulate the carrying and use of propane in vehicles. LP gas regulations are very stringent but NONE of them have prohibited use of gas refrigerator's or other appliances while in motion and NONE of them have required the main valve be shut off (except the special cases noted above).  On the other hand, I think it is clear that shutting off the main valve provides some additional safety margin in the case of a severe accident. It's up to you to determine what you are comfortable with in terms of risk.

I'm one of those who routinely travel with the gas valve on and the fridge running on propane. However, I also use the house a/c to cool the motorhome and so run the fridge on electric rather than gas whenever the genset is running to operate the a/c.
Gary
--------------
Gary Brinck
Summers: Black Mountain, NC
Home: Ocala National Forest, FL

Karl

  • Former Staff
  • ---
  • Posts: 5154
  • No Brett; no sweat. A QB's not the whole team.
Re: Propane! ... new full-timer ;)
« Reply #8 on: March 27, 2005, 12:57:52 PM »
RoverGirl,
As was said previously, propane use by the fridge is minimal. Fuel gauges are notoriously inaccurate, but if it shows 'full', it probably is or nearly so based on what you said you used it for. Also, it would help to know what type of rig you have. If you have a propane generator or a portable one you set on the ground, then using it while travelling is not an option for obvious reasons. Besides, a fridge runs much more efficiently on propane than it does on electricity, and you'll be wasteing  a lot of gasoline. BBut, as Gary said, switching over to elec. while running the genset for other reasons makes sense - just make sure you switch back (if it doesn't automatically) to propane or you'll run your house batteries down in a hurry - and I speak from experience!!!

Welcome to the Forum and a whole new lifestyle!
Karl (Cheesehead) Kolbus   Life's journey is not to arrive at the grave safely in a well preserved body, but rather to skid in sideways, totally worn out, shouting "...holy cow ...what a ride!"

RoverGirl

  • Posts: 2
Re: Propane! ... new full-timer ;)
« Reply #9 on: March 27, 2005, 08:53:55 PM »
You all are WONDERFUL!
thank you so much for all of the great information.
i recently stopped at a U-Haul and bought two new gauges (that actually work), one each for my 2 propane tanks, and
lo and behold, they were both still reading full!  So you guys aren't kidding when you say they will last a while ;)
I still haven't done anything but dry-camp and I've been going for a week and a half.
I so enjoyed reading your replies, and I'm even going back to read them again to glean all of the info i can.
thanks for hanging out online with me while i'm out there on the road ... ;)
my best,
RoverGirl :D

DonJordan

  • Former Staff
  • ---
  • Posts: 354
Re: Propane! ... new full-timer ;)
« Reply #10 on: March 27, 2005, 09:45:37 PM »
RoverGirl,

Glad that you found our information useful.  Stick around and participate on a regular basis and I think that you will get a lot of information and enjoyment from the forum.
Don Jordan.

Ron

  • Former Staff
  • ---
  • Posts: 18087
Re: Propane! ... new full-timer ;)
« Reply #11 on: March 27, 2005, 10:42:36 PM »
RoverGirl,

Glad we could be of assistance.  Please feel free to ask more questions should they come up.  Also please provide answers to any questions that you may the answer to.

Ron & Sam-home is where we park it. Currently located   HERE

Carl L

  • Forum Staff
  • ---
  • *
  • Posts: 7303
Re: Propane! ... new full-timer ;)
« Reply #12 on: March 31, 2005, 03:00:58 PM »
hi All!
I'm new to this board ... and new to full-timing as well, but that's what i'm up to!
I've been out now for just 7 days, dry-camping the whole time so far ...
I don't think that my propane tanks have a proper working gauge on them ... so i'm getting pretty close
to thinking i'd better go get them filled again (this will be the first time).  I've been running my refrigerator full-time
with the propane tanks on while i drive.  One question -- is this a no no?  I need my fridge to run while i drive so I don't
see that turning the tanks off is an option!  Any thoughts? 

Yeah, leave them on.   I have been doing so for some 10-15 years and have no problems to report about propane tanks on while driving.      If you pull onto a ferry, US Coast Guard requirements say turn them off.   Do so and turn them on again when you drive off.   As long as you don't open the fridge you should be ok.    Some states require that when you refuel the tow vehicle at a gas station.    That said, do turn them off at the tanks went you put the trailer in dead storage.
Carl L/LA   [Forum Staff]  KI6SEZ

Prowler 23LV TT pulled by a '95 Ford Bronco

Smoky

  • ---
  • Posts: 3591
Re: Propane! ... new full-timer ;)
« Reply #13 on: March 31, 2005, 05:45:56 PM »
Rovergirl:

Count me in with the "run with propane on" gang.

We are right behind you in fulltiming, getting ready to upgrade from 30 foot trailer to Class A pusher in mid May.  We are moving to Montana as our place of residence, but in reality will be following the 70 degree line wherever it goes.

What kind of rig are you running and where are you dry camping?

Smoky S  Ham radio - W3PY

The magic of a campfire
where the fish get bigger
the mountains get higher
the hike was uphill both ways
and new friends become old friends

2005 KSDP3910 Newmar Kountry Star
Toad - Taurus wagon w/ axle lock
On our way to the Poudre River in Colorado for the summer!

Steel Rat

  • ---
  • Posts: 6
Re: Propane! ... new full-timer ;)
« Reply #14 on: March 31, 2005, 06:27:04 PM »
Funny. I haven't done a LOT of RVing yet, but when I drove from Washington State to Illinois, I had the Propane off, and the fridge in Auto mode, it ran off the electricity of my truck. I'm guessing from the conversation that this isn't always the case.

Jeff

Ron

  • Former Staff
  • ---
  • Posts: 18087
Re: Propane! ... new full-timer ;)
« Reply #15 on: March 31, 2005, 06:50:06 PM »
Funny. I haven't done a LOT of RVing yet, but when I drove from Washington State to Illinois, I had the Propane off, and the fridge in Auto mode, it ran off the electricity of my truck. I'm guessing from the conversation that this isn't always the case.

Jeff

There were some fridges that were three way 120VAC, GAs, or 12DC.  I am not sure if they are even available anymore most of the ones I see now are 120VAC or Gas.  Maybe you had one that could use 12DC.
Ron & Sam-home is where we park it. Currently located   HERE

Steel Rat

  • ---
  • Posts: 6
Re: Propane! ... new full-timer ;)
« Reply #16 on: March 31, 2005, 07:50:49 PM »
Quote

There were some fridges that were three way 120VAC, GAs, or 12DC.  I am not sure if they are even available anymore most of the ones I see now are 120VAC or Gas.  Maybe you had one that could use 12DC.

Quote

I thought the inverter changed everything to 120. My Fifth wheel is a 2002 model, Dometic fridge (Is there any other kind?). It has two buttons, On/Off and Auto/Gas.

Ron

  • Former Staff
  • ---
  • Posts: 18087
Re: Propane! ... new full-timer ;)
« Reply #17 on: March 31, 2005, 08:14:42 PM »
Usually the fridge AC is not included in the inverter feed outlets.  Would take a pretty good bank of batteries to operate the fridge from the inverter output.
Ron & Sam-home is where we park it. Currently located   HERE

Phil

  • ---
  • Posts: 982
Re: Propane! ... new full-timer ;)
« Reply #18 on: March 31, 2005, 11:16:40 PM »
Usually the fridge AC is not included in the inverter feed outlets.

Ron,

My fridge is on the inverter and, most of the time I wish it wasn't.  I just manually switch to gas when I dry camp with the inverter on.  One of Monaco's (not) better ideas.  :)

Phil

Ron

  • Former Staff
  • ---
  • Posts: 18087
Re: Propane! ... new full-timer ;)
« Reply #19 on: March 31, 2005, 11:22:00 PM »
Phil,

Our fridge is not on the inverter and I like it that way.  I have met a couple RVers that have installed a inverter just for the fridge.  Guess that is ok while your running but sure would run the batteries down when boondocking.
Ron & Sam-home is where we park it. Currently located   HERE

BernieD

  • ---
  • Posts: 5815
    • PressurePro
Re: Propane! ... new full-timer ;)
« Reply #20 on: April 01, 2005, 08:38:17 AM »
I'm really not so sure why all the refer inverter bashing ??? I had our refer put on our inverter circuit when we bought the coach. I prefer having the refer run on electricity when traveling on the highway, the alternator keeps the battery bank full, so there is no drain. When we drycamp it is very easy to push the button to switch to LP only to avoid the battery drain. Not such a big deal.
Bernie & Marlene Dobrin
Home is Goodyear, AZ
Missing our Travel Supreme

Ron

  • Former Staff
  • ---
  • Posts: 18087
Re: Propane! ... new full-timer ;)
« Reply #21 on: April 01, 2005, 10:04:25 AM »
No one is bashing refer inverters hookups Bernie.  Just normally the refer is not connected to the inverter unless requested.  Its one of those things some do and some don't.  When boondocking if one forgets to switch over to gas running the refer on battery will shorten the time between regharging batteries. ;D
Ron & Sam-home is where we park it. Currently located   HERE

Tom

  • Administrator
  • ---
  • *
  • Posts: 44570
    • RV Forum web site
Re: Propane! ... new full-timer ;)
« Reply #22 on: April 01, 2005, 10:45:09 AM »
Interesting Ron. Our refr on the Monaco came wired to the inverter. When we first had the coach, the alternator wasn't charging the house batteries, so they'd die in short order if I switched the refr to AC while going down the highway. When I posed the question here, I received mixed responses, similar to the ones in this topic. When I checked the schematics for the coach, they confirmed that the refr is supposed to be plugged into a duplex running off the inverter, and the house batteries are supposed to be charged from the alternator. It took the factory tech a few minutes to find that a wire had been placed on the wrong terminal of a relay. All now works as intended, although I must admit we often run on propane.
Tom.  Need help? Click the Help button in the toolbar above.

Ron

  • Former Staff
  • ---
  • Posts: 18087
Re: Propane! ... new full-timer ;)
« Reply #23 on: April 01, 2005, 11:47:11 AM »
Tom,

I have seen coaches wired both ways but most that I have come in contact with close enough to see how they are wired do not have the refer wired to the inverter.  There are some benefits of the refer running off the inverter for sure.  The only down side I can think of is if one didn't know this or just forgot to manually switch over to gas while boondocking.  I have considered placing another outlet in the refer compartment that will have inverter power so I can plug in while traveling.  Just hasn't been very high on the piority list.
Ron & Sam-home is where we park it. Currently located   HERE

Tom

  • Administrator
  • ---
  • *
  • Posts: 44570
    • RV Forum web site
Re: Propane! ... new full-timer ;)
« Reply #24 on: April 01, 2005, 11:50:25 AM »
That's certainly a good reason not to have it wired to the inverter Ron, and maybe that's the subconscious reason I normally run on propane. But, every now and then I think of the potential fire hazard, and switch to AC.
Tom.  Need help? Click the Help button in the toolbar above.

Ron

  • Former Staff
  • ---
  • Posts: 18087
Re: Propane! ... new full-timer ;)
« Reply #25 on: April 01, 2005, 12:08:28 PM »
The biggest reason I even consider putting a inverter feed outlet in the refer compartment is to keep the ice maker working while on the road. Like I said not a real high priority.
Ron & Sam-home is where we park it. Currently located   HERE

Gary RV_Wizard

  • Forum Staff
  • ---
  • *
  • Posts: 60773
  • RVer Emeritus
Re: Propane! ... new full-timer ;)
« Reply #26 on: April 01, 2005, 02:26:38 PM »
I have my ice maker on an inverter circuit  but not the fridge (the fridge ice maker has its own power plug).  My choice, since I added the inverter myself. That way the ice maker still works when we are boondocking but the automatic ac/gas switch on the fridge handles everything else nicely.  Since I have both types of outlet in the fridge compartment I could easily change the fridge over to an inverter-powered circuit either permanently or when circumstances made it practical, but I have never seen a reason  to do so.    Just my way of doing things and certainly not the only way.

I can see an advantage in the inverter-only approach because you never have to remember to switch the fridge off and then back on when fueling. That trades off against stops that are lengthy enough to make continued cooling powerdesirable, where you have to remeber to switch manually to gas. Perhaps six of one and a half dozen of the other?
Gary
--------------
Gary Brinck
Summers: Black Mountain, NC
Home: Ocala National Forest, FL

Lou Schneider

  • Forum Staff
  • ---
  • *
  • Posts: 7374
Re: Propane! ... new full-timer ;)
« Reply #27 on: April 01, 2005, 07:20:31 PM »
Quote
recently stopped at a U-Haul and bought two new gauges (that actually work), one each for my 2 propane tanks, and
lo and behold, they were both still reading full!  So you guys aren't kidding when you say they will last a while
What kind of gauge did you get?   If it's a pressure gauge, it won't work the way you want.

Propane isn't compressed gas - it's gas that boils off from liquid.  The pressure in a tank of propane will remain constant until all of the liquid propane is gone.  A meter that reads the gas pressure at the tank outlet won't show you how much propane is left in your tank.   Liquid propane is something like 200 times more concentrated than the gas, so when the liquid is gone the tank is essentially empty.   Since the pressure remains constant until all of the liquid is gone, a pressure gauge can't tell you how much propane is in the tank.

In order to get a real level, you have to replace the whole outlet assembly with one that has a gauge driven by a float extending into the tank.  Is this what you got?

The other type of gauge that is truely accurate is a strip that goes on the outside of the tank.   It's made from liquid crystals that change color when you pour hot water over it.   Like running your hand along the outside of the tank, the tank (and the strip) will get warmer and change color where there's gas and stay the same color where there's liquid.
« Last Edit: April 01, 2005, 07:26:21 PM by Lou »

Gary RV_Wizard

  • Forum Staff
  • ---
  • *
  • Posts: 60773
  • RVer Emeritus
Re: Propane! ... new full-timer ;)
« Reply #28 on: April 02, 2005, 08:01:26 AM »
Quote
The pressure in a tank of propane will remain constant until all of the liquid propane is gone.

Isn't that a little bit overstated, Lou?  The tank pressure will vary some as the liquid propane level goes down, though nowhere near in proportion to the level of the liquid.   And the pressure also varies with ambient temperature (either up or down) or the sun shining on the tank, further complicating things.

I readily agree, though, that pressure-type gauges aren't very reliable propane level  indicators.  Generally they will show FULL until nearly empty and then drop very quickly, giving you little if any warning.
Gary
--------------
Gary Brinck
Summers: Black Mountain, NC
Home: Ocala National Forest, FL

Karl

  • Former Staff
  • ---
  • Posts: 5154
  • No Brett; no sweat. A QB's not the whole team.
Re: Propane! ... new full-timer ;)
« Reply #29 on: April 02, 2005, 02:19:49 PM »
Gary and Lou,
You're both right - to a degree. Almost all matter can exist in one of three 'phases' - solid, liquid, and gaseous(vapor). The point at which a solid becomes a liquid is the melting point; the point where a liquid becomes a gas is called the boiling point. It all depends on a combination of temperature and pressure. Interestingly, some substances can exist as a solid, liquid, and vapor all at the same temperature/pressure. This is called the triple point, but is not pertinent to our discussion of propane. If you evacuate a container and then pour in some propane (C3H8), some of the liquid propane will change phases and go from liquid to vapor until equilibrium is reached and it is at this temperature/pressure combination that the process stops. In truth it still continues, but an equal amount of gas returns to the liquid phase, so the net change is zero. At equilibrium you can measure the pressure of the gas in the cylinder, and that is what's called the vapor pressure. At equilibrium, if no additional heat is added or lost and the pressure remains constant (as it would in a closed container like a propane tank) the respective volumes of liquid and gas will remain constant. As you draw the gas off (like turning on a stove burner), the pressure inside the container will drop and more of the liquid will change into the gas phase and the vapor pressure will remain constant.  This is true until there is no more liquid in the tank to change into vapor. At that point, the pressure of the gas being drawn off will continue to drop until it finally equals atmospheric pressure; then flow will stop. It is for these reasons that a pressure gauge is useless for determining the amount of liquid propane remaining in a tank. As Gary mentioned, temperature is one of the variables in determining vapor pressure. If your tank becomes hot, the pressure will increase and force some of the vapor back into the liquid phase. Too much heat, and there won't be much vapor left to convert back to liquid, and the pressure could reach dangerous levels.   Conversly, if you were to travel to a place where the temperature is -108F and had a normal atmospheric pressure, no gas would flow at all because you would be below the boiling point of the propane (-107.1F). I don't think many of us have to worry about that! ;D  There is another temperature/pressure combination referred to as the Critical Point. For propane it is 204F at 609lbs/sq. inch. It is at the critical point where no amount of additional heat or pressure will change the gas back into a liquid. Obviously, the safety pressure relief valves on our tanks are set well below that point.
Karl (Cheesehead) Kolbus   Life's journey is not to arrive at the grave safely in a well preserved body, but rather to skid in sideways, totally worn out, shouting "...holy cow ...what a ride!"

 

Hosted by Over The Network