Propane light says full but is empty

[Flame]

Just a quick question before we head to Tennessee in the morning. The "test button" for checking holding tank levels,battery charge, and propane level has always read empty for the propane. That is good because we don't use it but for some reason it now reads full and I don't have any in it. Can anyone explain what is going on? Anything dangerous happening here I should be aware of? Probably just a sensor gone bad but would like to know.

[Blue~Go]

My first question would be what does the manual gauge say? By that I mean the dial gauge that is right on the side of the tank by the knob you use to turn it on and off. Note that the scale on the dial gauge is not linear in terms of full/empty so you need to look at it carefully. Sometimes I'm lazy and use my phone to take a photo of it and look at that.

Also, do you have the tank turned on or shut off at the hand wheel?

There are other possibilities, and the dial gauge is not infallible, but I'd start with finding out the two things listed above and then go further from there.

BG

PS: How do you "know" that the tank is empty? Just asking so we can use it as another clue.

[Flame]

Ok Blue, I originally assumed it was empty because the inside panel light said it was empty. I believe my friend did the test by removing the fill cap and poking something in there to see if it had any pressure on it. Also you asked if the valve knob is turned on or off. It is wide open right now. The underneath gauge you spoke of I do not see. There is a black plastic original type cover just to the right of the on/off/knob but it is held in place by 2- 1/4 inch bolts and nuts. Is a gauge behind that cover??

[Flame]

I removed the black plastic cover and all that it is protecting is the regulator. I turned my furnace on at the inside control and after a few moments it did come on and blows real strong and pretty darn quiet too. I let in run approx. 20 minutes and nothing but cool air blowing out. I had the outside knob turned wide open. I saw no gauge of any kind under the rv and the one inside still reads full. Maybe it is just full of air? I was running around with the valve open. I don't have the book to the furnace heat so bear with me. I assume you have to run the generator when running the furnace but maybe a electric space heater would do just as good. Then at least you are not burning gasoline and propane both to stay warm. What am I missing??

[caconcourse]

Hi Flame,

The easiest way to check for the presence of propane in the tank is to try to light the stove. The furnace does not require the generator or electrical hookup. The furnace fan and controller run off 12V, and the heat of course uses propane. The thermostat control for the air conditioner also controls the furnace, but only uses 12V when operating the furnace.

[Flame]

Thank you CalCon, How bad is the furnace and fan motor on the carriage batteries? How long do you think it could run on a set of fully charged batteries if the batteries are in newlike condition?

[chin_k]

I would trust the gauge on the tank more than the panel. The gauge tells you how much liquid propane is in the tank. The "empty" portion should be full of propane vapor, even when it is completely empty. If not, I think you may need to vacuum/purge the tank, but I can be wrong.

As for the electrical load of the furnace, I think it is not trivial. I think you should be able to run it for one whole night with a full battery, but I don't think I used it that much since we never got anywhere really cold. You can crank up the generator for a few hours and recharge the battery if it low. It sure beat using the heat pump or heating coil to heat if you still have propane available.

[caconcourse]

Thank you CalCon, How bad is the furnace and fan motor on the carriage batteries? How long do you think it could run on a set of fully charged batteries if the batteries are in newlike condition?

The furnace fan is probably similar in power draw to the fantastic fan, which is not a huge load, but not insignificant. Solar could probably recharge to allow almost continuous use, but it could certainly run overnight and then some. It doesn't have to run continuously either, as the thermostat will allow it to cycle on and off as needed for a set temperature, which could be set quite low, just to avoid being super-cold.


I have run the fantastic fan for days in the driveway, using solar to recharge in the day, but I have 150W of solar (3 50 watt panels) and it is in sunny Southern California. In fact, I leave the 12V system on all the time, and have not tripped the LVD in over a year of continuous operation. The only thing that drained the batteries and triggered the LVD was the refrigerator running on DC, and I have stopped doing that. (I leave the fridge off while driving and switch to propane when being used while parked or camping if no shore power is available). We usually need propane about once a year. Running the refrigerator on DC not only consumed the batteries within an hour or so, but also did not do a good job keeping the refrigerator cold.

[Blue~Go]

This is what the gauge looks like on my stock Chinook propane tank. Because of the angle it's slightly hidden behind the metal guard; but in real life it's fully visible.

As mentioned above, I'd test with a stove burner. The furnace is much more likely to have some other problem that causes it to run but not heat. Not saying it does have a problem, but the stove burners are much simpler in terms of parts and pieces.

If it is empty, then of course you can have it filled. I like to go to a real propane place, because having a high school kid at a convenience store fill my tank just doesn't give me the happies (even though they might be just great). Also, our valve points downward a bit. So the usual rigid fill nozzles can be a slight issue (which you can get around by putting one layer of Lynx blocks under the passenger side wheels). But a real propane place will usually have a "soft" hose of a few feet long that they can attach to the big nozzle, thus making it easy.

PS: If the gauge on your stove hood is giving you trouble, it might just be the wire or the connection. IIRC it's a yellow wire that goes from the gauge, behind the dining wall, then into the furnace area (rear side by wall) and then through the floor to the propane tank. I could easily imagine a flaky connection down there.

[Flame]

Well Blue, I saw the item you arrowed to but did not realize that was a gauge. Now I know and I will look again later. I did go ahead a store a nice electric heater in the rv for insurance. Fixin to hit the sack. Leaving out at 6am tomorrow. Thanks for all the advise from everyone. Off to Smokey mountain Christmas!!!!