A Caution on Lanterns Indoors

[AL_as_needed]

Figured I'd pass my little adventure on to those of you whom also have little lanterns aglow indoors.

Now not going to lecture about having proper ventilation, nothing flammable around the lamp/lantern etc....  However what also needs to be considered (and easily overlooked) is the fuel level.

Eagerly awaiting my No2 Blizzard to be completed, I decided to light my Dietz Comet and give it a nice run this evening.  All well and good, i check the fuel level and figured I'd add some (was about 1/2 a tank). Normally I aim for 3/4 full, but given the small size of the comet, it filled it to just a hair above the bottom of the fuel font threads. This was a big mistake.

As the lantern was lit and ran for maybe 20 min, all was good, or so I thought. I became distracted as always and the lantern was left to its devices for some time. In that time the lantern fully warmed through, air tubes were well heated especially given the small size of the Comet.

As the temp rose, the fuel warmed and expanded, pushing up into the very bottom of the burner.  Once there, warming even further, gassing off, and mixing with the lanterns natural draft via the air tubes.....The flame was free to grow as far as it desired. This is what is known as a run away lantern. The symptoms compound and next thing you know, the flame is up and out the chimney cap. 

Not sure how long it was running in that state before I dropped the wick and blew it out,  but the room was well filled with the haze of smoke. My saving grace was the chain I use to hang my lanterns from. That extra few feet away from the walls/ceiling prevented them from getting too hot. Also, kudos to the Comet for taking the heat and keeping the fireball inside itself as much as it could. The little guy was very very hot, to the point where the paint on the chimney cap seems to have begun to burn off/darken by the heat. 

So the lesson here is twofold:

1)  3/4 full is the safe maximum fuel level for a working lantern to provide expansion.

2) Dietz Lanterns are fairly safe, but to not rely on prior experiences to foresee future outcomes. Safety is a full time job. Yes it's a hobby collecting these little gems, but fire is fire, and the risks are still the same now as when these were the main sources of lighting decades ago.

[twocvbloke]

One of my chinese lanterns that I keep out in the shed has a unique anti-overfilling feature, as soon as it gets near to the level of the air tubes, it starts dripping due to being poorly made and only pressed together rather than soldered or welded, so it never gets more than 3/4 filled, barely makes it past 1/2 to be honest, so thankfully shouldn't suffer a runaway...

And it's why I keep it in the shed, better that burned down than the house!! 

[TelePlay]

Interesting, #8 in their FAQ deals with over filling but they only say it causes fuel to leak out, not catch fire. Leaks like twocv mentioned. You must have a very well put together lantern there.

I think my filling practice is a half tank or so. I have had a few run completely out of fuel (requires a wick trim after that) so have learned to check the fuel level each time I light one up. Just shaking isn't enough to it's a visual inspection.

[AL_as_needed]

Interesting, #8 in their FAQ deals with over filling but they only say it causes fuel to leak out, not catch fire. Leaks like twocv mentioned. You must have a very well put together lantern there.

I think my filling practice is a half tank or so. I have had a few run completely out of fuel (requires a wick trim after that) so have learned to check the fuel level each time I light one up. Just shaking isn't enough to it's a visual inspection.

I noticed on my comet, and I'm not sure if this is due to its small size, but the base of the burner is a very very snug fit into the top of the tank. My theory is that it was leaking into that air chamber at just the right rate (rather slowly) to gas off before really making it out of the lantern elsewhere.

Could also be the simple fact it was made in the US with good metal and tooling, and checked against a level of quality control that conveyed the pride of the men and women who made them. Darn american made stuff  actually being quality that lasts 50+ years.....

[andy1702]

I've never had a runaway wick lamp, but a 'Tilley' lamp is another story. If you don't warm the mantle enough before attempting to light, it's possible to get flames leaping out of the top. I'm not sure exactly how I did it and have never been able to repeat it. But the day it happened I got quite a surprise!

[19and41]

I always give my lamps and lanterns their first test outdoors.  When I test them I always think of those old westerns in which a conflagration was set with one in a house, shack or barn.  If they give a good acquittal of themselves then I may bring them in, under close supervision.

[twocvbloke]

One useful thing about using them outdoors, put some citronella oil in the tank and it keeps the bugs away, did that today (nice sunny hot day, flies were annoying the youknowhat out of me) after I'd mowed & was a bit sweaty, and the bugs stopped bugging me, especially useful cos I fired up the BBQ too...

[19and41]

It's nice when a collectible can multi task like that.

[twocvbloke]

Well, my lanterns aren't collectables, just cheap chinese things that I couldn't resist buying because of the low price...

Maybe someday I'll buy a vintage brand lantern, once the chinese ones have fallen to bits... 

[TelePlay]

One useful thing about using them outdoors, put some citronella oil in the tank and it keeps the bugs away, did that today (nice sunny hot day, flies were annoying the youknowhat out of me) after I'd mowed & was a bit sweaty, and the bugs stopped bugging me, especially useful cos I fired up the BBQ too...

Never use mine outdoors so never considered that. But, yes, for outdoor use a bit of citronella in the kerosene will do that. I re-read the fuel section at lanternnet and they approve of using quite a heavy mixture (50/50) in lanterns: Don't know what the final percentage of citronella would be in a 50/50 mix so have no idea of how much pure citronella would go into a quart of fuel.

5.  Crown® Citronella Torch and Lamp Fuel (#CTLP01, #CTLP02, #CTLP48) (OUTDOOR USE ONLY, cut 50:50 with kerosene to extend wick life.) Flash Point: 141 Degrees Fahrenheit 

6.  Tiki® Brand Citronella Torch Fuel (OUTDOOR USE ONLY, cut 50:50 with kerosene to extend wick life.) Flash Point: 145 Degrees Fahrenheit 

They also said not to use colored or dyed kerosene or lamp oil because it will eventually clog the wick and inhibit proper operation and it can also permanently stain the lamp or lantern.

[twocvbloke]

The citronella I used was some essential oil stuff in a little bottle, don't know the strength of it, but a few generous drops mixed into the fuel seemed to have the desired effect, couldn't really smell it much, but I guess the insects could...

[AL_as_needed]

The citronella I used was some essential oil stuff in a little bottle, don't know the strength of it, but a few generous drops mixed into the fuel seemed to have the desired effect, couldn't really smell it much, but I guess the insects could...

Or maybe the bugs were able to sense the combination of phoneitis and lanteritis once the lantern was lit. Seeking a healthy host, they moved on to your neighbors. 

[TelePlay]

The citronella I used was some essential oil stuff in a little bottle, don't know the strength of it, but a few generous drops mixed into the fuel seemed to have the desired effect, couldn't really smell it much, but I guess the insects could...

I ran the numbers on a citronella/fuel mix. Tiki brand torch oil according to the msds is 0.2% citronella and lanternnet recommend mixing it 50/50 with lantern fuel which would make it a 0.1% concentration of citronella.

So, a 64 ounce bottle (1.89 Liter) bottle of fuel could have up to 1.9 ml or about 35 drops of pure citronella oil added to it to get a 0.1% mixture. I don't know how much fuel you had in your tank but if it was about 500 ml of fuel, 8 drops would make it about 0.1%.

Of course, for outdoor use only.

Seems pure citronella in the US is just under a $1 per ml and about half that from China/India.

[AL_as_needed]

Just a follow up.

Now I use klean heat 1-k substitute (by klean strip) in all my lanterns once they are finished and tested to not leak/ function correctly. For testing however I use plain jane 1-k kerosene as I have a lot of it on hand and its a  bit cheaper here.  The comet had its little "incident" while testing on 1-k, and as john pointed out that 1-k has a much lower flash point than klean heat.

Well the comet has finally been put back into service, this time with klean heat, and its a world of difference. In the comet (haven't noticed this in the others so much) it burns brighter on klean heat and with a whiter light. Seems the size and sensitivity of the comet prefers higher temp fuel. Not to mention the reduced chance of flame outside the chimney....

[twocvbloke]

I had some Caldo Paraffin Extra, which also had a higher flashpoint according to the specs, but I never seemed to notice any difference, all I did notice was that the stuff was greenish coloured, presumably from a blue dye being added to the already yellow-dyed stuff... 

Also smelled like an eggy fart, which wasn't nice...