I've got a Hipólito 250 CP produced in 1994 that I just fired up for the first time very recently and have used only a few times since then. Besides finding out that the needle height was set WAY too high during factory assembly and resolving that problem, everything has seemed basically OK--if you don't count the fact that every time I've used it it's suddenly flickered and burst into flames in a split second after burning trouble free for around 1-2 hours . I have wondered if the problem might be a drop in pressure, so I began to investigate. I had taken due care to read the lantern's included user manual, which is written in Finnish, prior to doing anything with the lantern. It mentions that the lantern should be pressurized to just below the red line prior to lighting, and that while the rapid starter is running for 40-60 seconds the pressure should not be allowed to drop below the red line . This obviously doesn't make sense, as it never mentions at what point the pressure should reach or surpass the red line. But what's really scandalous is that nowhere in the entire manual does it say that the operating pressure should be increased following ignition. Owning and using other lanterns I'm of course aware of the fact that more pressure is added following ignition, but I've been operating this lantern according to the manufacturer's instructions and running into this extremely dangerous situation every time. I've quickly learned that pressure lanterns should never be used without a fire extinguisher within arms' reach. After DuckDuckGoing (that's an action verb nowadays ) the Petromax user manual for the comparable lantern, I learned that the pre-ignition pressure is 1.5 bar and the normal operating pressure is 2.5 bar. Why on Earth did the engineers at Petromax not hand this information over to the ladies at Hipólito for inclusion in their manuals?! Every time I've experienced the problem described above, I would say that the pressure has been at around 1.25 bar. The Petromax manual states that when the pressure falls below 1 bar more pressure should be added to bring it back up to 2.5 bar. For a certainty I've never let my pressure dip below 1 bar and I've still had this issue. Both the Hipólito and Petromax manuals state that if the light grows dim or flickers, the handwheel should be quickly operated to lower and raise the needle, but I can say for sure that the problem comes so suddenly and so severely that there is no possibility of this working. The only thing to do is extinguish the lantern by opening the screw on the manometer and turning the handwheel to raise the needle. The lantern then needs to be cooled and time must be taken to disassemble and clean the whole upper portion to remove all the soot. I've taken the time to scan the whole Finnish user manual for the lantern, which is actually the H 502 manual with the actual lantern model (H 202) stamped on the front cover.
Hi Jaska, I do not know but I can throw in some suggestions. - Got lost during translation. What is your overall impression on the text? Did a native speaker with some knowledge on lanterns write it or was it translated from German using a wordbook? - As the Manometer (pressure gauge) does not indicate an exact amount of pressure (although there are some numbers printed on the dial) it only tells you: "The pressure will most likely be higher when the indicator moves to the right". We call these items "Schätz-Eisen" (Iron lump which only gives a wild guess on the pressure inside not necessarily connected to reality) So they left it out on purpose? Erik
I cannot add to what Erik says above, but no lantern should do what you say is happening. When the pressure drops in my hipolito/petromax/anchor it just goes dim then goes out. No massive drama.
Erik, I think the Finnish language in the instructions is just fine. Non-native speakers of Finnish would probably never have attempted to translate into Finnish back in 1994. It seems like a case of Hipólito just writing and translating oversimplified instructions that lack critical details. For example, it isn’t even mentioned that the lantern can be preheated with spirits. There are some curious technical mistakes which probably amount to carelessness on the part of the translator, such as advice to raise and lower the needle once or twice with the handwheel when the light dims and flickers and the lantern makes a sputtering sound. Wouldn’t one lower and raise the needle rather than raise and lower it in that case? Fireexit1, that’s been my experience (similar to yours) with most other lanterns as well. I have taken care to check and reset, as necessary, the gap between the Jtube and jet, as well as check the mixing chamber and ceramic burner for tightness. They seem to come a bit loose after every usage, even after using a bit of mantle tie in the threads. This lantern runs just perfectly until suddenly it goes POOF. It comes with no forewarning at all. Whether it has to do with a drop in pressure I don’t know, but it’s always happened when the pressure is just a bit below the red line and around 1–2 hours into the burn.
Hmm, that’s my own mind playing tricks on me when I’m writing and thinking in two languages. That part of the instructions is OK.
Jaska, to me it sounds like the lower pressure reduces the heat output from the mantle, reduced heat is allowing the vapouriser to cool down and then liquid fuel is passing through the jet. The liquid fuel then bursts into flames. The mantle could also be too far from the vapouriser. Are you using a bulbous (ball like) mantle or a Coleman style (straight sides) mantle. Bulbous mantles usually work better at keeping the vapouriser hot.
Martin, that sound very well informed. The mantle is the original Luxor that came with the lantern. I re-lit the lantern last night after experiencing the problem and pressurized the fount to 2.5 bar to see if it made a difference. It burned wonderfully for around an hour before I had to extinguish it and go to bed. I’ll try it again tonight and see what happens.
We'll probably not know for certain, whether that was really due to oversimplified, missing contents or deliberate omission in the translation. Anyway, the basic or earlier original design of such lanterns do not incorporate pressure gauges. The knowledge of the actual pressures inside the fount were really never viewed-upon as an essential pre-requisite for operations. The original design relies on a somewhat 'rough' estimate by the operator, as to how much pressure is required, both during startups and operations. The startup would be by means of the soft, preheating by spirit flame. The lanterns were not pressurized prior to adequate preheat. Once the preheat is done(just before the spirit burns out), the operator is only required to pump up the lantern until he/she 'feels' that the light output is adequate or bright enough. Therefore, we can't rule out the possibility that it might also be due to this particular 'common understanding', that, certain less essential details had been omitted in the Hipolito's instructions.
@Jaska As for the explanation of the occurence of the trouble you had been going through, Martin ( @ROBBO55 ) had given a couple of possible reasons. Yes, I've experienced such troubles before. The event can be quite sudden, especially if the pressure is a little too low. It does not necessarily happen to all lanterns though.
In case it’s of use, here’s a look at the mantle and its situation relative to the vapouriser. Once this mantle dies the next 10 will be old Optimus No. 4 250 CP’s that I recently picked up from an army surplus store. Highly radioactive from what I’ve heard .
I have found that it's better to use a more bulbous mantle as when it burns off it forms closer to the vapouriser and keeps it hotter and therefor the fuel vapourises properly and the light is bright.
That reminds me of the HK 150. The mantle is so close to the vapouriser you can’t keep it off of it. What would you recommend for a bulbous mantle for the 250 CP? Will the Optimus No. 4 do? I haven’t seen them in action yet so don’t know whether they fit that description or not.
It still depends on what is happening. Dirt can play tricks at any pressure or fuel level. The needle is only there for cleaning purposes. Pressure INDICATORS can be checked with a gas canister as I described more then once on this forum.
Update: The lantern has been running for 2+ hours right beside me here with zero issues with pressure at 2.5 bar. At the 1 hour mark the pressure had dipped to 2 bar so I repressurized the fount and spun the handwheel 720 degrees just for the pure excitement of it. I used it last night for a shorter period and it worked equally well. I hope it will continue on like this for the long term. It really is a nice lantern.
