Hi all, now three weeks into unemployment I’ve decided to undertake some fettling to both pass the time and keep me sane… but have a minor quibble. This is a SH & S stove I got a few weeks ago. I think it’s either been an ornament or a display item as the trivet and a few other bits were painted in non heatproof paint and it’s mighty shiny… anyway… it’s ok generally good nick but I think it’s under burning. The original outer cap seems heat damaged so I’ve replaced both inner and outer with a matched Burmos pair. But having used both the original cap and the replacement there seems to be a lot of orange in the blue flames and also projecting downwards. Is this a burner issue or something else? All seals etc are replaced and tight. Anyway… pics provided so you can see for yourself plus a couple of the original inner etc. best, Chris
This pic suggests it was at that point The sound’s a sure indication though, not the usual hiss but a muffled growling sound.
The sound is actually just the normal gentle hiss - no growl. Those underneath flames are only on one side of the burner as well - apologies I should have mentioned that. Given that everything seems tight and the caps seem to be ok what would cause that? Is the burner faulty?
@presscall I might not be the best informed, but dont steel caps burn orange anyway? I am asking this too since I have a optimus 111c with steel caps that runs blue flame and orange...no soot and quiet normal hiss (compared to a phoebus 625). I thought to ask on it before I change mine out to brass
I've noticed a few times or more that even new stoves may start out blue, but when warmed up, the flame develops some orange or yellow. Duane
Id have to look at my 199, Ive used kero in it, it may have come with a m jet, might run better on Coleman Fuel. I've only fired it up a few times, never a tea test. I should have a kero jet. Duane
I should mention that the Burmos innner and outer caps I’m using I’ve used before and there’s been no sign of orange flames previously. It does just seem to be this stove. The fount also gets very hot with it too… it’s a pity because it’s actually a very attractive stove, although the trivet feels flimsy
Modern repro ones tend to, but original ones from the stove makers don’t, such as those from Primus marked as made of ‘Primus metal’. Other makers made equivalents. To test a repro example, I bought a steel cap from an online auction seller who said in his listing ‘250 sold’, or some such number. To look at it seemed ok, but in use on several stoves and with a variety of inner caps it performed very badly, glowing bright red from the off. The metallurgy of the ‘steel’ must matter. The classic manufacturers knew what they were doing.
You can see this "orange" effect with a propane torch and some scrap metal. The torch will be burning nice and blue and when you hit some metal with it you will get orange flames. Corroded metal does this the worse, and it doesn't take much. Like the infamous green flame, the orange often cleans up with use. Orange tends to be this metal/corrosion burning off, rich produces a more yellow, lazy flame IMHO.
It was more about the blue flames at the bottom really - the orange actually seems to vanish temporarily if you increase the pressure but then creep in - the ones underneath seem to be omnipresent. Is the inner cap too loose? All the inner caps I’ve tried on this burner do have a lot of play - maybe a slightly smaller spigot then unusual? No markings on the burner btw so I don’t know if original or not but guessing so
Could the downward flames be issuing not from the caps, but from cracks in the gallery, perhaps damage from past meltdown conditions while in underburn?
Downward pointing blue flames emerge through the holes in the burner skirt sometimes when the pressure is high, or if the burner caps are not quite sitting squarely on the burner. Check to see if there is any soot left on the burner after you’ve used the stove and turned it off. Tony
I find this tends to happen when the internal diameter of the outer cap isn't a snug fit and extends over the holes. This allowes the gasses to escape down the holes and ignite. Edit, I agree with what Tony posted as another possible cause.
BD also said it was sometimes the way the stove was lit. I will bow out due to limited knowledge here.
In the second photo of the stove in action, it looks like the burner head is distorted slightly- it would take a big old knock to deform a burner to the point where the outer cap won't sit straight, but it's worth carefully checking it is seating well all around its circumference. The loose fit of the inner cap is odd though- perhaps measure the spigot diameter and compare to other stoves? Silent burners often seem as much luck as science, finding the right combination of caps which work with each other AND the burner can require patience and a collection of spare caps to rummage through. On the subject of 'steel' caps- as mentioned earlier in the thread the 'Primus metal' caps were a stainless blend with a higher melting temperature- and therefore resistance to melting during underburn- than brass. Cheaper ferrous caps, from back in the day and in the case of most modern parts, are mild steel with a plating which soon burns off to be replaced by rust. Heavy corrosion creates high points which incandesce and can ignite the air/fuel mixture too early causing underburn.
@Blackdog the burner is seated ok I think it’s just the picture and my bad imaging! I’ll measure up the spigot shortly … As for the silent burner combinations … don’t even get me started Best, Chris
Hi all, apologies for resurrecting this one but I'm still trying to troubleshoot this SH & S stove. The sooting is getting worse, and it's noticeably prevalent on the outer cap now. It's also quite ingrained and hard to remove... So, to recall... Continuous tongue of orange flame emerging from the burner caps Downward blue flames through the skirt No roar of underburn - just a hiss, and the blue flame pattern seems strong All gaskets etc tight, and burner is tight Help! It's a really nice stove and I just want to get it tweaked. It performed really well on the weekend's camping trip, and it want it in regular use if possible... Best as ever, Chris
