Hello All, I am going to Yosemite in a few weeks and planning my stoves. Taking a bunch of stuff, but a new one for me is a Svea 123R. I like to test things and on a full tank I can get 4-5 GSI Ketalist water kettles to a boil with the valve about half open. The burner gets pretty hot (normal hot) and with a laser thermometer I get about 34c-35c on the side of the fuel tank. This does not change when taking a hot kettle off or putting a cold one on. My question...does anyone know the temperature that these "Chernobyl" and engage the NRV? I dont want that to happen, its why I am monitoring the temperature and also why I dont run it full blast. I run it just as I hear the chattering of the burner...as the stove runs this goes from about halfway open to about 1 quarter open. The stove. 123r with cleaning needle unknown date of manufacture Don't mind the carbon felt....
We’ve run full blast with big Sigg pots with nary a care countless times. If I ever blow a srv I’ll eat my hat, then donate five bucks to charity.
@Ed Winskill haha...ok! Yeah I just can't find a temperature to watch out for, I run it halfway open with ventilation...just like to know numbers. I have never seen a SRV fail either
Run it! If worried, keep a pot of cold water nearby to douse the hot fount. The SRV would just be doing its job, that’s what it was designed to do. So many worry about it opening. I had a Optimus 8 vent, only had a short flame of around an inch or so, but by then the fount was too hot to touch. You do get concerned. Duane
I've run my 123 full blast countless times without issue. Personally, I wouldn't worry about it. Just don't fill it all the way to the top. I also like to keep the key attached to the valve stem so I can quickly turn the stove off if something happens. This means you need to insulate the key so it doesn't get too hot to touch. I use a bit of cork, but others use different materials: As an aside, a word of caution about using IR thermometers when trying to gauge metal temps. If the thermometer you mentioned is a kitchen thermometer, then it's going to give incorrect readings if you use it on metal. I found this out by trying to measure the temp of my ski waxing iron using my kitchen thermometer. The reason is that the thermometer calculates the temp by measuring the amount of IR radiation that the hot surface gives off. The amount of radiation is governed by two things - it's temperature, and also the type of material. Since these devices are designed to be used in the kitchen, they assume what they are measuring is food. Turns out that food, like most organic substances, radiates a lot more heat than metal at the same temperature. So in my case, when I pointed my thermometer at the hot metal bottom of my waxing iron, the probe significantly underestimated it's temperature because it just wasn't seeing that much radiation. Couldn't figure out why the wax was smoking so much at such a low temperature reading. I happened to mention it to a thermal engineer where I was working, and he explained it all to me. The skis escaped injury.
Well damn...didnt know that about the IR thermometer @PWDolkas . I am using a klein type (orange body) that is used for measuring engine temperature by shooing a red dot at it and seeing what it says. I think I am going to test it. Boil a pot of water in a steel pot and read the variance between the pot and the water...see if there is a remarkable difference. Cool idea with the cork. I was contemplating something similar but didnt get around to it. I have a Primus 71 (in a primus marked optimus blue box) that chatters completely different but nothing scary there either. I just dont know the Svea too well as it being a first for me, so just like knowing all the ins and outs before taking it to the woods haha. So I can handle the tank after (not too hot) and also know that the burner can be a red color and be perfectly normal. I guess I am just not finding definitive information that says what temp the tank can get to. I also know when the tank is hot you can hear the fuel bubbling...normal there. I guess I am just trying to avoid an "oh shit" and see fire everywhere because I ran 4 small kettles of water on it.
When the SRV vents, it is only a small, short flame when vapors hit the flame in the burner, not a flame thrower flame. Duane
If your device is designed to measure metal, like an engine, then you're good to go. I was thinking it was a kitchen thermometer. Oh, also, I would attach the key chain to the windscreen, and not the stove itself. Saves you from having to thread the key through the opening. -Paul p.s. I like the felt. That is another good idea.
I’m curious about measuring. What does it tell you? A number…but is it good or bad? What is the reference point?
I have heard a temperature of 50 in the past and really you would have to abuse a 123 to get that hot. Ive had a full 8 pint billy on mine many times and boiled at full noise. Biggest issue there is the pot sways quite violently when boiling. Never opened a srv. Its more an issue in the box stoves. Ive seen 8rs open and the normal fix was to remove the pot and run full noise for a few minutes. I have a Radius 42 stove in my collection that opened in a hut for the original owner. Description was small flame that built over a few seconds to about a meter long. They had been simmering so just turned it up and the flame went away. That srv is the only one Ive pulled apart and it is all fine and original. Dont put a heat shield around a 123 unless in extreme wind or cold and you will not open the srv
@PWDolkas ok... Yeah I think it's working... The boiling water and the side of the pot are a degree off from each other... So it's reading right. Yeah...I don't like priming it because the denatured alcohol leaves a mark on the tank and burns quickly. I wrapped carbon felt around a piece of metal from a fuel can and bent it around the burner...it increased the burn time and seems to warm the stove better outdoors. Once the stove is running I just let it go and it does not seem to be bothered by the wind too much @geeves ahhh ok 50 then! Perfect. I can't get mind to get past 34c so it sounds like I'm good to go
The SRV lets go due to pressure, not heat. I don't have near the experience some of these folks do, but like them, I have never seen a SRV vent
I attach an MSR universal canister stand to the bottom of my 123. It’s a tight fit but does very much stabilise the whole stove and pan. There’s still a bit of a jiggle with a vigorous boil, but it ain’t going to fall over.
yes, heat can increase pressure. But the SRV doesn't care what the temperature is, it opens due to pressure. It was set at the factory to open a certain pressure.
@geeves no...I just have some carbon felt on it to help preheat...it's a small piece around the burner stem (whatever you would call that) and after 1 kettle of water (gsi kettleist) I can hold it in my hands like a cup of coffee...4 kettles and it's too hot to hold but I can touch it for a few seconds I keep it with a medium low flame... something low enough like above a simmer...flames do not extend past the pot Example on another stove of the heat level... The burner bell is not completely glowing... Just the top
