MSR stoves Reactor..experiences? worth it?

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just saw that MSR came out with an even bigger size cannister..might make the Reactor even more stable
 
Can anyone confirm the stories of the Reactor having a safety shutoff that can't be reset by the user? It sounds like it could be a serious problem under the wrong circumstance.

Yes. If the burner unit overheats (its underside is actually plastic), it shuts off the fuel inlet flow permanently, pending returning the unit for service. This was a concern of mine as well, until I observed first hand how cool the unit's underside stays at the same time as its topside radiates searing heat upward, trademark red-hot MSR-logo'd glow and all. As long as you're allowing the stove and Reactor-compatible pot to ventilate freely, I just can't see this happening--simply put, the heat just goes up. The only ambient temperature limit my manual specifies is 120F for the fuel canisters.

Well, there is one other way to mess up and overheat the unit, which the instructions do caution against: trying to light the plastic underside of the head rather than the top from whence the gas emerges. Since it's obvious that the gas comes out of the top, it's hard to see how anyone with common sense and even the most minimal exposure to gas stoves of any sort would even think of doing that. And if someone does do that, imo it's probably a good thing that the stove prohibits further attempts at use until remedial education can take place and any heat damage can be addressed.

Pretty much what he said word for word. But add bulky to list as well.

The Reactor really isn't materially more bulky than other integrated stove/pot systems of comparable pot capacity (Reactor pots come in 1.0, 1.7, or 2.5L sizes). However, it is a few ounces heavier and (fairly, IMO, in light of the differential in performance and ruggedness) a little more expensive. The "bulky" rep stems from the fact that the Reactor was initially released in the 1.7L size, which made it bulkier than the 1L JetBoil. Now you can choose whichever pot size best meets your needs.

just saw that MSR came out with an even bigger size cannister..might make the Reactor even more stable

Personally, I wouldn't tote the extra large canisters unless my trip is long and/or the group is large because of the volume and weight inefficiency on a subsequent trip of starting off with a huge, partially full canister--remember, a single 8-oz canister (now the 'medium' size) unleashes 1hr:20min of burn time. If I think I'll need improved stability where I'm headed, my choice would be to include a canister stand on my gear list.

Alex

PS FYI, the product site has lots of additional useful info.
 
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I had a fairly large group on a backpacking trip over the weekend and some folks needed to borrow my stove, so I had the opportunity to compare my Whisperlite (equiped with copper heat exchanger and foil wind screen) side by side to my new Reactor.

Bottom line, I'd estimate that the Reactor melted snow and heated it to boiling at a rate roughly twice that of my Whisperlite. It was comical how fast the Reactor was. This was after the Whisperlite had been primed and was heating at max output; similarly, I had the Reactor fuel canister sitting in a small bowl of tepid water to keep the canister warm. I considered this to be the best apples-to-apples comparison.

Some other details:
  • I had similar sized pots on both stoves: the 1.7 L on the Reactor, and something close to that on the Whisperlite. I simply compared the rates of output, the output being 1L Nalgene bottles filled with boiling water.
  • I got maybe 10-12 L out of my 8 oz Reactor canister. That's similar to my estimates for what I normally get out of my Whisperlite, but I didn't try to compare fuel efficiency this time, just speed. I'd guess the Reactor does a little better on fuel efficiency, but I'm not sure how much better.
  • It was warm out, probably 20 degrees F. So you'd get slightly less production if it was cold. That would also be true of the Whisperlite.
Some asides that are worth remembering but aren't related to the Reactor vs. Whisperlite comparison:
  • Most of the heat needed to boil snow is used to 1) melt the snow; and 2) heat that water to boiling. Simply warming up cold snow doesn't use much energy. So I'd expect the Reactor's production to be similar, within 10%, even if it was quite cold out.
  • Now, if you could find a source of liquid water, you could double your production, both in terms of liters produced per oz fuel, and in terms of time required to produce each liter. That's something to think about.
  • For those of you who like numbers: heating 1 kg of snow from -25 C to 0 C requires 51 KJ of energy; melting 1 kg of snow to water (no temperature change - temp stays at 0 C) requires 334 KJ; heating 1 kg water from 0 C to boiling requires 418 KJ.
 
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I'd estimate that the Reactor melted snow and heated it to boiling at a rate roughly twice that of my Whisperlite. It was comical how fast the Reactor was.

I know what you mean by how comical the difference is in boiling time between the WhisperLite and the Reactor. It's made even funnier because at the same time as you're watching the two stoves work on their respective liters of water, eager to get your meal going, you're witnessing the angry roar of the WhisperLite (how 'whisper' ever made it into that name is a mystery to me - does anyone know the answer?) side-by-side with the quiet purr of the Reactor. The time you get the biggest sense of 'angry' from the Reactor is when you lift the pot and feel the searing heat being radiated from the bright red MSR logo-glowing burner head.

Some asides . . .
  • Most of the heat needed to boil snow is used to 1) melt the snow; and 2) heat that water to boiling. Simply warming up cold snow doesn't use much energy. So I'd expect the Reactor's production to be similar, within 10%, even if it was quite cold out.
  • Now, if you could find a source of liquid water, you could double your production, both in terms of liters produced per oz fuel, and in terms of time required to produce each liter. That's something to think about.
  • For those of you who like numbers: heating 1 kg of snow from -25 C to 0 C requires 51 KJ of energy; melting 1 kg of snow to water (no temperature change - temp stays at 0 C) requires 334 KJ; heating 1 kg water from 0 C to boiling requires 418 KJ.

Some thoughts on these.

When it gets really cold, I wouldn't discount the convective heat loss from the sides of the pot, though I haven't done careful enough testing to determine whether your 10% number covers it. Even some very basic insulation and/or shielding (e.g., a la JetBoil) can make a substantial difference in the convection coefficient. Using your calorie numbers and some linear math, boiling 1kg of snow from 0F should require 2.5 times the 3-minute time claimed by MSR for boiling water at 70 degrees F, or 7.5 minutes at standard pressure. Next time I have the chance in zero degree temps, I'll measure the delta between the expected and actual times, while playing with wind and shielding/insulation. My guess is that 7.5 minutes won't get me to a boil without it, especially in wind. None of this to detract from the Reactor's exceptional resistance to wind vs. any other stove -- the only wind effect I'm thinking about is the convective loss from the pot.

To generalize a bit on your 2nd aside: the warmer the water you start with, the faster (and hence with less fuel consumption) you'll be able to boil it. The state change is merely a non-linearity (quantified in your 3rd aside) in light of which the simple generalization still holds true. And if you do find a source of liquid water such as an under-snow stream, you can save even *more* fuel if you're fortunate enough to have an above-freezing place such as a warm cabin in which you can filter or treat the water vs. boiling it at all for applications that don't require hard boiling, such as drinking water.


Brian, congrats on your acquisition - may it bring you backpack after happy backpack of comically fast boiling speeds!

Alex
 
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I will point the major caveats with any butane mix stove. The capability of the fuel canister to vaporize fuel reduces as the temperature goes down. Different companies supply different mixes of fuels so cold weather response can vary. In cold conditions the more volatile fuel components preferentially discharge out through the burner as the stove operates thus as the fuel canister empties, the cold weather vaporization drops and the stove can lose performance. In my experience with the MSR fuel the difference in boil time was substantial between full and near empty in cold conditions. I once had to use coleman brand and it easily had to be 10 degrees warmer for the stove to run right

Cold weather expansion of liquid fuel impacts whisperlights oddly. In very cold conditions the stove can radiate enough heat into the surrounding snow to raise the humidity in the air near the fuel nozzle. As the fuel leaves the nozzle it cools and in the right conditions, ice will form at the fuel nozzle restricting the burner output. The stove runs but at a much lower burner output. Generally if the stove is on an open surface with no snow, the humidity in the air is rapidly dissipated. I have only seen this issue in sub zero conditions. This can also happen when a pot has snow on it when put on the hot burner.

I have had remarkable luck with a hanging pot shield on a Pocket Rocket that encircles the pot with about 1/2" of air gap. The shield hangs below the pot bottom but ends roughly above the fuel valve so there is minimal heat reflected back toward the tank. I find that it allows the stove to operate in breezy conditions and fuel usage is lower. I have seen a consistent 30% decrease in fuel usage for 3 seasons usage.


I believe there was predecessor to the whisperlight that was even louder than a whisperlight. Compared to a dragonfly or XGK the whisperlight is quiet.
 
To generalize a bit on your 2nd aside: the warmer the water you start with, the faster (and hence with less fuel consumption) you'll be able to boil it. The state change is merely a non-linearity
But it's more than a mere non-linearity. My point is that approximately half of the required energy is used just for the state change.

In other words, it will take about twice as much energy to heat SNOW from 32 F to boiling as it will to heat WATER from the same temperature (32 F) to boiling. The state change uses a crap ton of energy.

Most people don't realize that the act of simply melting snow, without actually changing its temperature, requires (a lot of) energy. I hadn't done the math before and was actually a bit surprised it was so much, which is why I shared.

Anyway, I started another thread if we want to hash it out further regarding the thermodynamics. It's a great purchase so far.

Peakbagger, all of the points in your first paragraph are true and well taken. To get around that problem, as Alex suggested I simply placed the canister in a small collapsable bowl filled with tepid water, which I changed out once or twice over the course of the hour or so I had it working. The performance of the stove didn't appear to change over the course of the entire canister, probably because the canister was always warm, between 40-80 degrees, I'd estimate.

Also, Alex I think it's the Dragonfly that's loud, not the Whisperlite. My Whisperlite, at least, really does whisper. I find the gentle hiss quite soothing, but I find myself wanting to poke sporks in my eyes when I have to listen to the Dragonfly.
 
Alex I think it's the Dragonfly that's loud, not the Whisperlite. My Whisperlite, at least, really does whisper. I find the gentle hiss quite soothing, but I find myself wanting to poke sporks in my eyes when I have to listen to the Dragonfly.

Perhaps there are different generations of WhisperLite? I know that among at least some hikers, the stove has 'earned' the moniker 'WhisperLOUD'. I've always been in the upright isobutene camp, and can't remember with absolute certainty whose roars were how loud -- I do know that they've included the WhisperLite and Dragonfly. I'm not sure whether or not I've heard an XGK. Perhaps the explanation is as simple as that there's loud and very loud -- one man's gentle hiss may be another's angry roar.

Brian, don't use your sporks that way -- in the cold, they're especially brittle!

Alex
 
Ha!! You know, one other factor that hasn't come up in the comparison conversation is the Whisperlite shut down smell. Again, don't get me wrong, my Whisperlite has provided me with so much pleasure over the past 20 years at least, I hesitate to speak poorly of that little stove in any context. But if I move to the Reactor exclusively for winter, and I suspect I will, I won't miss the smell of the last bits of white gas half-burning and vaporizing as the stove cools. Man, that smell is horrible, especially when the stove is in your tent vestibule.
 
Specific to the whisperlight shut down. Blow out the flame rather than letting it burn. If will cut way down on burner fouling and soot.
 
I will point the major caveats with any butane mix stove. The capability of the fuel canister to vaporize fuel reduces as the temperature goes down. Different companies supply different mixes of fuels so cold weather response can vary.

Manufacturers do improve winter performance by putting a mixture of light and heavy molecules (different butane/propane carbon chains) in a gas canister.

I cannot cite a reference, but I believe that there is a fundamental problem with these "mixed gases". Just using the stove once on a winter day burns most of the molecules which are very good at burning in the cold. (have the highest vapor pressure). So after one use, the canister cannot perform well in the future in the same conditions, even if plenty of gas remains.

I would be interested in hearing from anyone who can substantiate or refute this.
 
I can not cite rigorous documentation of the differential vaporization but used to have to plan for it during my close to annual spring time section hikes. The new full tanks worked down near freezing but as the tank emptied, I had to adopt the approach of keeping it warm before firing and then occasionally rewarming it with my hands while cooking or full open throttle would end up darn close to a bic lighter's output. Its not linear, the performance is pretty steady and then it starts to degrade rapidly. It depends on how high you turn up the burner. My typical use is run the burner hot to heat the water to boiling and then turn it way down for simmering. If I wanted to drag out my old textbooks I expect partial pressures factors in.

Most weekenders carry full canister's and rarely do they run them to empty. I expect many folks either throw away half full canisters so they don't need to deal with running out for a two or three day trip. It was pretty predictable when sectioning the AT that hiker boxes in resupply towns would have a small collection of half full or less canisters as most folks did not want walk out of town with a less than full tank so they wouldn't have to carry the empties out. I ran into more than few folks on budgets that planned on mostly empty cylinders in hiker boxes. Unfortunately the evil side of canister stoves is the waste per btu ratio, the canisters are rarely recycled and in most cases end up in a landfill. There is a device for punching a hole in them to make them recyclable but few folks worry about it. There are devices sold on line on occasion for refilling them off a bulk tank but the canisters are not designed for this use and technically its illegal to refill them although I expect the main issue is if someone tried to do this commercially.
 
To overcome this problem, I kept the fuel canister warm (between 40-80 F) for the duration of use on this most recent trip by keeping it in a warm water bath. At that temperature, both propane and isobutane are firmly in the gas phase. To add experimental evidence, I ran completely through my canister on this trip (large group) and did not notice ANY change in performance over the course of use. I punctured it with a screwdriver and hammer when I got home and recycled it.
 
To overcome this problem, I kept the fuel canister warm (between 40-80 F) for the duration of use on this most recent trip by keeping it in a warm water bath. At that temperature, both propane and isobutane are firmly in the gas phase. To add experimental evidence, I ran completely through my canister on this trip (large group) and did not notice ANY change in performance over the course of use. I punctured it with a screwdriver and hammer when I got home and recycled it.

OK, so you can get the canister stove to run long enough without a bath to warm the bath water?
 
OK, so you can get the canister stove to run long enough without a bath to warm the bath water?

The answer to your question is yes. For the time it takes to warm new water, *any* liquid water will do (32 degrees is plenty warm for the isobutane). Typically there'd be at least a few ounces in peoples' bottles, and/or a stream source. If your group has no liquid water at the ready, then all you need to do is stick the canister inside your jacket for a few minutes to warm it up. The stove will then run fine for a few minutes before the canister again gets too cold.

Alex
 
What Alex said. Also, the bowl I have fits the regular 8 oz canister pretty well, so maybe 2-3 oz of liquid water is all that is needed to keep the canister warm. I can't recall ever having gotten to camp and not had at least that much water left, but if that did happen, it would be trivial to warm the canister enough in your jacket to get it started and melt 2-3 oz of snow. I'm in the habit anyway of preserving a little bit of liquid water to get the snow melting properly and prevent scorching the pot, which happens if you try to start with snow instead of slush. So I don't really have to change my habits.

I've got a couple of pretty difficult trips coming up, and I'll have the chance to really test the system on those trips. But I'm confident enough with the Reactor that I won't be bringing my Whisperlite as backup. Though we will have at least one of them among the group.

The only downside I see with switching to the Reactor is that my years of practice and resultant mad skills with my Whisperlite are likely to atrophy. I mean, I think I could get that stove going with my eyes closed. I can just listen to the priming process, know when the priming cup is half full, and almost feel the exact right time to goose the fuel valve after it's primed. I'm going to miss you, old pal.
 
The answer to your question is yes. For the time it takes to warm new water, *any* liquid water will do (32 degrees is plenty warm for the isobutane). Typically there'd be at least a few ounces in peoples' bottles, and/or a stream source. If your group has no liquid water at the ready, then all you need to do is stick the canister inside your jacket for a few minutes to warm it up. The stove will then run fine for a few minutes before the canister again gets too cold.

Alex

Well this weekend should provide a good opportunity to experiment at a camp site.... I only have a pocket rocket stove.
 
Definitely worth the experiment to see if you can get it lit. But realize that the performance of the Reactor will be superior to the Pocket Rocket because of the design of the burner (less susceptible to wind) and the pot (captures heat more efficiently). I don't think the Pocket Rocket would be a good stove for an overnight trip, but it's great as emergency gear, again provided you have a way to keep the canister warm. I take my pocket rocket as emergency gear in the winter, but I (now) use the Reactor for backpacks.
 
I've been following this thread and now that it seems to be winding down I thought I'd jump in with some of my new guy, stupid questions. I have never used a stove in Winter conditions and from the reading I have been doing there sounds like a lot of considerations for successful operation versus warm conditions.

I own a Jetboil Sumo 1.7L stove that has a variable control burner and at least on the spec page says it can be used to melt snow. I don't see the Jetboil brand mentioned much in Winter stove threads. Is there an issue with the stove or the Jetboil fuel in cold conditions? Do you literally walk around with the fuel canister in your jacket pocket all day (sounds dangerous in a fall)? Where do you get a "water bath" from if you're melting snow for water?

If anyone could expand on this topic or point me in the direction of a thread that is more beginner oriented it would be appreciated. Thanks.
 
If you are warm, putting a canister inside you jacket will warm it up in few minutes. If you are in survival situation where you need heat now and your core is chilled it may be more difficult to warm up. In general it comes down your definition of winter conditions, in moderate winter conditions 20 F and above canister stoves work well with the exception of the full versus empty derate but if you get into temps as forecast this weekend, below zero and windy I expect that liquid fuel is the way to go. The nice thing with canister stoves are they are simple to set up and get going. A whisper light is far more complex and that's where the older peak one white gas stoves work well as they don't require setup and also don't suffer lack of maintenance issues like a whisperligh can.

I cannot comment on jet boil fuel or the stoves as I haven't dealt with them. They owned the market for few years and the Reactor appears to have been designed to give MSR a competitor.
 
If you are warm, putting a canister inside you jacket will warm it up in few minutes. If you are in survival situation where you need heat now and your core is chilled it may be more difficult to warm up. In general it comes down your definition of winter conditions, in moderate winter conditions 20 F and above canister stoves work well with the exception of the full versus empty derate but if you get into temps as forecast this weekend, below zero and windy I expect that liquid fuel is the way to go. The nice thing with canister stoves are they are simple to set up and get going. A whisper light is far more complex and that's where the older peak one white gas stoves work well as they don't require setup and also don't suffer lack of maintenance issues like a whisperligh can.

I cannot comment on jet boil fuel or the stoves as I haven't dealt with them. They owned the market for few years and the Reactor appears to have been designed to give MSR a competitor.

They look very similar. That is why I was curious why no one appears to use the Jetboils in Winter versus MSR models. For my purposes, "Winter" conditions would be 0 deg F and above.
 
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