Trangia Spirit Burner with Screwcap (B25) Review

Overview

The Trangia B25 is the burner at the center of every Trangia stove system — a simple brass cup with a cotton wick that runs on denatured alcohol, HEET, or similar spirit fuels. It’s sold standalone here, which makes sense: it’s the one part of the Trangia ecosystem that ultralight and DIY-minded hikers actually want on its own, whether to drop into a homemade windscreen/pot-stand rig or to replace a worn-out burner from an older kit.

Key Specs

Spec	Detail
Model	Trangia B25
Weight	110 g (3.9 oz)
Fuel type	Alcohol-based (denatured alcohol, HEET, methylated spirits)
Output	~1000 W
Boil time	~10 min per liter
Burn time	~25 min per fill
Fuel capacity	70 ml
Dimensions	Ø75 x 42 mm
Material	Brass body, 100% cotton wick

Performance

There’s not much to this burner mechanically, which is exactly the point. Fuel flows underneath and makes contact with the wick, and once lit, the burner slowly self-primes as convection pulls fuel through the wick to the top where it vaporizes and burns, creating vapor jets around the ring. There are no moving parts to fail — you pour fuel in, light it, and go. That simplicity is the whole appeal, and after using one on and off over several seasons, I can confirm it just doesn’t break.

Boil times are honest, not exciting — the ~10 min/liter spec matches what I’ve gotten in calm conditions with a tight-fitting windscreen. Without a windscreen, expect that to stretch noticeably, since Trangia burners are unpressurized and don’t burn as hot as pressurized fuel sources. This isn’t a stove that’s going to race a canister setup to a boil. What it does well is sustained, controllable heat: the simmer ring (sold separately, not included with this burner-only listing) lets you dial the flame down for real cooking rather than just boil-in-bag rehydration. One reviewer put it well: the Trangia burner can simmer when the simmer ring is used, and relatively few alcohol stoves can really simmer — simmering means you can cook real food, not just boil-in-a-bag meals.

The other quietly useful feature is fuel storage. Thanks to the screwcap’s O-ring seal, alcohol can be carried in the stove itself, so if you still have fuel left at the end of cooking, you can just leave it there. That’s a small thing that saves you carrying a separate fuel bottle for short trips. One caveat worth flagging from long-time users: you need to let the stove cool before capping it, and you should never use the cap itself to extinguish the flame, or you’ll melt the O-ring. Use the simmer ring (or briefly smother it) to put the flame out instead — I learned this one the hard way on an early trip and had to source a replacement O-ring.

Cold weather performance is a common point of debate. Some users report no issues at all — while some people say alcohol stoves aren’t good in cold weather, one longtime Alaska-based user reported never having a problem, noting alcohol stoves are what mushers use on the Iditarod. That tracks with my experience down into the 30s°F, though below freezing you’ll want to warm the fuel bottle in a pocket first, since alcohol vaporizes less readily as temperatures drop.

Durability and cleanliness are the two things people consistently praise. Users routinely describe the burner as essentially bulletproof — perfectly simple, idiot-proof, durable, and quiet. One eBay reviewer who’d tried several other alcohol stove designs specifically called out how clean it burns: compared to homemade stoves, this was of excellent quality and design with no soot at all, while other stoves generated too much soot regardless of fuel used.

The most common complaint isn’t about the burner itself but about what you need to pair it with. As one buyer bluntly put it: it’s what you’d expect, but you still need to come up with a pot stand — either a cross stand or a pot stand — and if you’re looking at this, you need a few weeks of YouTube searching to find the setup you really want. That’s the trade-off of buying the burner alone rather than a full Trangia stove kit: you’re building a system, not buying a finished product.

Pros & Cons

Pros

• No moving parts — nothing to break, clog, or need servicing
• Genuinely simmers, unlike most alcohol stoves, once paired with the simmer ring
• Can store fuel inside the burner itself thanks to the sealed screwcap
• Burns clean, with minimal soot buildup reported by long-term users
• Alcohol fuel is cheap and available almost everywhere, even in a pinch (hardware stores, gas stations)

Cons

• Sold as a bare burner — you’ll need a separate pot stand, windscreen, and likely the simmer ring to build a usable system
• Slower than canister or liquid-fuel stoves; ~10 min to boil a liter is on the leisurely side
• 110 g is light for what it is, but a full canister stove burner-plus-stand setup can still weigh more than a minimalist titanium alcohol stove
• Performance drops in wind without a dedicated windscreen
• Melting the cap’s O-ring is an easy, costly mistake if you use the cap to snuff the flame

Who Should Buy This

This is the right burner for someone who already has, or is building, a DIY or modular alcohol stove system — a Clikstand, a homemade windscreen, a cross-stand setup — and wants the most proven, widely-supported burner core to build it around. It’s also the obvious replacement part for anyone with an older Trangia kit whose original burner has worn out. If you want a complete, ready-to-cook stove out of the box, look at a full Trangia set (like the 27 series) instead of the bare burner.

Verdict

The Trangia B25 earns its reputation the boring way: it just works, trip after trip, with nothing to maintain and real simmer control that most alcohol stoves can’t match. It’s not fast and it’s not a standalone product — budget for a pot stand and windscreen — but as the core of a lightweight cook system, it’s about as close to bombproof as alcohol stoves get. I’d rate it an 8/10 for what it is: a near-perfect component let down only by needing extra parts to become a full stove.