Propane heat
Best Indoor-Safe Propane Heaters
Propane is the fastest, cheapest way to put real heat into a tent, cabin, or camper. The trick is buying a heater built for indoor use, with an oxygen sensor and a tip-over shutoff, and then running it the right way: fresh air in, a CO alarm watching the room. Below are our top indoor-safe picks plus the buying logic and safety rules that keep this kind of heat from becoming a hazard.
Quick picks
Short on time? Start here
Mr. Heater Portable Buddy
Fast, simple, indoor-safe radiant heat for most people.
Mr. Heater Big Buddy
A fan and three heat levels for cabins and large tents.
Camco Olympian Wave-6
Silent catalytic warmth you can mount on a wall.
At a glance
How the heaters compare
| Heater | Best for | Output | Heats up to |
|---|---|---|---|
| Mr. Heater Portable Buddy | Most people | 4,000 to 9,000 BTU | 225 sq ft |
| Mr. Heater Big Buddy | Larger rooms | Up to 18,000 BTU | 450 sq ft |
| Camco Olympian Wave-6 | Quiet RV heat | 3,200 to 6,000 BTU | 230 sq ft |
| Camco Olympian Wave-8 | Larger RVs | 4,200 to 8,000 BTU | 290 sq ft |
| Kidde CO Alarm | Safety pairing | Detector, not a heater | Any space |
The picks in detail
Our top indoor-safe propane heaters
Mr. Heater MH9BX Portable Buddy
Output: 4,000 to 9,000 BTUHeats: Up to 225 sq ftSafety: ODS + tip-over shutoff
The Portable Buddy is the default pick for good reason. It is the most popular indoor propane heater in North America, and it earns that with fast radiant heat, an oxygen depletion sensor, a tip-over shutoff, and dead-simple one-cylinder operation. It runs about three hours on high or five and a half on low from a single 1 pound cylinder, and you can hook it to a 20 pound tank with a hose and filter for far cheaper hours. For a tent, ice shanty, truck, or small cabin, this is the easy answer.
What we like
- True indoor-safe design with an oxygen sensor
- Fast directional radiant heat
- Cheap to buy and simple to run
Worth knowing
- 1 pound cylinders get expensive fast
- Radiant heat warms a direction, not a whole room
Mr. Heater MH18B Big Buddy
Output: 4,000 / 9,000 / 18,000 BTUHeats: Up to 450 sq ftExtra: Built-in blower fan
When one Buddy cannot keep up, the Big Buddy steps in. Three heat levels and a built-in fan push warmth across a real room, so it handles larger cabins, big tents, and workshops up to about 450 square feet. It runs on two 1 pound cylinders or a 20 pound tank by hose, up to roughly eleven hours on the dual setup. The same oxygen sensor and tip-over shutoff carry over. The fan needs four D batteries or an optional AC adapter, which is the only real catch.
What we like
- Fan spreads heat across a whole room
- Three output levels for any space
- Same indoor-safe sensors as the small Buddy
Worth knowing
- Bigger, heavier, and will short-cycle in a tiny space
- Fan needs batteries or an adapter
Camco Olympian Wave-6 Catalytic Heater
Output: 3,200 to 6,000 BTUHeats: Up to 230 sq ftType: Flameless catalytic
The Wave-6 is the pick when you want silent, even warmth you can mount on a wall. Catalytic heating is flameless and close to fully efficient, so it sips fuel and makes no fan noise at all. It runs off an RV propane line or a 1 pound cylinder with an adapter, and it mounts on a wall to save floor space. It warms slower than a radiant Buddy and costs more, but for an RV, van, or sailboat where quiet matters, nothing beats it.
What we like
- Completely silent, no fan or electricity
- Very efficient, even radiant warmth
- Wall-mountable to free up floor space
Worth knowing
- Slower to warm a space than a radiant heater
- Needs a mounting bracket or cylinder adapter
Camco Olympian Wave-8 Catalytic Heater
Output: 4,200 to 8,000 BTUHeats: Up to 290 sq ftType: Flameless catalytic
The Wave-8 is simply the bigger brother of the Wave-6, with more output for larger RVs and cabins while staying just as quiet. Same flameless catalytic tech, same wall-mount or portable setup, more heat for a bigger box. If the Wave-6 would leave you cold in a fifth-wheel or a roomier cabin, this is the one to size up to. Run it on its lower setting most of the time and crack a vent, since more output means more oxygen used.
What we like
- More output while staying silent and efficient
- Portable or wall-mounted
- Great for larger RVs and cabins
Worth knowing
- Uses more oxygen at full output
- Same accessory needs as the Wave-6
Kidde Battery-Powered Carbon Monoxide Alarm KN-COB-B-LP2
Power: AA batteriesSensing: Checks air every 15 secWhy: The mandatory companion
This is not optional gear, it is part of the heater. Any propane heater can produce carbon monoxide, and the oxygen sensor built into a Buddy does not detect CO. This battery Kidde alarm watches the air every fifteen seconds with an electrochemical sensor and keeps working off-grid because it needs no shore power. Mount one near where you sleep. For a permanent RV install, a dedicated RV-listed CO and propane alarm is worth adding, but everyone running a flame needs at least this.
What we like
- Battery-powered, so it works fully off-grid
- Fast electrochemical CO sensing
- Cheap insurance against the one real danger
Worth knowing
- Not listed for permanent RV mounting
- Sensor lasts about seven years, then replace it
How to buy an indoor-safe propane heater
Start by confirming the heater is actually built for indoor use. The phrase you are looking for is an oxygen depletion sensor, often shortened to ODS, paired with a tip-over shutoff. The ODS cuts the gas if oxygen in the room runs low, and the tip-over switch kills it if the heater falls. Outdoor-only patio heaters skip both and have no business inside a tent or van. Every heater above has them, but if you shop elsewhere, do not assume, check.
Next, size the BTU output to your space rather than buying the biggest unit you can. A 9,000 BTU Portable Buddy is plenty for a tent, truck cab, or small cabin room around 200 square feet. Step up to the Big Buddy's 18,000 BTU only when you are heating a real room, because an oversized heater in a tiny space just burns through fuel and oxygen faster while you crack the window wider to compensate. Matching output to the room is how you stay both warm and safe.
Then think about your fuel supply before you buy. The 1 pound disposable cylinders are convenient but expensive over a season, so plan to add a hose and filter that lets you run from a refillable 20 pound tank kept outside or in a vented bay. That single accessory turns a pricey-to-run heater into a cheap one. Catalytic units like the Olympian Wave can also tap an RV's existing propane line, which is the tidiest setup of all if you have one.
Finally, decide between radiant and catalytic based on how you will use the heat. Radiant Buddy heaters warm fast and in a direction, ideal for quick heat you turn on and off. Catalytic Wave heaters are silent, run without electricity, and mount on a wall for steady background warmth, which suits an RV or sailboat. Neither is set-and-forget overnight heat. Both want fresh air and a CO alarm, every single time.
Frequently Asked Questions
Is it safe to run a propane heater indoors while sleeping?
Not in a sealed space. Indoor-safe heaters with an oxygen sensor are rated for occupied indoor use with ventilation, but the safest habit is to warm the space before bed, shut the heater off to sleep, or only run it with a cracked vent and a working CO alarm nearby. Both radiant and catalytic propane heaters also add a lot of water vapor to the air, which causes condensation, and they consume oxygen as they burn. Treat them as supervised heat, not set-and-forget overnight heat.
What does the oxygen depletion sensor actually do?
The oxygen depletion sensor, or ODS, shuts the heater off if the oxygen in the room drops below roughly 18 percent. It is a safeguard against suffocation and the incomplete combustion that follows when oxygen runs low. The key thing to understand is that it is not a carbon monoxide detector. It watches oxygen, not CO, so you still need a separate carbon monoxide alarm in the room. Every heater on this list except the alarm itself has an ODS.
How much ventilation does a propane heater need?
A common rule of thumb is at least one square inch of fresh-air opening for every 1,000 BTU per hour the heater puts out. A 9,000 BTU Portable Buddy wants roughly a nine square inch crack in a window or vent, and an 18,000 BTU Big Buddy about double that. The point is to let fresh air in and combustion byproducts out. Cracking a roof vent and a low window creates good cross-flow without losing much heat.
How long does a 1 pound propane cylinder last?
Plan on about three hours on high and five to six hours on low for a 9,000 BTU Portable Buddy. That adds up quickly if you heat every night, which is why many people connect a 20 pound tank with a hose and filter instead. The bigger tank costs far less per hour and means fewer trips to refill. If you go that route, keep the tank outside or in a vented compartment, never sealed inside the living space.
Radiant or catalytic propane for a van or RV?
Radiant heaters like the Buddy series warm fast and in a direction, which is great for quick heat in a tent or truck. Catalytic heaters like the Olympian Wave run silent, need no electricity, mount on a wall, and give steady even warmth, which suits an RV with a built-in propane line. Both need ventilation and a CO alarm. If quiet and a tidy install matter most, go catalytic. If instant heat and low cost matter most, go radiant.