A portable gas heater, often called a cabinet heater, holds a bottle of butane inside and heats a room with no electricity, plug or flue, so it keeps going in a power cut. Calor says a 15 kg bottle lasts around 50 hours with all three bars on and around 150 hours on one. It isn't cheaper than electric heating: at Calor's refill price, butane costs about 27p a kWh, against 26.32p for electricity at the price cap.
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The heaters on this page are sold for indoor use, as their makers direct. Camping and patio heaters are made for outdoor use.
Calor's rule of thumb for a 15 kg butane bottle in a typical three-bar cabinet heater: "around 50 hours of constant heat with all three bars working", and "around 150 hours" on one bar. Flogas says a typical cabinet heater takes about 118 hours to use a 13 kg bottle on its lowest setting. Worked out from each heater's published gas use at full output:
| Heater | Gas use | Hours | Cost an hour |
|---|---|---|---|
| Super Heat F180B 4.2kW portable gas heater | 315 g an hour at 4.2 kW | about 48 | £1.19 |
| Calor Manhattan 3.4kW portable gas heater | 245 g an hour at 3.4 kW | about 61 | £0.92 |
| Calor Provence 3kW stove-style portable gas heater, matt black | 245 g an hour at 3 kW | about 61 | £0.92 |
| Super Heat 3kW catalytic portable gas heater | 214 g an hour at 3 kW | about 70 | £0.81 |
Our arithmetic from the gas use on each heater's Calor listing, at Calor's suggested price of £56.50 for a 15 kg refill on 4 November 2026, before its volatility surcharge. On a lower setting a bottle lasts much longer. The F180B's listing says "60 hours on high", which doesn't match its own figure of 315 g an hour; its manual gives 305 g.
No, not with bottled gas. Butane holds about 13.7 kWh per kilo (Calor's figure), so at £3.77 a kilo it costs about 27p for each kWh of heat, close to electricity's 26.32p at the price cap. Mains gas central heating is much cheaper, at 7.97p a kWh. A portable gas heater earns its place when the electricity is off. The cheapest way to heat a room.
You buy the first bottle with a refill agreement, then swap empties for full ones. Calor's suggested prices: a 15 kg butane refill £56.50, or £106.49 for your first bottle including the £49.99 agreement. Flogas sells 13 kg butane for £56.69, plus a £47.50 cylinder charge if you have no empty to return. Prices vary between stockists, and both add a volatility charge.
All four are butane heaters for indoor use, sold by Calor's own appliance shop. None includes a gas cylinder.
Prices checked 4 November 2026, including VAT.
A traditional radiant cabinet heater with three settings and push-button ignition. It's the cheapest and most powerful of the three, and it needs the biggest room.
A flame-effect cabinet heater at 17 kg, for a smaller room than the F180B. There's no thermostat, and the ignition uses a battery.
Looks like a small wood stove and costs the most. At 34 kg it's heavy to move, even on its wheels. This is the gas-only Provence; a separate hybrid model is sold too.
A light catalytic heater, 9 kg, with three settings up to 3 kW. It burns the least gas an hour of these, about 70 hours from a 15 kg bottle at full output, and needs the same room size as the F180B.