Manhattan Gas Heater Review: The Calor Gas Heater Built for Safety

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When the power goes off in winter, most gas central heating goes off with it, because a modern boiler needs electricity to light, run its controls and pump the water round. The Manhattan gas heater doesn’t. It runs on a bottle of butane, lights with a push-button spark, and puts real flames behind glass in the corner of your living room while the rest of the street sits in the dark.

It isn’t the cheapest portable gas heater you can buy, and that’s the point. The Manhattan gas heater is sold by Calor and Flogas, two of the best-known names in UK bottled gas, and by gas dealers up and down the UK. For something that burns gas in the room where your family sits, a name you already trust is worth paying for.

Why the Manhattan Gas Heater Is Worth Paying More For

Search for an indoor gas heater and you’ll find dozens of near-identical grey cabinets from brands nobody has heard of, most of them sold with little more than a one-line description. They’re cheap for a reason, and when something goes wrong there’s nobody to ring.

The Manhattan gas heater is a different proposition. It’s made by Universal Innovations, carries a two-year guarantee with a proper factory helpline, and sits in the official ranges of the companies that fill the bottles. When Calor puts a heater in its own shop next to its own gas, it’s telling you it’s happy for its name to be on it. If you’ve ever typed “Calor gas heater” into a search box, this is the kind of heater you had in mind.

It also carries a CE mark with a notified body number on the label inside the lid. For a gas appliance, that means an independent test body has assessed it, not just that someone printed a logo on the box.

One buyer summed it up well: “Oozes quality and knocks the socks off cheaper gas heaters… You can buy cheaper models that’s for sure but you pay for what you get.” Six months later, they added that it was worth every penny.

Manhattan Gas Heater Safety Features

This is where the Manhattan gas heater earns its keep. Every one of these is built in, not an optional extra.

Oxygen depletion sensor (OxySafe). If the oxygen level in the room starts to drop, the sensor shuts the gas off before the air becomes unsafe to breathe. It’s the single most important feature on any gas heater safe for indoor use, and you should never buy one without it.

Flame supervision device. If the flame goes out for any reason, a draught, a knock or the bottle running low, the device cuts the gas. Unburnt gas can’t keep pouring into the room.

Flames behind glass. The burner and log-effect coals sit behind a closed glass door, so there’s no open flame for a sleeve, a dog’s tail or a stray tea towel to catch.

Connection under a lid. The regulator and hose sit under a hinged lid on top of the Manhattan gas heater’s cabinet, and the bottle sits in the back behind a curved metal guard. A full-size bottle does stick out at the back, so leave room behind it. The connection itself stays tucked away, rather than everything being on show as it is on the open-backed cabinet heaters, where the bottle, hose and regulator are all within reach of small hands and paws.

Safety rules printed where you need them. The lighting and safety instructions are printed on the underside of the lid, so they’re in front of you every time you change the bottle.

Is a Gas Heater Safe for Indoor Use?

A good one is, used properly. The Manhattan gas heater is designed for indoor use, but like any heater with a flame it needs respect. These rules come straight from the instructions, plus a few of our own that apply to every flame heater.

Give it a big enough room. The room needs to be at least 64 cubic metres, for example a 6m by 4.5m room with a standard 2.4m ceiling, with at least 80 square centimetres of ventilation. Trickle vents or a window open a crack will do it.

Never in the wrong room. Don’t use it in bedrooms, bathrooms, basements, high-rise flats, private garages, caravans or motorhomes.

Keep the space around it clear. Keep it at least 0.6 metres from curtains, furniture, bedding and anything else that can burn, above and beside it, and away from glass doors and windows. Stand it on a flat, solid floor. It isn’t designed to be pushed against a wall, whatever the showroom photos suggest.

Extreme care around children and pets. The glass front and the casing get hot, and the instructions say to let it cool for an hour before touching the front or sides. Keep children and pets away from it, and never leave them alone in a room with it running. If you have small children or pets, Calor sell a safety cage that fits around the heater.

Fit a carbon monoxide alarm in the same room. Any fuel-burning heater used indoors needs a working CO alarm close by. Carbon monoxide has no smell or colour, so an alarm is the only warning you’ll get.

Never leave it running unattended. Don’t light it and go to bed, and don’t leave it on when you go out. Warm the room, turn the heater off at the bottle, then let duvets and hot water bottles take the night shift.

Have it serviced. The instructions recommend a service by a competent gas engineer once a year, or after a long spell unused, and a leak check whenever it comes out of storage.

How Much Heat, and How Long Does a Bottle Last?

The Manhattan gas heater puts out 3.4kW on its top setting, with three heat settings in all. That’s plenty for a living room or a kitchen-diner, which is exactly the right size for a power cut: heat one room properly and gather everyone in it, rather than trying to warm the whole house.

At full power the Manhattan gas heater uses about 245 grams of gas an hour. Do the sum and a 15kg bottle gives you around 61 hours on maximum, which is two and a half days of heat from one bottle. A 7kg bottle gives about 28 hours. On the lower settings it lasts longer still.

It’s also rated A on its energy label.

Using the Manhattan Gas Heater in a Power Cut

This is why it belongs in a prepper’s home. The Manhattan gas heater needs no mains electricity at all. The only power it uses is a single AA battery in the ignition button to make the spark, so keep a spare with the heater and take the battery out when it’s put away for summer.

To light the Manhattan gas heater, you turn on the gas at the bottle, press and turn the control knob, and press the spark button to light the pilot. Hold the knob down for at least 10 seconds and the main burner comes on. If the flame ever goes out, wait three minutes before relighting.

Two things worth knowing before the day you need it. First, when you light it for the very first time, burn it outdoors for at least four hours so the synthetic coals can cure, as they give off an odour while they do. Do that in October, not in the middle of a power cut. Second, the pilot stays lit until you turn the gas off at the bottle, so always turn it off at the regulator when you’re done.

Butane, Not Patio Gas: Getting the Bottle

The Manhattan gas heater runs on butane only, from a 7kg or 15kg bottle. It comes fitted with a hose and regulator, but the bottle isn’t included. You’ll get one from a local gas dealer, a garden centre, garage or a builders’ merchant that stocks bottled gas. The first bottle usually comes with a one-off cylinder charge, then you swap the empty for a full one after that.

Don’t be tempted by patio gas or propane bottles. Those are propane, which is for outdoor appliances, and they won’t work with this heater. Ask for butane, and check the regulator fits the valve on the bottle you’re buying.

Keep spare bottles for your Manhattan gas heater outdoors, upright and secure, not in the house. Change bottles in a room with no flames, and if you ever smell gas, turn the bottle off, take it outside and get the heater checked before you use it again.

Who This Manhattan Gas Heater Is For

It suits anyone who wants a proper Calor gas heater as a back-up heat source that looks good enough to leave out all winter. The log-effect fire behind glass looks like a small stove rather than a builder’s heater, so it can live in the living room rather than the shed. It’s a good fit for rural homes that lose power often, households with an older or vulnerable relative who feels the cold, and anyone who’d rather buy from a name they know than gamble on an unbranded import for something that burns gas indoors.

What the Manhattan gas heater isn’t for is heating the whole house, running overnight, or sitting in a bedroom. It’s one room, supervised, with a CO alarm on the wall.

What the Rest of the Team Think

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Pros and Cons

Pros

• The Manhattan gas heater is sold by Calor and Flogas, with a two-year guarantee and a factory helpline
• Oxygen depletion sensor and flame supervision device built in
• No mains power needed, just one AA battery for the ignition spark
• 3.4kW over three heat settings, enough for a living room
• Around 61 hours from a 15kg butane bottle on full power
• Log-effect flames behind glass, smart enough to leave out all winter

Cons

• The Manhattan gas heater costs more than unbranded cabinet heaters
• A full-size bottle sticks out at the back, so it can’t go flat against a wall, but not as far as the cheaper units
• The glass and casing get hot, so it needs a guard or close supervision around children and pets
• Not for bedrooms, bathrooms, basements, high-rise flats or caravans
• Needs a four-hour outdoor burn before its first use indoors

Frequently Asked Questions