Quick verdict
Buy it if you want to…
- Warm one room fast
- Turn the central heating down
- Have a safe heater for a parent, children or pets
- Move a heater from room to room
Skip it if you want to…
- Heat a whole house
- Heat a big open-plan room with one heater
- Have a completely silent heater
From £59, about 16p an hour to run, 30-day money back.
How the K1 measures up
| What matters | The K1 | Our honest note |
|---|---|---|
| Warm-up speed | About 2 seconds | Much faster than oil radiators (20–30 minutes) |
| Running cost | About 16p/hour typical, 32p full power | Same efficiency as any electric heater; savings come from heating one room |
| Safety | Tip-over and overheat cut-off, cool-touch casing | No glowing element, no fumes |
| Noise | Gentle fan sound | Not silent; fine for most bedrooms and offices |
| Portability | About 0.5 kg | Easy to carry room to room |
| Room size | Up to about 20 m² | Use two for large or open-plan rooms |
| Warranty and returns | 24 months, 30-day money back | Free tracked UK delivery |
What it's like to use
In the box you get the heater, a remote control and a user manual. There's nothing to assemble: stand it on a flat surface, plug it into the wall and press the power button.
Warm air comes out within a couple of seconds, which is the biggest difference you'll notice if you're used to an oil-filled radiator. Set the temperature with the buttons or the remote, and the thermostat takes over once the room is warm.
The remote is handy if you'd rather not bend down, or want to change the temperature from the sofa or bed.
What it does well
- Very fast warmth. The ceramic core gives warm air in about 2 seconds.
- Targeted heating. It heats the room you're in, so you can turn the central heating down elsewhere.
- Safety features. Tip-over and overheat cut-offs, a self-limiting element and a cool-touch casing.
- Small and light. At about 0.5 kg it moves easily from room to room.
- Simple to use. A few buttons and a remote, with no app or set-up.
Its limits
- It's designed for rooms up to about 20 m². Large open-plan spaces need two units.
- Like all electric heaters, it turns electricity into heat at the same efficiency. Savings come from heating one room instead of the whole house.
- It's a fan heater, so you will hear a gentle airflow.
- It's not rated for bathrooms or wet rooms.
What it costs to run (current UK prices)
At the Ofgem price cap of 26.32p per kWh (1 October to 31 December 2026), a 1200W heater like the K1 costs about 32p an hour at full power. Once the room is warm the thermostat switches the heater on and off, so in normal use it averages about 16p an hour.
| How long | Typical cost per day | Over 30 days |
|---|---|---|
| 1 hour | 16p | £4.74 |
| An evening (4 hours) | 63p | £18.95 |
| A working day (8 hours) | £1.26 | £37.90 |
Your own price may be a little higher or lower depending on your region and tariff. See how we calculate running costs or try the running cost calculator with your own unit rate.
Safety in a home with children, pets or older relatives
If the K1 is knocked over, the tip-over switch cuts the power. If the vents are blocked, overheat protection switches it off. The PTC element limits its own temperature, so there's no glowing coil. These features reduce risk, but no heater replaces sensible use: keep it on a stable surface, a metre from fabrics, and plugged straight into the wall.
Noise, honestly
The K1 uses a small fan to spread heat, so it isn't silent. Most people describe the sound as similar to a quiet laptop. There's no ticking or clicking. If you need total silence to sleep, warm the bedroom before bed and switch it off.
How the K1 compares with other heaters
| Heater type | Warm in | Running cost | Safety and comfort |
|---|---|---|---|
| Ofenwerk K1 (ceramic) | About 2 seconds | About 16p/hour typical | Tip-over and overheat cut-off, cool-touch case, no glowing coil |
| Coil fan heater (2–3kW) | Seconds | 53–79p/hour at full power | Hot coil, can smell of burnt dust, often noisy |
| Oil-filled radiator (1.5–2.5kW) | 20–30 minutes | 39–66p/hour at full power | Surfaces get hot, heavy to move |
| Convector (2kW) | 10–15 minutes | About 53p/hour at full power | Heat rises to the ceiling first |
| Electric blanket (100W) | 10–20 minutes | About 3p/hour | Warms the bed only, not the room |
Full-power costs worked out at 26.32p per kWh. Thermostats lower all of these in real use.
Is Ofenwerk a scam? How to spot a fake heater seller
Lots of "mini heaters" are sold online with exaggerated claims. Here's what to check before buying any heater, and how we measure up:
- Secure checkout from a known provider. We use Shopify's checkout, so we never see your card details.
- A clear returns policy. We give you 30 days, more than the 14 days UK law requires.
- Realistic claims. Watch out for "1p an hour" or "cuts bills by 90%". We publish exactly how we work out costs.
- No fake urgency. We don't use countdown timers or fake stock counters.
- UK plug and UK delivery. The K1 ships with a UK 3-pin plug, with free tracked UK delivery.
- A way to contact the seller. Contact us before you buy if you have any questions. Read more about Ofenwerk.
When the K1 is not the right choice
We'd rather you buy the right heater than return ours. The K1 is probably not for you if:
- You want to heat a large open-plan space over about 20 m² with one heater.
- You want to replace central heating for the whole house.
- You need total silence.
- You need a heater for a bathroom.
Our promise to you
- 30-day money-back guarantee. Try it at home. If you don't love it, return it for a full refund.
- 24-month warranty. If a fault develops, we repair or replace it.
- Free tracked UK delivery. See delivery details.
- Real support. Contact us any time.
Frequently asked questions
Is the Ofenwerk K1 any good?
For warming one room quickly and safely, yes. It warms up in about 2 seconds, has tip-over and overheat cut-offs, and costs about 16p an hour in typical use. It isn't designed to heat a large open-plan space or a whole house.
Is Ofenwerk legit?
Yes. ofenwerk.co.uk is the official UK website. Payment goes through Shopify's secure checkout, and every order has free tracked UK delivery, a 30-day money-back guarantee and a 24-month warranty.
Does the K1 really cost 16p an hour?
At the current UK price cap it costs about 32p an hour at full power. With the thermostat switching on and off in a typical room, the average is about 16p an hour. Colder rooms cost more.
Can I return the K1 if I don't like it?
Yes. You have 30 days to return it for a full refund.
Is the K1 noisy?
It has a gentle fan sound, a bit like a quiet laptop. There's no ticking or clicking.
Is the K1 safe around children and pets?
It has a tip-over switch, overheat protection, a self-limiting ceramic element and a cool-touch casing. As with any heater, keep it on a stable surface and supervise young children.
Will the K1 lower my energy bills?
It can, if it lets you turn down the central heating and heat only the room you're in. We don't promise a fixed saving because it depends on your home and habits.
Sources and how we checked this guide
- Electricity price: Ofgem: energy price cap unit rates and standing charges, checked 25 October 2026.
- Heater safety: UK fire and rescue service advice and Electrical Safety First guidance on portable heaters.
- K1 figures (1200W, about 2-second warm-up, room size up to 20 m², safety cut-offs) come from the product specification.
- Costs are worked out with the method on how we calculate running costs.
More: full specs and price · how it works · running cost calculator.