Does Central Heating Coal Burn in a Stove? Which Coal Burns in a Stove?

Short answer: yes, but check the size. The real difference between “central heating coal” and “stove coal” is usually grain size. According to the Manisa environment directorate's note, coal should be 18–150 mm, walnut size and up; nut coal of 10–18 mm is only for automatic-feed (stoker) boilers. In a stove with a grate, burn walnut or lump coal.

Current prices and types: Central heating coal prices → · Stove coal

What is the difference between central heating coal and stove coal?

What is sold as “central heating coal” (kalorifer kömürü) is often not a separate type of coal but coal screened to a particular size. The same coal can be screened and bagged as nut, walnut or lump. A stoker boiler's auger needs small, even grains; a stove with a grate needs larger pieces with air gaps between them. The Manisa note draws this line clearly: coal should be 18–150 mm (“no smaller than the size known as walnut”); nut coal of 10–18 mm may only be used in automatic-feed (stoker) boilers.

So the question is not “does central heating coal burn in a stove?” but “how many mm is the coal in this bag?” Walnut-size boiler coal burns in a stove; nut-size boiler coal is not suitable for a stove with a grate.

Which coal size suits which appliance?

If your stove manual asks for a narrower range, that applies. For example, the British maker Charnwood's multi-fuel stove manual asks for coal larger than 50 mm for that model.

Why does nut coal cause problems in a stove with a grate?

In a stove with a grate, combustion air comes from below, up between the grate bars and through the fuel bed; the Charnwood manual describes it this way, and the same manual says not to use small nuts or coal dust. Nut-size grains pack tightly and leave no air path, and those smaller than the grate gaps fall into the ash pan. The result is a starved, smouldering fire. TKİ's stove guide reminds us that worse combustion raises carbon monoxide output.

If you have nut coal, its place is a stoker boiler; we cover the boiler side in which coal to burn in a central heating boiler. If your stove manual does not allow small grains, do not burn them in the stove.

Which coal for a cast iron stove or a bucket stove?

The test is the same for cast iron and bucket stoves: a size that will not fall through the grate and will fit through the door. Walnut (over 18 mm) and lump coal are their fuel; very large pieces (block) are broken up if they do not fit. For bucket stoves, TKİ says to put in a new bucket once the stove is out and light it from the top. For lighting steps see how to light a coal stove; for stoves see our cast iron stove page.

Can coke be burned in a stove?

Coke is not a coal dug from the ground but a processed fuel made by heating coal without air. According to the US Energy Information Administration (EIA), the steel industry uses coal indirectly as coke to smelt iron ore. Some multi-fuel stoves are tested with coke; the Charnwood manual, for instance, lists coke among its test fuels, yet the same manual says petroleum coke is not suitable for that stove. So the decision belongs to your stove's manufacturer manual. The “kök” coal in our range sounds similar but is not coke; according to its bag declaration it is a heating coal of 4,000–4,500 kcal/kg, sold in 40 kg sacks. We explain the difference in anthracite, lignite and coke.

What is the best stove coal?

We do not rank brands; the “best” coal depends on your stove and what you expect. Instead, check these on the bag: calorific value (kcal/kg) and its basis, ash content, sulphur, grain size and certification. The Manisa note says imported coal has a high calorific value and low sulphur; under the Solid Fuels Control Regulation, heating coal is sold bagged and with a Sales Permit. For calorific thresholds see how many calories coal should have, and for reading the bag table see what the values on a coal bag mean. Our fuel calculator gives the quantity for a season.

What does it depend on?

• Appliance type: A stoker boiler needs nut; a stove with a grate needs walnut and lump.
• Grate gaps and door size: Coal must not fall through the grate and must fit the firebox.
• Manufacturer manual: It states suitable fuels and sizes; for special fuels such as coke, it decides.
• Basic coal values: Calorific value, ash, sulphur and moisture.
• Certification: The Sales Permit and the declaration on the bag.

How do you stay safe from stove gas?

The wrong coal size leads to an air-starved fire, and an air-starved fire produces carbon monoxide. Turkey's Ministry of Health describes carbon monoxide as a colourless, odourless, toxic gas; headache, dizziness and weakness are the first symptoms. No fuel is smokeless. If you notice symptoms, open the windows, get out and call 112 (the emergency number in Turkey). Use a carbon monoxide detector wherever a fuel-burning heater is used: stove gas symptoms and carbon monoxide detectors.

Frequently asked questions

Can central heating coal be burned in a stove?

Yes, if it is over 18 mm (walnut and lump). Nut central heating coal of 10–18 mm is for stoker boilers; in a stove with a grate it blocks the air.

Can nut coal be mixed with stove coal?

We do not recommend it. Fine grains fill the gaps between lumps and narrow the air path. Unless your stove manual allows it, use nut coal in a stoker boiler.

Can coke be burned in a stove?

Only if the stove manual allows coke. Some multi-fuel stoves are tested with coke; petroleum coke is not suitable for such stoves. The “kök” coal in our shop is not coke.

What is the best coal for a stove?

There is no single answer. Check calorific value and basis, ash, sulphur, an 18–150 mm size and the Sales Permit; see our article on how many calories coal should have.

Which coal is used in a cast iron stove?

Walnut (over 18 mm) or lump coal that fits the firebox. The size in the manufacturer's manual always comes first.

Sources: Manisa Governorship, Provincial Directorate of Environment and Urbanisation, “Information Note on Air Pollution” (18–150 mm, 10–18 mm nut coal and stoker boilers, calorific value and sulphur of imported coal); Turkish Coal Enterprises (TKİ), “Guide to Using Coal in Stoves” (poor combustion and carbon monoxide, bucket stoves); Charnwood, “Country 16B multi-fuel” operating instructions (primary air through the grate, no small nuts or coal dust, 50 mm, coke and petroleum coke); US Energy Information Administration (EIA), “Use of coal” (coke in steelmaking); Official Gazette of Turkey, “Regulation on the Control of Solid Fuels for Air Quality” (Art. 11: Sales Permit, bagged sale); Turkish Ministry of Health, “Carbon Monoxide Poisoning”.