Wood burning stove problems and solutions — our troubleshooting guide

No matter how much research you do to choose the right wood burning stove, you’ll likely encounter a few problems with your wood burner over the years. From inadequate heat output to smoky emissions, these traditional appliances are subject to a variety of potential problems.

In this short guide, you’ll find answers to six of the most common and troublesome log burner problems. I interviewed experts from HETAS, the national authority on standards in the stove industry, and Logs Direct, a leading wood fuel retailer, to help you diagnose the problem with your wood burner – and find the right solution.

There’s no shame in recognising that some wood burner problems arise due to user error. If you’re uncertain about the best way to start or control the fire in your wood burning stove, refer back to the manufacturer’s instructions, and read our tips on how to maximise the heat from your log burner.

Common log burner problems and how to solve them

1. Glass covered in soot

According to Stephen Talbot, sales director at Logs Direct, sooty glass can result from the fuel used in a stove. “In most cases, if you’re burning properly seasoned, dry wood, the glass on your stove should remain clear,” he says.

“The smallest amount of moisture in the logs can lead to blackening, so if your glass is sooty, it’s likely that the wood you’re burning isn’t fully dry.

“Every situation is different, and stoves can react differently depending on factors like weather conditions and air flow, but nine times out of ten, dry wood is the key to keeping glass glass.”

To prevent your stove’s glass from getting covered in soot, make sure your firewood comes properly seasoned (meaning it has been left to dry over time or dried using a kiln) from a reputable seller. It’s equally important to store the wood in a dry place at your home. The ideal moisture content for firewood is around 15-20%.

Even if you use suitable wood fuel, and even if your stove is equipped with an ‘airwash’ system to reduce soot build-up, it’s likely that your wood burner’s glass window will require occasional attention.

“The size of your stove, how often you burn, and your burning habits will affect the rate of build-up of soot on your stove glass,” says Calvin May, Head of Technical Service at HETAS.

“Your stove’s glass will gradually get dirtier as you use the wood burner, and it will require a quick clean every month or so to keep it looking pristine.”

Avoid using harsh abrasives to clean your log burner’s glass, as they may cause scratches.

Stephen Talbot

Stephen Talbot is a director at Logs Direct, a family-run supplier of kiln-dried firewood logs. Stephen has extensive experience in the wood fuel industry, including 13 years with Logs Direct.

Calvin May

Calvin May is head of technical service at HETAS, an independent, not-for-profit organisation promoting cleaner and safer choices in the use of biomass and other solid fuels, appliances and associated technologies.

2. Smoking wood burner

For Stephen Talbot, this again comes down to the moisture content of your firewood.

“Although smoke production is typical during start-up, ongoing smoke is usually a sign that the wood being burned isn’t adequately dried,” he says. “To reduce smoke emissions, it’s crucial to use properly seasoned wood with less than 20% moisture content.”

According to Calvin May, another common cause of smoking is what is known as a ‘cold plug’. “On particularly cold days, cold air can form a ‘plug’ in your chimney, causing a blockage," he expains. "This prevents air from being drawn up through your flue and expelled from the chimney, leaving it no other path but to go back down, leading to smoke being released from your wood burner.

“Cold plugs during cold spells can be prevented by leaving your stove door open at least thirty minutes before lighting your fire and when your stove isn’t in use, using a top-down method of lighting a fire, and using a firelighter to start your fire. The idea is to gently warm up your flue so that cold plug is eliminated,” he says.

The accumulation of soot or other debris in the chimney is another potential cause of smoking. “It is important to regularly get your chimney swept by a professional, such as a HETAS registered sweep, to prevent these blockages as they are extremely flammable and can lead to chimney fires if left unchecked,” says Calvin.

Smoke emissions inside your wood burner are one thing; but when smoke is escaping from the stove and into your home, you have a far more serious problem that requires immediate action.

3. Wood burner going out after being lit

Every wood burner owner has known the frustration of seeing the fire in their wood burner go out, after being lit.

There are several possible reasons why the fire in a wood burner could go out prematurely. One is improper use of your wood burner vents. These tend to be the trickiest parts of a stove to master, especially for new owners.

“When starting a wood burner, it’s essential to ensure maximum airflow, which means opening all the air vents fully and, on calm days when there’s little outside air movement, leaving the door slightly ajar,” says StepehenTalbot.

“Once the fire is burning steadily, you can gradually adjust the air controls for optimal performance.”

According to Calvin May, some of the other reasons your wood burner might be going out include:

• Cold weather
• Installation issues such as a dirty chimney or flue draught problems
• Firewood is too moist
• Too many large logs used at the outset
• Blockage with soot or other debris

“If you are still having issues getting your fire going after following these tips, it’s best to get a professional involved to assess what is causing the difficulties,” says Calvin May. “Get your chimney swept regularly (at least twice a year when burning wood or annually when burning smokeless fuels), as a blocked chimney can make it much more difficult to get a fire going.”

4. Wood burner not giving out enough heat

Like many wood burner problems, inadequate heat output often stems from using wood fuel that has excessive moisture content.

“If you are operating your wood burner correctly yet your room isn’t warming up, the most likely cause is your fuel,” says Calvin May.

“Burning wet wood means your fire has to work harder to burn the water molecules before it can effectively generate heat. This means it will take longer to heat up and generate much less heat.”

It’s also possible that your wood burning stove has an insufficient heat output for the space you’re attempting to heat. Making the space better insulated, through measures such as installing triple glazing or simply using a draught excluder, could make a positive difference. Many wood burner owners also use the best stove fans to get maximum heat from a wood burner by making better use of heat energy.

5. Wood burner giving out too much heat

Every wood burning stove is made to produce heat output within a definite range, to suit rooms of specific sizes.

“The amount of heat that a log burner produces is measured using the unit ‘kW’ – the higher the number, the more heat emitted from your stove,” says Calvin May. “Speaking to your local HETAS Registered Retailer will help you understand what size stove is right for your room and ensure you purchase a stove that will keep your room at a comfortable temperature.”

If you have inherited your size of wood burner, or if your stove salesperson didn’t discuss this point with you, then there’s a possibility that your stove is too powerful. This can be a tricky problem to solve, as replacing a wood burner is expensive and disruptive. However, Stephen Talbot offers some tips for owners lumbered with an oversized stove:

“If you find that your wood burner is overheating the space, consider simple solutions such as leaving doors open to let the heat circulate or installing vents to disperse heat to other areas, like upstairs rooms,” he says.

If you believe your wood burner has the right specifications for your room, then the excessive heat you’re experiencing may result instead from usage practices. Double check that your firewood is properly seasoned, and try using a little less fuel in one go. Also, keep the stove’s vents less widely opened for a slower burn.

With all that said, Calvin May urges stove owners not to use their overpowered wood burner with small quantities of fuel.

“Running your wood burner at low output as it’s too large for the room is dangerous and can cause an increased build-up of flammable deposits in your chimney,” he says. “It can also lead to incomplete combustion, creating a hazardous amount of carbon monoxide which, due to a cooled chimney working less effectively, can even spill into your room and cause serious health concerns.”

6. Wood burner smells of burning when lit

You’re using your stove to burn stuff, so to a limited extent, you should expect a smell of burning wood when you open the stove door. However, if there’s a strong or unusual burning smell – especially when the stove door is closed – this could point to a problem with your stove.

“Your wood burner should not smell when in use, and regularly smelling an odour when you light your fire could be a sign that you have a problem in your wood burner installation that should be looked at by a professional,” says Calvin May. “Different odours can indicate different things. A burning smell could be due to blockages in your chimney (either a build-up of soot or creosote) or even an issue with your installation.”

Not every unusual smell is linked to a serious wood burner problem. According to Stephen Talbot, new stove owners are likely to encounter a distinctive scent during the first few burns.

“This smell usually disappears after a few uses, but it may briefly return at the start of each season as the stove is fired up again,” he says. “If you notice persistent burning smells, check the stove’s door seal or consult a registered installer to ensure everything is functioning properly.”

A faulty wood burner may produce emissions that go unnoticed by the user, so it’s crucial to have appropriate sensors and alarms set up.

“Keep your carbon monoxide alarm and smoke alarm in working order and test them regularly,” says Calvin May. “These alarms will identify any faults in your installation that you may not be able to pick up.”

Shop carbon monoxide and smoke alarms

Take a look at these freestanding log burner ideas for inspiration on adding a log burner if renovating or building your home. If you are still weighing up which type of heat source to include, our guide on open fire vs log burner is worth a read as well as our guide on bioethanol fireplaces and stoves.