Most Common Customer Mistakes
Overloading wood-burning stoves and fireplace inserts
Most wood-burning stoves and fireplace inserts are manufactured and dimensioned for intermittent – discontinuous (temporary) operation, which means they are not intended as a primary heat source for heating buildings, but for use as a so-called secondary source. If a user fires such a stove continuously throughout the entire winter without a break, the stove can overheat, leading to a range of faults from cracked grates, deflectors and firebricks, all the way to warping of the stove body, which is irreparable.
Overloading can also be caused by a lack of familiarity with the operating principles of stoves and inserts – the user needs to understand how the air regulation controls work. In some cases, overheating can also occur due to the air supply being left permanently open; this also leads to high fuel consumption.
Excessive chimney draught can also cause a stove to overheat. When a stove is connected to a chimney with a draught significantly higher than the specified value, this can result in an excessive air supply to the combustion chamber and consequently an intense burn, which in some cases can cause the stove to overheat. The chimney draught must be adjusted to the manufacturer's recommended values.
Prolonged use of wood-burning stoves and fireplace inserts at the lower end of their output range
The opposite problem arises when a stove is purchased with a far greater output than the space actually requires. In that case, the stove overheats the room it is in, which usually leads to the stove being "throttled." Throttling refers to the user intentionally closing the air inlets and the flue damper in order to reduce the stove's output to a "bearable" level. This throttling subsequently causes increased soot and tar build-up inside the stove, flue pipes and the chimney itself. Insufficient air can also impair the correct functioning of the glass wash system and other technologies that require an adequate volume of drawn-in air to operate properly.
This can also occur unintentionally, when the stove is connected to a chimney with insufficient draught. With low chimney draught, the stove is unable to draw in enough air for trouble-free combustion even with the air inlets fully open. This is characterised mainly by smoke escaping from the combustion chamber when loading fuel, a non-functioning glass wash system, and excessive fouling of the flue chamber, flue pipes and the chimney itself.
Reducing the flue pipe diameter below the diameter of the flue gas outlet on the stove or fireplace insert can also cause a reduction in chimney draught, which is why it is always recommended to leave the installation of wood-burning stoves or inserts to professionals. In some cases this reduction is not a problem (for example, when the effective chimney length is sufficient), but this must always be confirmed by a professional.
DIY installation of wood-burning stoves and fireplace inserts
The appliance must always be installed by a professional, whether this involves connecting a hot-water heat exchanger to a hydronic system or connecting the appliance to the chimney via flue pipes. When carrying out DIY installations, people frequently do not know or do not follow basic functional and safety regulations, which can lead to anything from incorrect operation of the stove and loss of warranty to personal injury, for example in the event of a fire. This work must always be left to professionals, and a written record of the installation should of course be obtained, so that the connection can be properly documented.
Using fuel other than the recommended type
This can be illustrated by the example of a user purchasing a wood-burning stove or insert designed for burning wood and wood briquettes, and then burning brown coal or hard coal in it instead. Burning a fuel other than the recommended type can cause, for example, higher temperatures than those for which the stove and its components are designed, which can damage the structure of the appliance itself, spare parts and so on.
The customer should always follow the manufacturer's instructions, which in most cases means that the user should not burn lacquered or otherwise treated wood, exotic wood, etc. This can cause the same damage as using the wrong type of fuel. All information regarding suitable fuels can be found by the customer in the stove's user manual or by enquiring with the manufacturer.