Property and house boilers


Property and house boilers include solid-fuel boilers, oil and gas heating systems, hot-water boilers and closed expansion vessels with a built-in diaphragm used in heating systems. The choice of heating system is affected by heating needs, fuels available, output and financial and environmental issues.


Installation of solid-fuel boilers must take place in accordance with the manufacturer's instructions and be performed by a qualified installer. Installations of oil and gas heating systems must be performed by a qualified operator approved by Tukes: oil heating system installation companies and gas installation companies. Unqualified and incorrect boiler installation may even endanger the user's life.


The boiler supplier must:

  • provide all the necessary information and instructions regarding boiler usage in writing in Finnish and Swedish (user, maintenance and installation instructions, details regarding supervision and inspections);
  • provide user training if necessary.


The safe use of a heating boiler requires that the boiler:

  • is safe and in conformity with regulations;
  • has been assembled and installed correctly; and
  • has been placed in a fire-safe location.


When acquiring a solid-fuel boiler, particular attention should be paid to overheating protection, backfire prevention and boiler and flue compatibility. Installation, user and maintenance instructions must provide information about:

  • overheating protection;
  • backfire prevention;
  • boiler and flue compatibility and safety distances;
  • boiler nominal output levels; and
  • flue gas temperatures.


Wood-fired boilers must have appropriate overheating protection, such as a cooling coil. Automated fuel feed equipment must always be protected to prevent backfire. Backfire can be prevented using methods such as an extinguishing system, rotary feeder or structural arrangements of the feeding system.


Boiler values must not exceed the corresponding flue values. Most fires in metal flues are caused by boiler and flue incompatibility, with higher-output boilers connected to flues with too low capacity.


The property owner and occupant are responsible for the use, maintenance, chimney sweeping and usage-related inspections of equipment. The flue must be swept and inspected at least once a year. In important groundwater areas underground oil containers must be inspected at regular intervals by a qualified inspection agency approved by Tukes: oil tank inspection agencies. The first inspection must take place within 10 years of commissioning. The date of the next inspection depends on the tank condition classification given on the basis of the first inspection.


There must be at least one portable fire extinguisher and a hose reel or an easily accessible water hose constantly connected to water supply in the immediate vicinity of the boiler room. The functioning of the portable fire extinguisher must be inspected every two years at the minimum. The functioning of portable fire extinguishers is inspected by portable fire extinguisher outlets  approved by Tukes.