Experiments carried out in the fire-chamber of a TGMP - 114 boiler at the GRES-19 district power plant of Lenenergo power system are reported. Their purpose was to verify the low-temperature vortical method of fuel combustion to lower toxic emissions. The composition of flue gases, concentration of mechanical undercombustion, nitrogen oxides and benz(a)pyrene over the height of the fire-chamber was determined.