Oil, gas and solid fuel fired boilers, especially low temperature boilers for oil, gas condensing boilers, wall hung oil and gas boilers, low temperature boilers for gas, cast iron boilers, oil and gas burners for boilers, especially oil and gas pressure jet burners, solar heating devices, especially solar collectors, domestic hot water cylinders, electrical instantaneous water heaters, continuous flow water heaters, heat pumps, heat exchangers, ventilation equipment, namely, ventilators, hea...