43.222Level 543.22Plumbing, heat and air-conditioning installation43.22201Installation in buildings or other construction projects of: heating systems, electricity, gas and oil-fired boilers, ventilation and air conditioning material and ducting, etc.43.22202Installation of heating, cooling and ventilation systems (except heating)43.22203Installation of electrical heating systems43.22211Construction of fireplaces, furnaces, ornamental fireplaces, etc. powered by electricity