Heating, cooling or ventilating {[HVAC]} devices the heat being derived from the propulsion plant and from a source other than the propulsion plant {from the cooling liquid of the propulsion plant and from a viscous fluid heater}
Heating, cooling or ventilating {[HVAC]} devices the heat being derived from the propulsion plant and from a source other than the propulsion plant {from the cooling liquid of the propulsion plant and from a viscous fluid heater}