GB705449A - Improvements in or relating to a system for heating and ventilating - Google Patents

Abstract

705,449. Ventilating. BUDD CO. Dec. 31, 1951 [Jan. 3, 1951 ; Oct. 24, 1951], No. 30443/51. Class 137. [Also in Groups XIII and XXXV] In a system for heating and ventilating an enclosure a heating liquid is circulated, the temperature of which is automatically controlled by a thermostat to maintain it at a value dependent on outside temperature, and air heated to a substantially constant temperature is forcibly supplied to the enclosure. Air is supplied to a compartment-type railway car through a duct 61, Fig. 3, supplied by a blower 63 with a mixture of outside air and air returned from the car. The air may be heated by a steam heater 64 or cooled by an evaporator 65, changeover being effected manually. Supply to steam heater 64 is controlled by a solenoidoperated valve 73, responsive to a thermostat 107, which opens to admit steam if the duct temperature falls below a predetermined temperature, e.g. 60‹ F. Thermostats 111 are provided for control when cooling is in operation. Branch ducts, e.g. 80, Fig. 7, supply the individual compartments, each duct being provided with an air spreader 154, a damper 117, and an electric heater 115, the two latter being controlled in the compartment by a knob 121. With damper 117 fully open and electric heater 115 off, position 1 of knob 121, Fig. 15, compartment temperature is a minimum. With the damper admitting only 30 per cent of the maximum volume of air and electric heater 115.fully on, position 11 of knob 121, compartment temperature is a maximum. Intermediate conditions selected by knob 121 are indicated in Fig. 15. A relief valve 81, Fig. 3, prevents undue rise of pressure in duct 61 when many dampers are partially closed. A relay (not shown) prevents energization of the electric air heaters when blower 63 is not operating. To conserve electrical energy when supply voltage is low the electric air heaters are cut out automatically by a low voltage relay (not sliown) and a thermostat 109, Fig. 3, introduced to control valve 73 and maintain a higher duct temperature, e.g. 68‹ F. Toilets have branch ducts 82, Fig. 3, associated with a main exhaust duct 83, Fig. 7, air in which is discharged outside by a blower 84.