单项选择题
A.suction side of a bilge pump B.exhaust manifold of an auxiliary diesel C.discharge line from an air compressor D.chemical feed tank of an evaporator
A.They should always be started with the discharge valve closed B.They should always be started with the discharge valve opened C.A priming pump is always required to flood the impeller suction D.They should always be started with the sealing line valves closed
A.compressor damage from improper lubrication B.refrigerant absorption by the lubricant C.increased viscosity in the lubricant D.carbon deposit on the compressor suction valves