摘要 |
Pump apparatus, for delivering oil to an oil burner which is supplied with oil in excess, the excess oil being collected in a vessel, includes a pump receiving oil partly from an oil tank and partly from the collection vessel, for delivering the oil to the burner. The pump is provided with separate inlets for oil from the tank and vessel. In the inlet for oil from the tank there is mounted a shut-off valve adapted for opening under the action of a sub-pressure on the pump suction side. In the inlet for oil from the collection vessel there is mounted a valve adapted for actuation by the head of liquid in the collection vessel for opening or closing when said head is respectively above or below a given level. |