摘要 |
<p>An apparatus for preventing waterlogging of the sensor and controller valves used to regulate operation of the vacuum interface valve in a sump vented vacuum sewerage system. A float valve operates in accordance with the sewage level in a sump pit and communicates atmospheric pressure to the sensor and controller valves while the sewage level is below a predetermined limit, but closes passage of sewage therethrough once the sewage level exceeds the predetermined limit. A pressure-relief valve may also be operatively connected to the float valve that vents excessive hydrostatic pressure buildups in the sump pit to the atmosphere.</p> |