Abstract: A trap for recovering heat energy from a liquid has a chamber 7 with an internal baffle wall 45-48. An upper chamber opening 9 and a weir at an inlet end 13 of a discharge conduit 11 are on opposite sides of the baffle wall. Liquid fed into the chamber via the upper opening flows downward and under the baffle wall before flowing upward and over the weir to be discharged from the chamber through the discharge conduit. A second liquid flows through a heat exchange conduit 17-24. One preferred embodiment has a concentric arrangement of a plurality of cylindrical baffle walls alternating with a plurality of cylindrical chambers of the heat exchange conduit. A corresponding method of heat recovery is also claimed. In one preferred application, the trap is fitted into the base or floor tray of a shower for recovery of heat energy from waste shower water.

Abstract: A trap for recovering heat energy from a liquid has a chamber 7 with an internal baffle wall 45-48. An upper chamber opening 9 and a weir at an inlet end 13 of a discharge conduit 11 are on opposite sides of the baffle wall. Liquid fed into the chamber via the upper opening flows downward and under the baffle wall before flowing upward and over the weir to be discharged from the chamber through the discharge conduit. A second liquid flows through a heat exchange conduit 17-24. One preferred embodiment has a concentric arrangement of a plurality of cylindrical baffle walls alternating with a plurality of cylindrical chambers of the heat exchange conduit. A corresponding method of heat recovery is also claimed. In one preferred application, the trap is fitted into the base or floor tray of a shower for recovery of heat energy from waste shower water.