Shower trap heat recovery apparatus

Apparatus for recovering waste heat from gray water discharge comprising:

• (a) an elongated first channel accommodating flow of said gray water
• (b) an elongated second channel accommodating flow of a cold water supply, which second channel shares a common conforming extent with said first channel
• (c) a plurality of thermally isolated heat pipes, each in thermal communication with said first and second channels, which heat pipes being serially disposed at intervals along said common extent of said channels
• whereby, said gray water flow direction being counter to said cold water flow direction, said heat pipes provide a means for sequential transfer of incremental quantities of heat from said gray water to said cold water.

Apparatus for exchanging heat between two fluid flowstreams comprising:

• (a) plurality of thermally isolated heat pipes
• (b) a first channel accommodating flow of a first fluid
• (c) a second channel accommodating flow of a second fluid
• wherein each of said heat pipes is in thermal communication with said first and said second channels, which channels are elongated with adjacent conforming common extent.