A drain system and a shower or shower cabin

Abstract

A drain system for recovering thermal energy from a flow of shower or faucet greywater comprises a first drain system inlet for receiving greywater; a drain system outlet for discharging greywater to a drain; and a heat exchanger comprising a grey water inlet arranged downstream of the drain system inlet, and a grey water outlet arranged upstream of the drain system outlet, the heat exchanger being configured to heat a flow of incoming cold water with the greywater flowing from the grey water inlet to the grey water outlet. The drain system further comprises a second drain system inlet for receiving greywater; a by-pass conduit arranged downstream of the second drain system inlet and upstream of the drain, the by-pass conduit being configured to provide a greywater by-pass of the heat exchanger; and an indicator configured to indicate a flow of greywater bypassing the heat exchanger in the by-pass conduit.

Dependencies are inferred from the claim text.