Modelling
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      2. Modelling

      Are you able to advise on the pre-heated water temperature?

      Example calculation for pre-heated water temperature.

      This will be predominantly dependent on the WWHRS product, installation system type, and shower flow rate.

      However, based on the Recoup Pipe HEX attached to a shower as System A at 9l/min, then the heat recovery efficiency of the system is (SAP-listed as) 68.1%.

      It’s generally accepted that around 85-90% of the heat energy from the shower head will reach the shower drain, and so a 40-41°C shower will generate shower water with a temperature of c. 34-37°C (ave. 35.5°C ).

      The incoming CWM feed will have a seasonal average of around 12°C.

      At 68.1% efficiency, around 16°C will be transferred to the incoming CWM feed, meaning the remaining shower waste water will have a temperature of 19.5°C [ 35.5-((35.5-12)*68.1)= 19.5 ].

      The preheated CWM feed generated by the WWHRS unit will therefore have a temperature of 28°C