We have recently had a new en suite wet room installed using an Aqualla concealed shower valve and it works absolutely fine with DHW stored at 48C. We heat our water at 3am to utilise off peak cheap electricity and again around 3pm to utilise maximum outside air temperature. I prefer a morning shower and my wife prefers an evening shower and we’ve never run out of hot water or had any weird behaviour with the mixer valve. HTH
1 Like