Rinnai Q85SN Installation & Service Instructions Manual page 91

17.5 Temperature drop of the DHW (Combi)
Temperature drop of the DHW
(Combi)
flow reducing valve
check flow reducing valve for the correct
type in accordance with the installation
instructions
thermostatic mixing
valve incorrectly set
adjust (by measuring the temperature)
DHW power for the
boiler is set too low
-
-
check PARA chapter Step No. 43
check the functioning and wiring of the
DHW sensor T3
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