Mixing / Tempering Valve Blend Temperature

Blended delivery temperature, mix ratio, or hot flow for a tempering valve, with a scald-limit flag.

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Formula and source

T_blend = (Qh*Th + Qc*Tc)/(Qh+Qc); inverse hot fraction = (T_target - Tc)/(Th - Tc); hot:cold ratio = (T_target - Tc)/(Th - T_target).

First-principles mixing energy balance for blending hot and cold potable water; the delivery-temperature limits follow the ASSE 1017 (master tempering) and ASSE 1016/1070 (point-of-use scald-guard) device standards and the IPC/UPC scald provisions, by name.

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