Water-Heater T&P Relief and Discharge

Checks the T&P relief valve's rating against the heater input and reports the IPC 504.6 discharge-pipe size and requirements.

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Formula and source

rating_ok = valve_rating >= heater_input; discharge_in = valve outlet (never reduced). Output is a pass/fail and the IPC 504.6 discharge checklist, not a continuous quantity.

IPC 2021 Section 504 (504.4 valve rating vs heater input, 504.6 discharge piping) and ANSI Z21.22 / CSA 4.4 by name; first-principles comparison.

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