Handyman replaced a 40-gallon gas heater in a closet.

He violated multiple code requirements (IRC P2804.6 / UPC 608.5) creating a scald hazard and potential explosion risk:

1. Undersized Pipe (Critical): 1/2" PEX is prohibited. Discharge piping must match the T&P valve outlet size (typically 3/4") for the full length. 1/2" restricts flow, preventing the valve from relieving pressure fast enough.
2. Improper Material/Connection: PEX generally cannot connect directly to the T&P valve outlet (requires 6" of metal pipe first per most manufacturers/listings). A threaded adapter on the end of PEX into a glued drain fitting is not a listed transition and will likely leak or blow off under pressure.
3. Upward Routing: Piping runs up over a shelf. Code requires piping to slope downward continuously to the termination point by gravity. Trapped water freezes, corrodes the valve seat, or blocks discharge.
4. No Air Gap: "Tied into the drain with a glued fitting" implies a direct connection. Requires an air gap (typically 2x pipe diameter) above the flood rim of the floor drain/funnel. Direct connections risk backflow contamination and siphonage.
5. No Support: PEX sagging over a shelf lacks required support every 32" (horizontal) / 48" (vertical).

Fix: Repipe in 3/4" copper or CPVC (or listed 3/4" PEX if manufacturer allows direct connect, usually not) from valve outlet. Run downward only to terminate 6" above floor drain rim (air gap), supported per code. No valves, tees, or reducers.

The handyman made several critical safety and code violations with the T&P (temperature and pressure) relief valve discharge piping:

1. Incorrect Material: T&P discharge must be made of rigid, heat-resistant material rated for 210°F+ (e.g., copper, CPVC, or galvanized steel). PEX is not permitted — it can soften, deform, or fail under high-temperature discharge, risking scalding or flooding.

1. Improper Routing: The discharge pipe must drain by gravity to a safe location (floor drain, outside, or indirect waste receptor). Running it up over a shelf and then down creates a trap that can hold water, preventing proper drainage and potentially causing pressure buildup or valve malfunction.

1. No Air Gap or Indirect Waste: The discharge must terminate above the drain grate with an air gap (typically at least 1 inch or twice the pipe diameter) to prevent backflow contamination. Gluing a fitting directly into the drain violates this — it creates a direct connection, risking sewer gas entry or siphoning.

1. Threaded Adapter on End: The end of the T&P discharge pipe must be plain (unthreaded) to prevent capping or obstruction. A threaded adapter invites someone to cap it — which is extremely dangerous and can lead to explosion.

1. Pipe Size: While 1/2-inch is minimum allowed, it must be same size as the valve outlet (usually 3/4" for residential heaters). Using 1/2" restricts flow and may not relieve pressure adequately.

Correct Fix: Replace the PEX with rigid copper or CPVC, run it straight down (no upward loops), maintain full size, end with a plain pipe terminating above the drain with an air gap, and do not glue or thread the end.

This is a serious hazard — improper T&P discharge can lead to catastrophic failure. Recommend immediate correction by a licensed plumber. (References: IPC 504.6, IRC P2804.6, UPC 608.5)