Water heater is installed but produces hot water only at some fixtures, while others remain cold.

Safety: Turn off power if modifying plumbing. Use caution with hot water.

• Check plumbing layout: Verify that the heater’s hot outlet feeds the entire hot water distribution manifold and not just a subset of fixtures.
• Inspect valves: Ensure all isolation valves on hot branches are open and that any check valves are oriented correctly.
• Bleed air: Run hot water at the affected fixtures for several minutes to clear airlocks.
• Evaluate piping size: Long runs with small-diameter piping may deliver insufficient flow; consult a plumber if necessary.