Water Heaters

Low pressure on the hot side only (cold is fine)

If cold is fine, the main supply is fine and the restriction is on the hot side: a fixture aerator or cartridge, debris from the tank lodged in a valve or line, a partly closed valve at the heater, or a restrictive heat trap nipple. First find out whether it is one fixture or the whole house; that tells you where to look.

Single source ~45 min easyBrands: All

Before you start

  • Hot water can scald; let lines cool or run water before opening fittings
  • Electric heater: turn the breaker off before draining. Gas heater: set the control to pilot/vacation; do not work on the gas valve or burner

Diagnostic steps

Unlock all 6 steps with expected values

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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Low pressure on the hot side only (cold is fine) · OnCall Tech