Water is warm but not hot enough, even with temperature set high on the controller

Safety first: Avoid setting the temperature above safe levels (typically 120°F/49°C) to prevent scalding.

Steps to check:

• Verify temperature setting: Confirm the controller is set to the desired temperature and not limited by a child lock or external control.
• Reduce flow: Partially close hot water taps to reduce flow and see if temperature increases. If it does, you may be exceeding the heater's capacity.
• Check gas supply: Ensure gas valves are fully open and other gas appliances are not starving the line.
• Schedule maintenance: If the unit is older or in a hard water area, have a technician descale the heat exchanger and clean the burner.

When to call a professional: Persistent low temperature despite correct settings and flow requires gas pressure and combustion checks by a technician.