Remote controller shows power but cannot change temperature or turn unit on/off

Safety first: None beyond normal electrical safety; this is a low-voltage control issue.

Steps to check:

• Check for lock icon: Many Rinnai remotes have a lock feature. Refer to the user manual to disable the lock (often by holding specific buttons).
• Power cycle: Turn OFF power to the heater for 30 seconds and then restore to reset the controller.
• Inspect cable: Ensure the remote cable is secure and undamaged.

When to call a professional: If the remote remains unresponsive, it or the main control board may need replacement.