Troubleshooting the Titan tankless water heater

What’s the main reason that causes Titan tankless water heaters to fail?

Top 5 Titan tankless water heater “not enough hot water” problems.

My Titan water heater doesn't stop heating after I close the hot water.

How to reset or reboot the Titan water heater.

Titan water heater stopped working. All lights (LEDs) are off.

Titan water heater is not working. Green light on, all red lights (LEDs) off.