The answer to 'why is my water line no hot water' is that there are several common causes, including a malfunctioning water heater, a problem with the thermostat or heating element, a leak in the hot water line, or a blockage in the system. Symptoms may include no hot water coming from the taps, lukewarm water, or the water heater not turning on.
To troubleshoot, first check the water heater itself - ensure it has power, the thermostat is set correctly, and there are no visible leaks. If the heater seems to be working, the issue may be with the plumbing lines. Inspect the hot water lines for any leaks or blockages. You may need to call a professional plumber if the problem persists or you're uncomfortable making repairs yourself.