Many issues with water heaters can be repaired. These include leaks, insufficient hot water, strange noises, or pilot issues. Some common repairs involve replacing a thermostat, heating element, or fixing a valve.

Replacing a water heater depends on several factors:

1. Age: Most water heaters last about 8 to 12 years. If yours is approaching this age, consider replacing it.

2. Performance: If you're noticing inconsistent temperatures, longer heating times, or a decrease in hot water supply, it might be time for a replacement.

3. Leaks: Any signs of leaking from the tank or connections indicate it's time to replace the unit.

4. Rusty Water: If your hot water has a rusty color, it could be a sign of corrosion inside the tank.

5. Noises: Popping or rumbling sounds can indicate sediment buildup, which can reduce efficiency and lead to failure.

6. Increased Energy Bills: If your water heater is using more energy than before, it might be less efficient and could need replacing.