Ruud electric tanks have two thermostats. Upper integrates the ECO red reset button.
Symptoms
- No hot water (upper stuck open or ECO tripped)
- Boiling water (stuck closed)
- Lukewarm only (lower stuck open)
- Element burned shortly after replacement
Replacement
- Off breaker
- Remove access panel
- Note wire positions; disconnect
- Slide thermostat out
- Insert new; connect wires
- Set to 120°F
- Restore power
Both same temperature
Upper and lower must match. Mismatched = unpredictable performance.
Cost
- Upper with ECO: $30-50
- Lower: $25-40
Bottom line
Test before replacing. Match wires when reconnecting.