Rheem Marathon Point-of-Use Series Use and Care Manual - Page 11

Operation B. Remove the four (4) screws securing the thermostat access panel and the two (2) thermostat insulation pads, exposing the thermostat. The Limit Switch plastic personnel protector should not be removed. C. With a small screwdriver, adjust the thermostat setting. The 120°F factory set position (the recommended setting) is at the 6 o'clock position (Refer to Figure 10). The temperature settings range from approximately 90°F to approximately 150°F. Reset Button D. Replace the two (2) pieces of fiberglass insulation over the thermostat and attach the thermostat access panel. E. Replace the single piece of fiberglass insulation inside the thermostat access panel cover and snap in position. Thermostat Insulation (2) Access Panel Cover These terminals are not used for 120V models. Temperature Adjustment Screw (Shown at Factory Setting of approx. 120° F.) 150ºF 90ºF 120ºF MID setting equals approximately 120° F water temperature. Figure 10 - Thermostat temperature adjustment. Thermostat Access Panel Cover Cover Insulation Thermostat Access Panel Latch Hole Figure 9 - Removing Thermostat Access panel. NOTE: It is important that the fiberglass insulation is replaced to maintain the water heater's high energy efficiency performance. 3. SAFETY CONTROLS - The water heater is equipped with a combination Thermostat and High Temperature Limit Switch that is located above the heating element. If for any reason the water temperature becomes excessively high, the Limit Switch breaks the power circuit to the heating element. Once the control opens, it must be reset manually. ! CAUTION 4. EMERGENCY INSTRUCTIONS - ! WARNING If water heater has been subjected to flood, fire, or physical damage, turn off power and water to water heater. Do not operate the water heater again until it has been thoroughly checked by qualified service personnel. 5. VACATION AND LONG TIME SHUT-DOWN - If the water heater is to remain idle for an extended period of time, the power and water to the water heater should be turned off to conserve energy. The water heater and piping should be drained if they might be subjected to freezing temperatures. Limit Switch Reset Button These terminals are not used on 120 V models. The cause of the High Temperature Condition must be investigated by qualified service personnel and corrective action taken before placing the water heater in service again. To reset High Limit Switch, turn off power to water heater, remove jacket access panel and insulation, and the access panel and insulation to expose the Thermostat and High Limit Switch. (Refer to Figure 9.) The plastic personnel protector SHOULD NOT be removed. Press the "RESET" button (see Figure 11). Replace insulation and jacket access panel(s) before turning on power to water heater. Temperature Control Thermostat Temperature Adjustment Screw (Shown at Factory Setting of approx. 120° F.) 150ºF 90ºF 120ºF Figure 11 - Thermostat & High Limit Switch 9