Troubleshoot RP27PT/RP17PT

Cold Water Only - Neon Light Off

• FLOW RATE IS TOO LOW - Verify flow rate out of fixture is at or above the minimum .8GPM required for the unit to activate.
• THE WATER SUPPLY IS CONNECTED TO THE OUTLET OF THE UNIT - Verify plumbing connections are correct. See: TWH E2-01. Reconnect the water supply to the inlet of the unit (marked blue).
• ONE OR MORE OF THE HEATING MODULE THERMAL CUT-OUTS HAS TRIPPED - Turn off the power to the heater, remove the cover and locate thermal cutouts on the top of each heating module. Try resetting each cutout by pushing the red reset button located in the center of the cutout. Establish and fix the cause of the overheating. Obstructions in the water path can restrict the flow of water through the heater causing it to overheat. Verify the heater’s inlet filter screen and all outlets served by the heater are clear of debris. Ensure the heater is not being fed preheated water. This water heater is designed for a cold water feed only. If thermal cut outs keep tripping, check for continuity through the elements. See: TWH E2-02.
• PLUMBING CROSSOVER - To test for a plumbing crossover, turn off power supply to the heater. Close installer supplied cold water shut off valve (if none installed, install before proceeding). Open all hot water taps supplied by the heater. Wait 10 minutes and check all faucets. Any water running is a sign of a plumbing crossover. Consult a local plumber or service person for help in correcting a plumbing crossover. To return the heater to service, reinstall cover, open the inlet water supply to the heater and open all hot water taps. Let all taps run until there is no air coming out of the fixtures. Shut off all hot water taps. Turn power supply on to the heater. Return heater to service. (this procedure will prevent the heating elements from dry firing).
• THE FLOW TRANSDUCER IS NOT SPINNING - Turn off the power supply to the heater and remove the cover. Observe if the flow transducer "spins" when the water is turned on. Please note the flow transducer spins at a high speed and can appear to be stopped when actually spinning. It is recommended to observe the flow transducer without water flowing, then turn on a hot water tap while observing the flow transducer. If the flow transducer is not spinning remove, and flush flow transducer. See: TWH E2-21. Contact Technical Support if flushing does not work.
• NO ELECTRICITY AT THE HEATER OR ONE OF THE SUPPLIES HAS FAILED - Have a licensed electrician verify proper wiring and adequate voltage on the terminal block inside the water heater. See: TWH E2-01.

Water Too Cold - Neon Light On

• TEMPERATURE DIAL IS TURNED TOO LOW - Turn the temperature dial located on the bottom of the water heater clockwise for hotter temperatures.
• WATER FLOW TOO HIGH - Adjust water flow to stay within the water heater’s specifications. See: TWH E2-03. Refer to Graph 1 on Page 8 of the manual.
• ONE OR MORE OF THE HEATING MODULE THERMAL CUT-OUTS HAS TRIPPED - Shut off the power to the unit, remove the cover and locate thermal cutouts on the top of each heating module. Try resetting each cutout by pushing the red reset button located in the center of the cutout. Establish and fix the cause of the overheating. Obstructions in the water path can restrict the flow of water through the heater causing it to overheat. Verify the heater’s inlet filter screen and all outlets served by the heater are clear of debris. Ensure the heater is not being fed preheated water. This water heater is designed for a cold water feed only.
• THE POWER SUPPLY VOLTAGE HAS DROPPED - This is likely an issue with the incoming power supply. Measure voltage on the water heater’s terminal block while operating at maximum flow and maximum temperature setting. The RP27PT and RP17PT models are rated for 240V and will also operate at 220V or 208V with reduced output. The output will vary in accordance with the following ratios: volts 208 output ratio 75%, volts 220 output ratio 84% and volts 240 output ratio 100%.
• THE INLET WATER TEMPERATURE IS TOO COLD - Verify the heater is sized appropriately for it’s geographic location. Turn temperature knob located on the bottom of the water all the way clockwise for maximum temperature setting. Ensure flow rates are within the heater’s specifications. Refer to Graph 1 on Page 8 of the manual. Use of an isolation valve on the hot water outlet to control flow rate is recommended.
• ONE OF THE POWER SUPPLIES IS NOT ON - Have a licensed electrician verify adequate voltage on the terminal block inside the water heater, Verify circuit breakers serving the heater are not tripped. Check the supply voltages. PREMATURE ELEMENT FAILURE - Shut off power to the unit and remove cover. Use an ohm meter to verify correct resistance on each element. See: TWH E2-02. If readings are different than listed specifications, contact Technical Support for further instruction.