Service Manual NR501-OD NR662-OD NRC661 (-DV, -OD) NRC711 (-DV,-OD) Rev: Dec, Contents. NORITZ America Corporation Gas Water Heater

Transcription

1 NITZ America Corporation Gas ater Heater N0-D N-D NC (-DV, -D) NC (-DV,-D) ev: Dec, 0 Service Manual efer to this manual whenever performing service or maintenance on this appliance. This manual will be used for service technician training seminars. The specifications and descriptions in this manual may be changed without prior notice. For further assistance, contact Noritz Technical Support at ---. Do not short circuit any safety device on this appliance Contents Important Safety Information.... Specifications/Performance Table.... Dimensions.... Components.... perating Principle.... peration Flow Chart.... iring Diagram.... Troubleshooting... Error Codes and Checkpoints... board checkpoints... Error Code Diagnostic Flow Charts... ing Maintenance Monitors... Maintenance Monitor List... 0 eplacement... hen Changing the Fan Motor... Gas Line equirements... Manifold Gas Pressure Adjustment... Periodic lnspection... Periodic Maintenance... ater Treatment... Changing Default Temperature Setting... Preventing Freeze Damage.... Installation Check... KS--000

2 Important Safety Information To prevent damage to property and injury to the user, the icons below warn of varying levels of risk. Ignoring this indication will cause an immediate danger of death or arning serious injury. Caution Ignoring this indication may result in death or serious injury. Prohibited.. Safety Tips for Service ear the appropriate clothing and protective gear: Caution In order to prevent injury or accident, wear a protective helmet, safety boots and a lifting belt whenever necessary. Use only the appropriate tools and parts: nly use replacement parts manufactured by Noritz for this model as listed in the arning Installation Manual Parts List for service on this unit. Use appropriate tools. Modification of the unit is prohibited: Do not attempt to modify or alter the unit. This will cause a fire hazard and a risk of electrical shock. hen servicing: arning Disconnect the power supply during maintenance and repairs to reduce the risk of electric shock. If it is necessary to have the electricity connected during repairs, use extreme caution not to touch parts that may cause a shock. Do not short circuit any safety device on this appliance: If a safety device is not functioning properly, replace the part. Do not under any circumstances short circuit the part. Exhaust and gas leakage caution: Always check for leaks when installing or modifying the exhaust vent or gas piping. arning. Post-Service Checks Check parts for leaks: Confirm that there are no gas, water, or exhaust leaks regardless of whether the Caution service performed could have caused them. If the unit is installed indoors, check that the flue collar and vent pipe are installed correctly and that they are in good condition. Confirm that there are no gas, water or exhaust leaks regardless of whether the service performed could have caused them. Check for combustibles: Caution Check insulation resistance: After service or maintenance is completed, check that there are no combustibles in the vicinity of the unit. After service or maintenance is completed, measure the resistance between the arning electrical wires and ground. If it is less than 0MΩ, there is a risk of electrical shock. Properly reconnect the power supply: Confirm that the power supply has been reconnected properly after service or arning maintenance is completed. Also confirm that there is no dust or other obstacles that might cause an electric shock or a fire hazard.

3 . Specifications/Performance Table Item Model Name Type Ignition perating Pressure Minimum Flow ate Dimensions (Height) x (idth) x (Depth) eight ater Holding Capacity Connection Sizes Power Supply Materials N0-D Safety Devices Accessories N-D Item Model Name Type Installation Air Supply/Exhaust ater Inlet Hot ater utlet Gas Inlet Condensate Drain Supply Consumption Ignition perating Pressure Minimum Flow ate Dimensions (Height) x (idth) x (Depth) eight ater Holding Capacity Connection Sizes Power Supply Materials Safety Devices Accessories Specifications Casing Flue Collar Primary Heat Exchanger Secondary Heat Exchanger Installation Air Supply/Exhaust ater Inlet Hot ater utlet Gas Inlet Condensate Drain Supply Consumption Casing Flue Collar Primary Heat Exchanger Secondary Heat Exchanger Specification N0-D utdoor all Mounted Power Vented Direct Ignition -0 psi 0. GPM ( L/min.) 0." (0mm) x." (0mm) x." (0mm) lbs. 0. Gallon (0.L) /" / / N/A 0 VAC (0Hz) NG : LP : Freeze Prevention Zincified Steel Plate/Polyester Coating Stainless Steel Copper Sheeting, Copper Tubing Stainless Steel Sheeting, Stainless Steel Tubing Flame od, Thermal Fuse, Lightning Protection Device (ZN), verheat Prevention Device, Freezing Prevention Device, Fan otation Detector emote Controller, emote Controller Cord, Cross ecessed head screw /" / / N/A 0 VAC (0Hz) NG : LP : Freeze Prevention Zincified Steel Plate/Polyester Coating Stainless Steel Copper Sheeting, Copper Tubing Stainless Steel Sheeting, Stainless Steel Tubing Flame od, Thermal Fuse, Lightning Protection Device (ZN), verheat Prevention Device, Freezing Prevention Device, Fan otation Detector Specification N-D utdoor all Mounted Power Vented Direct Ignition -0 psi 0. GPM ( L/min.) 0." (0mm) x." (0mm) x." (0mm) lbs. 0. Gallon (0.L) emote Controller, emote Controller Cord, Cross ecessed head screw

4 Item Model Name Type Ignition perating Pressure Minimum Flow ate Dimensions (Height) x (idth) x (Depth) eight ater Holding Capacity Connection Sizes Power Supply Materials NC(-DV/-D) Safety Devices Accessories Item Model Name Type Installation Air Supply/Exhaust ater Inlet Hot ater utlet Gas Inlet Condensate Drain Supply Consumption Ignition perating Pressure Minimum Flow ate Dimensions (Height) x (idth) x (Depth) eight ater Holding Capacity Connection Sizes Power Supply Materials NC(-DV/-D) Safety Devices Accessories Casing Flue Collar Primary Heat Exchanger Secondary Heat Exchanger Installation Air Supply/Exhaust ater Inlet Hot ater utlet Gas Inlet Condensate Drain Supply Consumption Casing Flue Collar Primary Heat Exchanger Secondary Heat Exchanger Specification NC-DV NC-D Indoor all Mounted utdoor all Mounted Power Vented Direct Ignition -0 psi 0. GPM ( L/min.)." (00mm) x." (0mm) x." (0mm) 0." (0mm) x." (0mm) x." (0mm) lbs. lbs. 0. Gallon (0.L) /" / / / Threaded 0 VAC (0Hz) NG : LP : NG : LP : Freeze Prevention Freeze Prevention Zincified Steel Plate/Polyester Coating PVC Stainless Steel Copper Sheeting, Copper Tubing Stainless Steel Sheeting, Stainless Steel Tubing Flame od, Thermal Fuse, Lightning Protection Device (ZN), verheat Prevention Device, Freezing Prevention Device, Fan otation Detector emote Controller, emote Controller Cord, Anchoring Screws, SV Conversion Kit, Neutralizer Specification NC-DV NC-D Indoor all Mounted utdoor all Mounted Power Vented Direct Ignition -0 psi 0. GPM ( L/min.)." (00mm) x." (0mm) x." (0mm) 0." (0mm) x." (0mm) x." (0mm) lbs. 0 lbs. 0. Gallon (0.L) /" / / / Threaded 0 VAC (0Hz) NG : LP : NG : LP : Freeze Prevention Freeze Prevention Zincified Steel Plate/Polyester Coating PVC Stainless Steel Copper Sheeting, Copper Tubing Stainless Steel Sheeting, Stainless Steel Tubing Flame od, Thermal Fuse, Lightning Protection Device (ZN), verheat Prevention Device, Freezing Prevention Device, Fan otation Detector emote Controller, emote Controller Cord, Anchoring Screws, SV Conversion Kit, Neutralizer

5 Performance N0-D Item Gas Consumption Maximum Hot ater Capacity Capacity ange Temperature Settings Default Temperature ptions NG LP F ( C) ise F Mode: Maximum Performance 0,000 btuh 0,000 btuh Minimum Performance,000 btuh,000 btuh. GPM (.0 L/min.) GPM (-.0 L/min.) -0 F ( ptions) C Mode: - C (In C intervals), 0,,0 C (In C intervals) ( ptions) 0 F (0 C), 0 F ( C), F ( C), 0 F (0 C) (riginal is 0 F (0 C)) N-D Item Gas Consumption Maximum Hot ater Capacity Capacity ange Temperature Settings Default Temperature ptions NG LP F ( C) ise F Mode: Maximum Performance Minimum Performance 0,000 btuh,000 btuh 0,000 btuh,000 btuh. GPM (.0 L/min.) 0.-. GPM (-.0 L/min.) -0 F (In F intervals) ( ptions) C Mode: - C (In C intervals), 0,,0 C (In C intervals) ( ptions) 0 F (0 C), 0 F ( C), F ( C) 0 F (0 C) (riginal is 0 F (0 C)) NC (-DV/-D) Item Gas Consumption Maximum Hot ater Capacity Capacity ange Temperature Settings Default Temperature ptions NG LP F ( C) ise F Mode: Maximum Performance 0,000 btuh 0,000 btuh Minimum Performance,000 btuh,000 btuh. GPM (. L/min.) 0.-. GPM (-. L/min.) 00-0 F (In F intervals) ( ptions) C Mode: - C (In C intervals), 0,,0 C (In C intervals) ( ptions) 0 F (0 C), F ( C), 0 F (0 C) (riginal is 0 F (0 C)) NC (-DV/-D) Item Gas Consumption Maximum Hot ater Capacity Capacity ange Temperature Settings Default Temperature ptions NG LP F ( C) ise F Mode: Maximum Performance,000 btuh,000 btuh Minimum Performance,000 btuh,000 btuh. GPM (.0 L/min.) 0.-. GPM (-.0 L/min.) -0 F (In F intervals) ( ptions) C Mode: - C (In C intervals), 0,,0 C (In C intervals) ( ptions) 0 F (0 C), F ( C), 0 F (0 C) (riginal is 0 F (0 C))

6 Hot ater Supply Capability <N0-D> 0 [inter] Inlet water temp. 0 [Spring / Fall] Inlet water temp. 0 [Summer] Inlet water temp Set temperature [ ] Set temperature [ ] Set temperature [ ] Flow ate [GPM] 0 0 Flow ate [GPM] 0 0 Flow ate [GPM] <N-D> 0 [inter] Inlet water temp. 0 [Spring / Fall] Inlet water temp. 0 [Summer] Inlet water temp Set temperature [ ] Set temperature [ ] Set temperature [ ] Flow ate [GPM] 0 0 Flow ate [GPM] 0 0 Flow ate [GPM] <NC-DV / NC-D> 0 [inter] Inlet water temp. F 0 [Spring / Fall] Inlet water temp. F 0 [Summer] Inlet water temp. F Set Tempearture [F] Set temperature [F] Set temperature [F] Flow ate [GPM] Flow ate [GPM] Flow ate [GPM] <NC-DV / NC-D> 0 [inter] Inlet water temp. 0 [Spring / Fall] Inlet water temp. 0 [Summer] Inlet water temp Set temperature [ ] Set temperature [ ] Set temperature [ ] Flow ate [GPM] 0 0 Flow ate [GPM] 0 0 Flow ate [GPM]

7 Pressure Loss Characteristics <N0-D> Pressure loss [psi] Pressure loss [Ft. of head] Flow rate [GPM] <N-D> Pressure loss [psi] Pressure loss [Ft. of head] Flow rate [GPM]

8 <NC-DV, NC-D> Pressure loss [psi] Pressure loss [Ft. of head] Flow rate [GPM] <NC-DV, NC-D> Pressure loss [psi] Pressure loss [Ft. of head] Flow rate [GPM]

9 . Dimensions <N0-D> < inch (mm) > - φ0." (φmm) -0." 0." (. mm) NG HLE." (0mm)." (mm).0" (0mm)." (0mm)." (0mm)." (0mm) 0." (0mm) 0." (0mm)." (mm)." (mm)." (mm) 0." 0." (-..mm) NG HLE - φ0." (φmm) 0." (0mm)." (0mm)." (0mm)." (mm) 0." (mm) AI INLET 0." (0mm)." (mm) 0." (0mm) ATE DAIN VALVE (ATE FILTE) HT ATE UTLET ATE DAIN VALVE." (mm)." (0mm)." (mm).0" (mm)." (mm) AI INLET." (mm)." (mm) DISPLAY IND CLD ATE INLET IING THUGHAY IING THUGHAY (AC0V) GAS INLET HEIGHT F EACH FITTING FM BTTM F CASE (N0-D)." (mm)." (mm)." (0mm)." (0mm) HT ATE UTLET (/") HT ATE UTLET CLD ATE INLET GAS INLET CLD ATE INLET (/") (VIE FM TP)." (mm)." (mm)." (0mm)." (mm)." (mm).0" (0mm) GAS INLET (/")." (0mm)." (mm)." (mm) IING THUGHAY IING THUGHAY (AC0V) <N-D>." (mm) < mm (inch) > - φ0." (φmm) -0." 0." (. mm) NG HLE." (0mm)." (mm).0" (0mm)." (0mm)." (0mm)." (0mm) 0." (0mm) 0." (0mm)." (mm)." (mm)." (mm) 0." (0mm) -0." 0." (..mm) NG HLE - φ0." (φmm)." (0mm)." (0mm)." (mm) 0." (mm) AI INLET 0." (0mm)." (mm) 0." (0mm) ATE DAIN VALVE (ATE FILTE) HT ATE UTLET ATE DAIN VALVE." (0mm)." (mm)." (mm)." (mm) AI INLET DISPLAY IND CLD ATE INLET IING THUGHAY IING THUGHAY (AC0V) GAS INLET." (mm)." (mm) HEIGHT F EACH FITTING FM BTTM F CASE (N-D) HT ATE UTLET CLD ATE INLET GAS INLET." (mm)." (mm)." (0mm)." (0mm) HT ATE UTLET (/") CLD ATE INLET (/") (VIE FM TP)." (mm)." (mm)." (0mm)." (mm)." (mm).0" (0mm) GAS INLET (/")." (0mm)." (mm)." (mm) IING THUGHAY IING THUGHAY (AC0V)

10 <NC-DV>." (mm) < inch (mm) > HEIGHT F EACH FITTING FM BTTM F CASE NC-DV -φ0." (φmm) -0." 0." (. mm) NG HLE." (0mm)." (mm).0" (0mm)." (mm) 0." (0mm) 0." (0mm)." (mm) 0." (mm)." (mm)." (0mm)." (0mm)." (mm)." (0mm)." (mm)." (0mm)." (mm) φ." (φmm) φ." (φmm) AI INLET." (00mm) FLUE CLLA CNDENSATE DAIN HT ATE UTLET CLD ATE INLET GAS INLET." (0mm)." (mm)." (mm) (VIE FM TP)." (mm) 0.0" (mm) 0." (0mm)." (mm)." (mm).0" (0mm) CNDENSATE DAIN(/") GAS INLET(/") DISPLAY IND." (0mm)." (0mm)." (0mm) 0." (0mm) -0." 0." (..mm) NG HLE -φ0." (φmm) 0." (0mm) ATE DAIN VALVE HT ATE UTLET ATE DAIN VALVE CNDENSATE DAIN CLD ATE INLET IING THUGHAY (AC0V) GAS INLET ATE DAIN VALVE (ATE FILTE)." (mm)." (mm) 0." (mm) HT ATE UTLET(/") CLD ATE INLET(/")." (0mm)." (mm) IING THUGHAY <NC-D>." (mm) < inch (mm) > HEIGHT F EACH FITTING FM BTTM F CASE NC-D CNDENSATE DAIN 0." (0mm) HT ATE UTLET." (mm) -φ0." (φmm) -0." 0." (. mm) NG HLE." (0mm) 0." (0mm)." (mm).0" (0mm) 0." (0mm)." (mm)." (mm)." (mm)." (0mm)." (0mm)." (mm) 0." (mm) 0." (0mm)." (0mm)." (mm)." (mm)." (mm) AI INLET." (mm)." (mm)." (0mm)." (mm)." (mm) CLD ATE INLET GAS INLET (VIE FM TP)." (mm) 0.0" (mm)." (0mm)." (mm).0" (0mm) CNDENSATE DAIN(/") GAS INLET(/") 0." (0mm)." (0mm) 0." (0mm)." (0mm)." (0mm) -0." 0." (..mm) NG HLE -φ0." (φmm) AI INLET." (mm) ATE DAIN VALVE DISPLAY IND." (mm)." (mm) 0." (mm) HT ATE UTLET(/") CLD ATE INLET CLD ATE INLET(/") IING THUGHAY IING THUGHAY (AC0V)." (0mm)." (mm)." (mm) IING THUGHAY IING THUGHAY (AC0V) HT ATE UTLET GAS INLET ATE DAIN VALVE CNDENSATE DAIN ATE DAIN VALVE (ATE FILTE) 0

11 <NC-DV> -φ0." (φmm) -0." 0." (. mm) NG HLE." (0mm)." (mm).0" (0mm)." (mm) 0." (0mm) 0." (0mm)." (mm) 0." (mm)." (mm)." (0mm)." (0mm)." (mm)." (0mm)." (mm)." (0mm)." (mm) φ." (φmm) φ." (φmm) AI INLET." (00mm)." (mm) < inch (mm) > FLUE CLLA HEIGHT F EACH FITTING FM BTTM F CASE CNDENSATE DAIN HT ATE UTLET CLD ATE INLET." (0mm)." (mm)." (mm) GAS INLET (VIE FM TP)." (mm) 0.0" (mm) NC-DV 0." (0mm)." (mm)." (mm).0" (0mm) CNDENSATE DAIN(/") GAS INLET(/") DISPLAY IND." (0mm)." (0mm)." (0mm) 0." (0mm) -0." 0." (..mm) NG HLE -φ0." (φmm) 0." (0mm) ATE DAIN VALVE HT ATE UTLET ATE DAIN VALVE CNDENSATE DAIN CLD ATE INLET IING THUGHAY (AC0V) HT ATE UTLET(/") GAS INLET ATE DAIN VALVE (ATE FILTE)." (mm)." (mm) 0." (mm) CLD ATE INLET(/")." (0mm)." (mm) IING THUGHAY <NC-D> -φ0." (φmm) -0." 0." (. mm) NG HLE." (0mm) 0." (0mm)." (mm).0" (0mm) 0." (0mm)." (mm) 0." (0mm)." (mm)." (mm)." (0mm) 0." (0mm)." (0mm)." (0mm) -0." 0." (..mm) NG HLE -φ0." (φmm)." (0mm)." (0mm)." (mm) 0." (mm) AI INLET." (mm) 0." (0mm) ATE DAIN VALVE HT ATE UTLET ATE DAIN VALVE CNDENSATE DAIN." (mm)." (0mm)." (mm)." (mm) < inch (mm) >." (mm) AI INLET." (mm)." (mm) DISPLAY IND CLD ATE INLET IING THUGHAY IING THUGHAY (AC0V) HT ATE UTLET(/") GAS INLET CLD ATE INLET(/") ATE DAIN VALVE (ATE FILTE) HEIGHT F EACH FITTING FM BTTM F CASE NC-D CNDENSATE DAIN HT ATE UTLET CLD ATE INLET." (0mm)." (mm)." (mm)." (mm)." (mm) 0." (mm) GAS INLET (VIE FM TP)." (mm) 0.0" (mm)." (0mm) 0." (0mm)." (mm)." (mm).0" (0mm) CNDENSATE DAIN(/") GAS INLET(/")." (0mm)." (mm)." (mm) IING THUGHAY IING THUGHAY

12 . Components <N0-D> Manifold Pressure Tap Thermistor-Cold ater Thermistor-Hot ater <N-D> Manifold Pressure Tap Thermistor-Cold ater Thermistor-Hot ater

13 <NC-DV> Manifold Pressure Tap Thermistor-Cold ater Thermistor-Hot ater <NC-D> Manifold Pressure Tap Thermistor-Cold ater Thermistor-Hot ater

14 <NC-DV> Manifold Pressure Tap Thermistor-Cold ater Thermistor-Hot ater <NC-D> Manifold Pressure Tap Thermistor-Cold ater Thermistor-Hot ater

15 indow The display window allows you to view the status of unit or error codes. ( indow) (Ex.NC-DV) hen the gas burner is on. n hen the gas burner is on, set temperature is displayed for one minute. hen unit is initially plugged into power, set temperature is displayed for approx. three minutes. hen hot water flows. (hen the gas burner is off, and cold water flows.) After one minute elapses from initial call for hot water, the outside edge of the three digit display will rotate in a circular pattern. If there is a problem with the unit, a numerical error code will flash. (Ex.: error code ) hen other indication will appear, please refer to troubleshooting(wner's guide).

16 . perating Principle <NC (-DV, -D), NC (-DV, -D)> Thermistor-Cold ater Gas Proportioning Valve Thermistor- Hot ater

17 <N0-D, N-D> Thermistor-Cold ater Gas Proportioning Valve Thermistor- Hot ater

18 < How to Use >. peration (Hot ater Production). Turn the unit on. - If an optional remote controller is not installed with the unit, the unit will be on as soon as electricity is connected to it. *hen electrical power is connected to the unit, the Set Temperature is displayed for approx. minutes on the indow. - If a remote controller is installed, the "PE" button will need to be pushed to turn the unit on.. henever a hot water fixture is opened, or an appliance that requires hot water is turned on, as soon as the flow sensor detects at least the minimum flow rate required combustion, the fan will iniate and pre-purge any residual combustibles in the combustion chamber. The igniter will then create a spark and the gas valves will open allowing fuel into the combustion chamber where it be ignited by the spark.. hen the flame rod detects a flame, the igniter will stop sparking.. The computer will then control the gas and water control valves to maintain the water at the temperature setting. The temperature can be adjusted by DIP switches on the indow circuit board, or by changing the remote controller setting if one is installed.. hen the demand for hot water ceases, the unit will stop heating. hen the flow sensor detects that the rate has dropped below the minimum rate for continued burning, the gas valves will close and the burner flame will go out. After the post purge removes residual gas from combustion chamber, the unit stops. If necessary, turn off the power by either disconnecting the power supply, or pressing the "PE" button on the remote controller if one is installed.. Error Codes If the flame rod does not detect a flame, or if the high limit switch has been triggered, the gas valves will close, the flame will go out, and an error code will flash on the indow or the ptional emote Controller if one installed. In order to reset the unit and remove the error code, turn the power off by either disconnecting the power supply or by pressing the "PE" on the ptional emote Controller, and then press it again to turn the unit back on. If the problem requires service (the thermal fuse is triggered,etc) the gas valve will stay closed and resetting the unit will not eliminate the error code. If this is the case, the unit must be serviced before it will work again.. Miscellaneous If the unit will not be used for a long period of time, turn off the power, drain the unit of water, and close the manual gas valve on the supply line.

19 . peration Flow Chart <N0-D> ater heating Shutdown procedure Ignition operation

20 <N-D> ater heating Shutdown procedure Ignition operation 0

21 Freeze Prevention Control <N0-D, N-D> Freeze prevention heater Thermistor-Air normal 0,0 / 0 Thermistor-Air less than F ( ) N Heaters turn N Thermistor-Air less than F (- ) N C Heaters turn N Heaters turn N Thermistor-Air more than F (-0 ) N N Thermistor-Air more than F (-0 ) Has 0 min passed N Has 0 min passed N Heaters turn FF Heaters turn FF Thermistor-Air more than F (-0 ) N C Thermistor-Air more than F (-0 ) N C Has min passed N Has min passed N

22 <NC (-DV, -D)> A / B A : ed on indow. B : ed on ptional emote Controller. Connect power ater Servo-Main moves to initial position setting Monitor transmission abnormality High Limit switch abnormality Thermal Fuse abnormality / 0 / 0 / Disconnect power sensor detects < 0. GPM Gas Solenoid Valve abnormality, / Priority Lamp (range) turn FF Initial check normal Gas Proportioning Valve drive circuit abnormality / Gas Proportioning Valve closes Primary Gas Solenoid Valve closes < hen using a ptional emote Controller > Gas Solenoid Valve - closes Gas Solenoid Valve - closes 0 years or more of use Gas Solenoid Valve - closes Priority Lamp (range) lights Self-diagnosis combustion possible < hen using a ptional emote ontroller > Self-diagnosis combustion possible Self-diagnosis combustion possible 0 / 0 0 / 0 The unit is locked 0 / 0 / The unit is locked Fan motor stops Has sec. passed since hot water arning indication ater Servo-Main activates to mid position ater Flow Sensor detected > 0. GPM Initial check normal 0 Condensate Container clogging Thermistor-Cold ater open or shorted Thermistor-Hot ater open or shorted Thermistor-Hot ater abnormality Thermistor-Heat Exchanger open or shorted /, /, / /, / Shutdown * Inlet water high temperature chek normal Thermistor-Exhaust open or shorted Gas Solenoid Valve abnormality abnormality < -DV model only>, /, / 0* / 0 Note ) Ignition operation Fan Motor turn N Fan Motor turn N Gas Solenoid Valve drive circuit abnormality Flame od circuit abnormality ( A or more), / / Fan speed (target / Fan motor stops Fan speed (target / normal 0 / 0 Igniter sparks normal Igniter sparks e-ignition ( times or less) <SV conversion : times or less> 0 / 0 / Primary Gas Solenoid Valve opens Gas Solenoid Valve - opens Gas Proportioning Valve opens Primary Gas Solenoid Valve opens Gas Solenoid Valve - opens Primary Gas Solenoid Valve closes Gas Solenoid Valve - closes 0 Flame od detects A Gas Proportioning Valve opens Gas Proportioning Valve closes 0 Flame od detects A Burner n Indicator lit Igniter stops sparking Gas Solenoid Valve - opens or closes (as necessary) * Gas Solenoid Valve - opens or closes (as necessary) * Gas Solenoid Valve - opens or closes (as necessary) * Igniter stops sparking Igniter stops sparking Ignition operation e-ignition ( times or less) Extinction ( times or less) High Limit Switch normal Primary Gas Solenoid Valve closes Gas Solenoid Valve - closes Gas Proportioning Valve closes <SV conversion : times or less> / / 0 / 0 ater Servo-Main Closes Primary Gas Solenoid Valve closes Gas Solenoid Valve - closes Gas Solenoid Valve - closes Gas Solenoid Valve - closes Gas Proportioning Valve closes * If the inlet water temp. is less than F or if the following statements about K are true, the inlet water temp. will be normal () * Gas Solenoid Gas Solenoid Valve - ver,00 BTU N Valve - Gas Solenoid N N K > ver,00 BTU A pprox.. Total w ater flow o + w ater i nle t t emp. ( F ) Set temp. Less than K Set temp. + ver,000 BTU Valve - N N N N N ver,000 BTU N ver,000 BTU Gas Solenoid Valve - closes At max. BTU is outlet water temp. less than setting Gas Solenoid Valve - closes ater Servo-Main Closes The unit is locked The unit is locked / /, /, / /, / ater Servo-Main activates * / 0 Note ), /, / * / 0* / 0 Note ) Note ) 0 / 0 / Proportional control (gas and fan) verheat prevention device (thermal fuse) triggered ( Condensate Container clogging Thermistor-Hot ater open or shorted Thermistor-Exhaust open or shorted Gas Solenoid - Valve ity Exhaust temperature is too high Safety device triggered Flame od does not (0. A or less) utlet water temp. is too high Thermistor-Cold ater open or shorted Thermistor-Heat Exchanger open or shorted Fan speed abnormality combustion Usage time is equivalent to more than 0 years Note ) A number from to is displayed in * Note ) A number from to is displayed in * Note ) A number or or is displayed in *

23 <NC (-DV, -D)> ater heating Shutdown procedure Ignition operation Note ) =....,,,, Note ) =.. Note ) =., Note ) =.... F # =....,,,,, A, b, C, d, E, F # = 0,....,, # = 0,....,,,,

24 <NC (-DV, -D), NC (-DV, -D)> Freeze prevention control Freeze prevention heater Thermistor-Air less than N N 0, 0 / 0 Thermistor-Air normal Thermistor-Air less than N, / C Heaters turn N Heaters turn N Heaters turn N -DV or SV conversion N N N N Thermistor-Exhaust normal Has 0 min passed N Has 0 min passed N Thermistor-Exhaust less than ( ) N Heaters turn FF Heaters turn FF Heaters turn N Thermistor-Air more than N C Thermistor-Air more than N C Thermistor-Exhaust ( ) or more N Has min passed N Has min passed N Has 0 min passed N Heaters turn FF Thermistor-Exhaust less than F ( ) N Fan motor operation flow ( -DV model ) Fan motor operation flow ( SV conversion ) Thermistor-Exhaust normal N, / Thermistor-Exhaust normal N, / N Thermistor-Exhaust N Thermistor-Exhaust No error code,, / N N No error code,, / Fan motor stopped N Fan Turn N <,00 rpm > N Thermistor-Air normal Thermistor-Air normal N minutes Fan Turn FF N N Fan speed,00 00rpm Thermistor-Air more than N Thermistor-Air more than N Thermistor-Air N / Thermistor-Exhaust F or more N Fan Turn N <,00 rpm > Fan Turn N <,00 rpm > Fan speed set,00 rpm Fan speed set,00 rpm N Thermistor-Exhaust or more Thermistor-Exhaust more than N Fan Turn FF Fan Turn FF Fan speed Target 00rpm N Thermistor-Exhaust N * N Thermistor-Exhaust X or more / Fan Turn FF * hen fan speed is,00rpm, X = F * hen fan speed is,00rpm, X = F

25 . iring Diagram <N0-D, N-D> IING DIAGAM CL CDING : hite : Black : ed GY : Gray B : Brown V : Violet : Blue Y : Yellow G DN Button UP Button Minimum Manifold Pressure Set Button Block Diagram HT NEUTAL 0A(FUSE) GND DC0V DCV FEEZE PEVENTIN HEATE DCV V PE CICUIT PE CNTLLE PIMAY C A SECNDAY B ELAY ELAY VAIST DC0V ELAY VAIST CMBUSTIN FAN ELAY IGNITE IG VAIST AESTE ATE FL SENS ATE SEV - MAIN EATH E GAS PPTINING VALVE PE CNTL CICUIT FLAME DETECTING CICUIT FLAME D EATH GND D CPU CENTAL PCESSING UNIT FAN CNTL UTPUT FAN TATIN SPEED INPUT FAN CUENT VALUE INPUT FAN PULSE CNTL CICUIT Sub-CPU SUB CNTL UNIT A B C D E THEMIST - AI THEMIST - HT ATE THEMIST - CLD ATE THEMIST - HEAT EXCHANGE FLUSH CNNECT HIGH LIMIT THEMAL FUSE SITCH SLENID VALVE 0 SLENID VALVE SLENID VALVE SLENID VALVE GAS SLENID VALVE DIVING CICUIT V PE CICUIT GND

26 <NC (-DV/-D)> DN Button UP Button GND Block Diagram HT NEUTAL DC0V DCV FEEZE PEVENTIN HEATE DCV V PE CICUIT PIMAY PE CNTLLE C SECNDAY A ELAY ELAY HIGH LIMIT SITCH SLENID VALVE 0 B VAIST SLENID VALVE SLENID VALVE SLENID VALVE DC0V ELAY 0A(FUSE) VAIST CMBUSTIN FAN ELAY IGNITE IG VAIST AESTE ATE FL SENS ATE SEV - MAIN EATH E GAS PPTINING VALVE PE CNTL CICUIT FLAME DETECTING CICUIT FLAME D EATH ATE LEVEL ELECTDE DETECTIN CICUIT THEMAL FUSE GAS SLENID VALVE DIVING CICUIT GND D CPU CENTAL PCESSING UNIT FAN CNTL UTPUT FAN TATIN SPEED INPUT V PE CICUIT Minimum Manifold Pressure Set Button FAN CUENT VALUE INPUT GND FAN PULSE CNTL CICUIT Sub-CPU SUB CNTL UNIT THEMIST - AI THEMIST - HT ATE THEMIST - CLD ATE A B C D E THEMIST - HEAT EXCHANGE THEMIST - EXHAUST < -DV MDEL NLY > Y

27 <NC (-DV, -D)> IING DIAGAM CL CDING : hite : Black : ed GY : Gray B : Brown V : Violet : Blue Y G : Yellow DN Button UP Button Minimum Manifold Pressure Set Button Block Diagram HT NEUTAL 0A(FUSE) GND DC0V DCV FEEZE PEVENTIN HEATE DCV V PE CICUIT HIGH LIMIT SITCH PE CNTLLE PIMAY C A SECNDAY B ELAY ELAY VAIST DC0V ELAY VAIST CMBUSTIN FAN ELAY IGNITE IG VAIST AESTE ATE FL SENS ATE SEV - MAIN EATH FLUSH CNNECT THEMAL FUSE SLENID VALVE 0 GAS SLENID VALVE SLENID VALVE DIVING CICUIT SLENID VALVE SLENID VALVE E GAS PPTINING VALVE PE CNTL CICUIT FLAME DETECTING CICUIT FLAME D EATH ATE LEVEL ELECTDE DETECTIN CICUIT GND D CPU CENTAL PCESSING UNIT FAN CNTL UTPUT FAN TATIN SPEED INPUT FAN CUENT VALUE INPUT V PE CICUIT GND FAN PULSE CNTL CICUIT Sub-CPU SUB CNTL UNIT A B C D E THEMIST - AI THEMIST - HT ATE THEMIST - CLD ATE THEMIST - HEAT EXCHANGE THEMIST - EXHAUST < -DV MDEL NLY >

28 . Troubleshooting Error Codes and Checkpoints Error Codes indow 0 0 0,, 0 Note ) Note ) No emote Controller Description Flame od does not detect flame (Flame fault detection) verheat Prevention Device (Thermal Fuse) triggered ly high output temperature High Limit Switch triggered Failure of Gas Solenoid Valve (or Gas Solenoid Valve drive circuit abnormality) Fan Motor abnormality abnormality Gas Solenoid Valve drive circuit abnormality abnormality Flame od circuit abnormality (Detection of flame when no flame is present) setting abnormality (Improper maintenance writers settings) setting abnormality (DIP Switch settings) abnormality abnormality indow transmission abnormality emote Controller transmission abnormality Air flow abnormality (Unit shuts off) Combustion abnormality (arning indication) Combustion abnormality (Unit shuts off) Combustion abnormality (Unit shuts off) Check for accidental extinction of the flame. Check for abnormal combustion. Check Gas Solenoid Valves (,, ). Check Flame od ( 0 ). Check improper connection of earth cable. Check for melting or damage to the Thermal Fuse ( ). Check for improper connection of Thermal Fuse. Measure the resistance through the Thermistor-Hot ater ( ). Check for Gas Proportioning Valve ( ). Check for Manifold Pressure. Check if High Limit Switch is triggered ( ). Check for improper connection of High Limit Switch. failure. failure. Diagnosis Point (Trouble Point) Check the gas supply piping and pressure. Check for Igniter spark ( ). Check Gas Solenoid Valves (,, ). Check Flame od ( 0 ). Check ground, paying special attention to the ground connection to the. Condensate Container clogging Check if the drain line is clogged or frozen ( 0 ). Thermistor - Air abnormality Measure the resistance through the Thermistor Check for an open -Air ( ). Check for improper connection of circuit. Thermistor-Air. Check for a short circuit. Thermistor - Cold ater Measure the resistance through the Thermistor Check for an open abnormality -Cold ater ( ). Check for improper connection of Thermistor-Cold ater. circuit. Check for a short circuit. Thermistor - Hot ater Measure the resistance through the Thermistor Check for an open abnormality -Hot ater ( ). Check for improper circuit. connection of Thermistor-Hot ater. Check for a short circuit. Detection temperature abnormality Thermistor - Heat Exchanger Measure the resistance through the Thermistor Check for an open abnormality -Heat Exchanger( ). Check for improper circuit. connection of Thermistor-Heat Exchanger. Check for a short circuit. Thermistor - Exhaust Measure the resistance through the Thermistor Check for an open abnormality -Exhaust ( ). Check for improper connection circuit. of Thermistor-Exhaust. Check for a short circuit. Check for improper connection of the Gas Solenoid Valves. Check for damage to the Gas Solenoid Valve connections. Failure Check that the fan is rotating and check the pulse frequency from the fan rotational frequency sensor (, ). Check for improper connection of the fan. Check voltage from. Measure the current from the Flame od when there is no flame ( ). Check for a ground fault. Check for improper setting of maintenance writers on. Check the DIP Switch settings. (ex.high elevation, vent length, etc.). failure. failure. Check connection from indow to. Check indow and for damage. Check connection from emote Controller to. Check emote Controller and for damage. Check flue and air inlet for blockage or obstruction. 0 Combustion abnormality Check for abnormal combustion. (Unit shuts off) Check flue and air inlet for blockage or obstruction. 0 Combustion abnormality Check for abnormal combustion. (Unit is locked) Check flue and air inlet for blockage or obstruction. Improper gas type Check gas type C ~ C Note ) CF Note ) C ~ C CF Exhaust temperature is too high Combustion abnormality (Unit is locked) Detect Scale Build-up in the Heat Exchanger (arning indication, and then Unit shuts off) Detect Scale Build-up in the Heat Exchanger (Unit is locked) Note ) =,,,,,,,, Note ) =,,, =,,,,,,,,, A, b, C, d, E, F Note ) =,,,,,,,,, A, b, C, d, E, F failure. Check for abnormal combustion. Check flue and air inlet for blockage or obstruction. Check for abnormal combustion. Check flue and air inlet for blockage or obstruction. Check for abnormal combustion. Check flue and air inlet for blockage or obstruction. Check that flame ignites all across the burner. Check Gas Solenoid Valves (,, ). Check for abnormal combustion ( ). Check for abnormal combustion. Check flue for blockage or obstruction. emarks To reset this error code, the power needs to be disconnected and then reconnected. To reset this error code, the power needs to be disconnected and then reconnected. To reset this error code, the power needs to be disconnected and then reconnected. To reset this error code, the power needs to be disconnected and then reconnected. To reset this error code, the power needs to be disconnected and then reconnected. To reset this error code, the power needs to be disconnected and then reconnected. To reset this error code, the power needs to be disconnected and then reconnected. To reset this error code, the power needs to be disconnected and then reconnected. To reset this error code, the power needs to be disconnected and then reconnected. To reset this error code, the power needs to be disconnected and then reconnected. To reset this error code, the power needs to be disconnected and then reconnected. To reset this error code, the power needs to be disconnected and then reconnected. To reset this error code, the power needs to be disconnected and then reconnected. To reset this error code, contact the nearest NITZ agent. To reset this error code, the power needs to be disconnected and then reconnected. To reset this error code, the power needs to be disconnected and then reconnected. To reset this error code, contact the nearest NITZ agent. Flush the Heat Exchanger to remove the Scale Build-up.efer to the Procedure for Flushing the Heat Exchanger in the Parts List inside pocket of the front cover. If the Heat Exchanger is not flushed, the unit will repeat the warning indication and then shut off.the unit is locked before long.the unit can temporarily operate by reconnecting electrical power until the Heat Exchanger is flushed. Please contact Noritz America for more information about flushing the Heat Exchanger. The unit is locked because of repeated Scale Build-up error code. Must flush the Heat Exchanger to remove the Scale Build-up. Before flushing the Heat Exchanger, please contact Noritz America for more information.

29 <N0-D, N-D> ef. No. 0 - Checkpoints Part verheat Prevention Device (Thermal Fuse) ater Servo-Main Thermistor-Cold ater Thermistor-Hot ater Thermistor - Air Flame od Fan Motor Igniter Primary Gas Solenoid Valve Gas Solenoid Valve - Gas Proportioning Valve Power Supply (Power ) CN & Pin No. CN0 CN CN CN CN CN0 CN - - Burnercase B - - Y - - / CN0 0 - CN0 - CN0 CN0 CN CN0 - - GY / CN0 CN CN CN CN CN0 CN0 CN CN0 DC V 00 Hz - 00 Hz 0 - Ω - Ω 0-0 Ω AC 0 - V DC - V CN - CN DC - V - indow Note ) - Note ) Ω or less Terminal - emote Controller CNA CNB - DC - V -Terminal GND Flame od value Ω or less DC - V DC - V DC - V DC - V Y - DC V or less hen valve is fully open CN - DC V - V 0 - DC V - V ater Flow Sensor CN DC 0. - V CN Y - over 0 pulses/min. Y(+) (-) (over.hz) Thermistor-Heat Exchanger Flame od Gas Solenoid Valve - High Limit Switch CN CN0 - - G - V - - CN & Pin No. CN0 DC -. V CN - CN DC -. V CN - CN DC -. V CN CN CN0 - Electrode - - CN CN0 Gas Solenoid Valve - CN0 - CN0 - Power Supply (Power ) Note ) Cold ater / Hot water / Heat Exchanger Thermistor Temperature Characteristics Temperature ( F) Temperature ( C) esistance (k Ω) Note ) Thermistor - Air Temperature Characteristics Temperature ( F) Temperature ( C) esistance (k Ω) CN board Check points (Check the wiring diagram behind the front cover). - Burnercase - Electrode GND Flame od 0 khz - 00 khz DC 0.μA or less 0 khz - 00 khz DC μa or more DC - V DC 0 - V DC - V DC - V DC - V DC - V - Ω DC - V - Ω DC 0. - V Ω or less 0. - F 0-00 C - F 0-00 C - F 0-00 C hen igniter is sparking hen valve is open Contact resistance Note ) Note ) hen no flame is detected pulse/revolution Coil resistance hen valve is open Coil resistance hen valve is open Coil resistance hen valve is open Coil resistance Coil resistance Note ) Between CN No. of both Main circuit board and window circuit board Note ) Note )

30 <NC (-DV, -D), NC (-DV,-D)> ef. No. Checkpoints - - Burnercase - Electrode B - - Y - - / CN0 - CN0 - CN0 CN0 GY- - 0 ater Level Electrode CN - CN DC. -. V - Part verheat Prevention Device (Thermal Fuse) ater Servo-Main Thermistor-Cold ater Thermistor-Hot ater Thermistor - Air Flame od Fan Motor Igniter Primary Gas Solenoid Valve Gas Solenoid Valve - Gas Proportioning Valve Power Supply (Power ) Power Supply (Power ) CN & Pin No. CN0 CN CN CN CN CN0 CN CN 0 CN CN / CN0 CN CN CN CN CN0 CN0 CN CN0 DC V 00 Hz - 00 Hz 0 - Ω - Ω 0-0 Ω AC 0 - V DC - V CN - CN DC - V - indow Note ) - Note ) Ω or less Terminal - emote Controller CNA CNB - DC - V -Terminal GND Flame od value Ω or less - DC - V - G DC - V CN - V DC - V - DC - V Y - DC V or less hen valve is fully open CN - DC V - V 0 - DC V - V ater Flow Sensor CN DC 0. - V CN Y - over 0 pulses/min. Y(+) (-) (over.hz) Thermistor-Heat Exchanger High Limit Switch CN0 CN0 DC -. V 0 khz - 00 khz DC 0.μA or less DC - V DC 0 - V DC - V DC 0. - V Ω or less - F 0-00 C - F 0-00 C - F 0-00 C hen igniter is sparking hen valve is open Note ) Thermistor-Exhaust CN - CN Note ) Note ) <-DV Model nly> 0 Flame od Gas Solenoid Valve - CN - CN & Pin No. CN - CN DC -. V CN - CN DC -. V CN CN0 - - CN0 Gas Solenoid Valve - CN0 - CN0 - CN0 board Check points (Check the wiring diagram behind the front cover) - Burnercase - Electrode 0 khz - 00 khz DC μa or more DC - V Note ) hen no flame is detected pulse/revolution Coil resistance hen valve is open Coil resistance hen valve is open Coil resistance hen valve is open Coil resistance Coil resistance Note ) Note ) Contact resistance Note ) Note ) Cold ater / Hot water / Heat Exchanger Thermistor Temperature Characteristics Temperature ( F) Temperature ( C) esistance (k Ω) Note ) Thermistor - Exhaust Temperature Characteristics Temperature ( F) - 0 Note ) The N/FF condition of water level electrode can be checked using the maintenance Temperature ( C) monitors. esistance (k Ω)... hen maintenance monitor number reads Voltage (V) "000", the condition of the electrode is normal. hen this monitor reads "00", the condition of Note ) Thermistor - Air Temperature Characteristics the electrode is abnormal. Temperature ( F) - 0 Note ) Between CN No. of both Main circuit board Temperature ( C) and window circuit board esistance (k Ω) GND Flame od DC - V DC - V - Ω DC - V - Ω 0

31 No Error Code Error The Set Temperature is not displayed on indow when electrical power is connected - peration indicator does not light when turned on - The fan does not operate when hot water fixture is opened - utlet water temperature incorrect Page Error Code displayed Error Code indow emote Description Page Controller Ignition failure (Ignitial flame fault detection), Flame od does not detect flame (Flame fault detection) 0 verheat Prevention Device (Thermal Fuse) triggered 0,, ly high output temperature 0 0 High Limit Switch triggered Condensate Container clogging 0, 0 0 Thermistor-Air abnormality, Thermistor-Cold ater abnormality,, Thermistor-Hot ater abnormality, Thermistor-Heat Exchanger abnormality,,, Thermistor-Exhaust abnormality, Failure of Gas Solenoid Valve (or Gas Solenoid Valve drive circuit abnormality),, Fan Motor abnormality 0# Note) 0 abnormality # Note) Gas Solenoid Valve drive circuit abnormality abnormality Flame od circuit abnormality (Detection of flame when no flame is present) setting abnormality (Improper maintenance writers settings) setting abnormality (Dip Switch settings) abnormality No 0 emote control transmission abnormality indow transmission abnormality 0 0 Air flow abnormality (Unit shuts off) 0 Combustion abnormality (arning indication) Combustion abnormality (Unit shuts off) 0 Combustion abnormality (Unit shuts off) 0 0 Combustion abnormality (Unit shuts off) 0 Combustion abnormality (Unit is locked), Improper gas type Exhaust temperature is too high Combustion abnormality (Unit is locked) C # Note) C - C Detect Scale Build-up in the Heat Exchanger (arning indication, and then Unit shuts off) CF# Note) CF Detect Scale Build-up in the Heat Exchanger (Unit is locked) H## Note) H# Detect Scale Build-up in the Heat Exchanger (arning indication after reconnecting electrical power for ten seconds) Note ) # =,,,,,,,, Note ) =,,, # =,,,,,,,,, A, b, C, d, E, F Note ) # =,,,,,,,,, A, b, C, d, E, F Note ) # = 0,,,,,, # = 0,,,,,,,,, It may be difficult to insert the test probes because of the retainer surrounding the connector pins on the. You will need to use a steady hand. Specification of Dummy Flame esistance (M ) Flame od Diodes (Glass tube diode of high frequency or signal) Switch Lead

32 . No Error Code -. The set temperature is not displayed on indow when electrical power is connected. peration indicator does not light when turned on. Check the power outlet voltage. (AC0 - V ) N Check the activation of the indoor distribution board breaker. (Not activated) (Activated) Turn the breaker on. * If activated again, eliminate the cause for activation. Consult power company. ANING Beware of electric shock due to short-circuiting of the 0V circuit. Check the supply voltage of the power circuit board. <CN> CN : Between hite - Black AC0 - V Y 0 <CN> <CN> <CN> 0 GY Main <CN> <CN0> Y 0 VG Y <CN> <CNB> <CN> <CNA> <CN> G <CN0> Y <CN0> / / G <CN0> B Y <CN> Po wer Fuse <CN> indow Data Dip Switch <CN> Check for improper connection of wiring, damage, s h o r t - c i r c u i t i n g, o r g r o u n d f a u l t. eplace the wiring. Check the current fuse (0A). (Not blown) (Blown) * Unplug the power cord when checking. Y 0 <CN> <CN> <CN> 0 GY Main <CN> <CN0> Y 0 VG Y <CN> <CNB> <CN> <CNA> <CN> G <CN0> Y <CN0> / / G <CN0> B Y <CN> Po wer Fuse <CN> indow Data Dip Switch <CN> (nly using the optional emote Controller) Chec k the voltage of the emote Controller terminals on the. (DC - V) CNA, CNB emove the emote Controller cord. eplace the current fuse (0A). * If the fuse blows again, eliminate the cause for the excess current. Check for improper connection of wiring, damage, shor t-circuiting or ground f ault. Chec k the voltage between and on CN0 connecto r. Then replace the set. * It is not necessary to replace the indow. G <CN0> 0 Y <CN> <CN> <CN> 0 GY Main <CN> <CNB> <CN0> Y 0 VG Y <CN> <CNB> <CN> <CNA> <CN> G <CN0> Y <CN0> / / G <CN0> B Y <CN> Po wer Fuse <CN> indow Data Dip Switch <CN> <CNA> Check for emote Controller cord damage, short-circuiting or ground fault, and if there is no problem replace the emote Controller. * If there is cord damage, short-circuiting or ground fault, replace the remote controller cord.

33 -. The fan does not operate when the hot water fixture is opened. Check whether the ater Flow Sensor is normal. Check the indow. hen minute passes after the water flow is detected, the outside edge of the three digit display will rotate in a circular pattern. Check the indow ( ). pen the hot water fixture fully. Co nfirm 0. gal/min. or more by using maintenance monitor #. hen not using the maintenance monitor: CN Betwe en ed 0 Blue DC V or CN Be tween Y ellow (+) Blu e (-) over. Hz 0 Y <CN> 0 Y <CN> <CN> <CN> 0 GY Main <CN> <CN0> <CNB> <CNA> Y 0 VG Y <CN> <CN> G <CN0> <CN> Y <CN0> / / G <CN0> B Y <CN> Power Fuse <CN> indow Data Dip Switch <CN> Check the voltage between ed 0 and Blue. Check the pulses between Yellow and Blue. eplace the * It is not necessary to replace the indow. Check for improper connection of wiring. eplace the ater Flow Sensor. Check whether the Thermistor-Cold ater Detection is too high. (Check the Inlet ater temperature.). eplace the * It is not necessary to replace the indow. * and * to the right do not apply in this case. * << How to check >> The Unit will not run to prevent scalding hot water temperature. [00] : ater inlet temperature is too high If possible decrease water inlet temperature [00] : Predicted water outlet temperature* is too high [00] : Inlet and utlet temperature are reversed Check the pipes and re-install it correctly * If Predicted water outlet temperature is too high, the Unit will not run to prevent scalding hot water temperature. Set Temperature ( F) K ( Predicted water temperature) Less than F F F or more Set Temperature + F K >. Total Flow ate (gal/min) + Thermistor - Cold ater Detection Temperature ( F) A K : Predicted outlet water temperature. : Coe c ient for NC-DV and NC -D Check whether a solar water heater is directly coupled or whether the hot w

34 A Check whether the Thermistor - Cold ater is normal. Check that actual water temperature and maintenance monitor #0 match. hen not using the maintenance monitor: Thermistor-Cold ater converted from the resistance between CN hite - Black (refer to the thermistor temperature characteristics below) and the actually measured water temperature should be about the same. hen measuring the resistance, disconnect the connector and check the male side. 0 Y <CN> 0 Y <CN> <CN> <CN> 0 GY Main <CN> <CN0> <CNB> <CNA> Y 0 VG Y <CN> <CN> G <CN0> <CN> Y <CN0> / / G <CN0> B Y <CN> Power Fuse <CN> indow Data Dip Switch <CN> Ch eck for improper connection of wiring. eplace the Thermistor - Cold ater. eplace the set. * It is not necessary to replace the indow.

35 -. utlet water temperature incorrect nly connect and disconnect the connector after the fan has stopped rotating and then disconnect the electrical power. (The and Fan Motor may be damaged otherwise.) Check whether dots (r ay indow. In this case, the actual outlet water temperature is colder than the Set Temperature. rm Thermistor-Hot ater, ater Ser vo-main, Manifold Pressure, Gas Solenoid Valves / Proportioning Valve are normal. Check whether the Thermistor-Cold ater / Hot ater / Heat Exchanger are normal. Disconnect electrical power, and then open the xture (flow water through the unit). Close the xture, and then reconnect electrical power. Check the maintenance monitor. The d erence between # 0 and # and # data should be within ± F. Check the thermistor resistance. CN hite - Black (Cold ater) CN hite - Black (Hot ater) CN hite - Black (Heat Exchanger) ef er to the thermistor temperature characteristics below. Check for improper connection of wiring, connectors, etc., then replace the thermistor. hen measuring the resistance, disconnect the connector and check the male side. 0 Y <CN> 0 Y <CN> <CN> <CN> 0 GY Main <CN> <CN0> <CNB> <CNA> Y 0 VG Y <CN> <CN> G <CN0> <CN> Y <CN0> / / G <CN0> B Y <CN> Po wer Fuse <CN> indow Data Displ ay Dip Switch <CN> Check that the Thermistor-Hot ater is normal with the outlet water conditions. Tu rn the unit on, and then set the temperature to 00 F and 0 F by using emote Controller*. pen the hot water xture full y, and then con r m Thermistor-Hot ater by the maintenance monitor. # data should be within ± F of the set temperature. * nly when emote Controller is connected. Check the a ter Servo-Main is normal. (Check the maintenance monitor # 0.) Check whether the primary gas pressure is normal. eplace the set. * It is not necessary to replace the Displ ay indow. Maintenance monitor # 0 [000] - [0] : ( 00 is displayed on the emote Controller) Check whether the maintenance monitor # 0 moves between [000] and [0]. [EEE] : Check for improper connection of wiring, then replace the ater Servo-Main. No abnormality in appliance. B * Check the primary pressure (dynamic pressure) at the time of maximum combustion. Primary gas pressure list Gas group Pressure Maximum pressure inch H Standard pressure inch H Minimum pressure inch H Check the gas supply valve, etc. LP NG

36 B Check whether the manifold gas pressure is normal. Check whether the manifold gas pressure can be adjusted. Impossible Check the voltage of the Gas Proportioning Valve. Po ssible CN0:Between ed - Blue hen adjusting the manifold gas pressure, the voltage changes within the range DC 0. - V. echeck after adjusting the manifold gas pressure. * The procedure of Manifold Gas Adjustment is described in page. eplace the set. * It is not necessary to replace the indow. GY 0 <CN0> 0 Y <CN> <CN> <CN> 0 GY Main <CN> <CN0> <CNB> <CNA> Y 0 VG Y <CN> <CN> G <CN0> <CN> Y <CN0> / / G <CN0> B Y <CN> Po wer Fuse <CN> indow Data Displ ay Dip Switch <CN> Check for improper connection of wiring, then replace the Gas Proportioning Valv e. During combustion, press and hold both Maximum and Minimum Manifold Pressure Set Button* and check whether all the burners are burning. * The procedure of Manifold Gas Adjustment is described in page. Check the voltage of Gas Solenoid Valve- (SV), Gas Solenoid Valve- (SV) a n d G a s S o l e n o i d V a l v e - ( S V ). SV CN 0 : Between Black - Blue DC-V SV CN 0 : Between Gray - Blue DC-V SV CN 0 : Between range - Blue DC-V eplace the set. * It is not necessary to replace the Displ ay indow. GY 0 <CN0> 0 Y <CN> <CN> <CN> 0 GY Main <CN> <CN0> <CNB> <CNA> Y 0 VG Y <CN> <CN> G <CN0> <CN> Y <CN0> / / G <CN0> B Y <CN> Po wer Fuse <CN> indow Data Displ ay Dip Switch <CN> Check the Gas Proportioning Valve. Check in the same procedure as. Check for the ater Flow Sensor or w s.

37 . Error Code ed Error Codes indow emote Controller nly connect and disconnect the connector after the fan has stopped rotating and then disconnect the electrical power. (The and Fan Motor may be damaged otherwise.) Description <Condition of occurrence for error code > was not possible at the time of initial ignition due to the causes listed below. (Defective ignition device, leakage of ignition plug, problem in gas supply, poor connection of ground wire, defectiv Chec ck through the peephole of the burner). N Check whether the Igniter is normal. N Check the voltage to the Igniter (on the connector). DC -V between connector Check for improper connection of ignition plug, then replace the Igniter. Check the voltage to the Igniter (on the ). Between : CN Black - CN0 Blue/hite DC - V Check Thermal Fuse and High Limit Switch conduction, and if or less (Thermal Fuse) / or less (High Limit Switch), replace the. <CN> 0 Y <CN> <CN> <CN> 0 GY Main <CN> <CN0> <CNB> <CNA> Y 0 VG Y <CN> <CN> G <CN0> <CN> Y <CN0> / / G <CN0> B Y <CN> Po wer Fuse <CN> indow Data Displ ay Dip Switch <CN> / / G <CN0> Check whether the primary gas pressure is normal. * Check the primary pressure (dynamic pressure) at the time of maximum combustion. Primary gas pressure list Pressure Maximum pressure Standard pressure Minimum pressure Gas group inch H inch H inch H LP NG eplace the Igniter or the Ignition Plug. Check the gas supply valve, etc. Check whether the manifold gas pressure is normal. Check for the Fan Motor clogging, etc. A B