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500 Tennessee Waltz Parkway, Ashland City, TN 37015

Technical Support: 800-527-1953 • Parts: 800-433-2545 • Fax: 800-644-9306

www.hotwater.com

Содержание dre-120

Страница 1: ...ER HEATERS MODELS DRE 52 80 120 SERIES 100 DVE 52 80 120 SERIES 100 INSTALLATION CONSIDERATIONS PRE SERVICE CHECKS WATER HEATER CONSTRUCTION OPERATION SERVICE TROUBLESHOOTING 500 Tennessee Waltz Parkway Ashland City TN 37015 http waterheatertimer org How to wire water heater thermostats html http waterheatertimer org 3 phase water heater html ...

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Страница 3: ...former Test 35 24 VAC Transformer Test 36 Immersion Temperature Probes 37 Temperature Sensor Resistance Test 38 Temperature Sensor DC Voltage Test 39 ECO Continuity Test 39 ECO Voltage Test 40 ELECTRONIC CONTROLS 41 CCB Central Control Board 42 CCB Socket Wiring Terminal Identification 43 CCB Enable Disable Circuit s Test 45 Checking Power And Ground To The CCB 46 UIM User Interface Module 47 ELEC...

Страница 4: ...ble for a the installation testing or replacement of gas piping or b the connection installation testing repair or servicing of appliances and equipment that is experienced in such work that is familiar with all precautions required and that has complied with all the requirements of the authority having jurisdiction SERVICE WARNING If you are not qualified as defined by ANSI above and licensed or ...

Страница 5: ...ual is not on hand copies can be obtained from the manufacturers web site or by calling the toll free phone number shown on the back cover of this Service Manual TOOLS REQUIRED Instruction Manual that came with the water heater All tools common to installation and service of commercial water heaters such as hand tools torch pipe wrenches etc Electrical switch lock out device used to secure disconn...

Страница 6: ...m Virtually all commercial and most residential water supply systems are closed systems today Closed water systems will experience thermal expansion which if not controlled with a properly installed and sized thermal expansion tank can cause premature failure leakage of the water heater Water heater failure leakage on closed systems where there is not a thermal expansion tank installed is not cove...

Страница 7: ...circuit conductors and connected to the equipment grounding terminal or lead on the water heater Service Note Electronic Control Models see Figure 2 on page 9 covered in this manual may experience erratic control operation if the water heater is not properly grounded Power Supply Review the electrical requirements listed on the water heater s rating label and in the Instruction Manual that came wi...

Страница 8: ...replacing fuses use an insulated fuse puller to remove and install fuses Always use the correct size for the circuit See the Replacement Fuses Service Note on page 17 in this manual 5 Using an AC volt meter measure the branch circuit power supply voltage to the water heater Ensure the measured voltage of the branch circuit supplying power to the water heater matches the water heater s rating label...

Страница 9: ...indirectly using electromagnetic contactors The control system energizes the electromagnetic contactor s 120 VAC coil causing the switch contacts of the contactor to close which in turn supplies power to the heating elements HEATING ELEMENT CONFIGURATIONS Both types of water heaters covered in this manual are factory equipped with either 3 6 or 9 heating elements depending on how they were ordered...

Страница 10: ...WATER HEATER CONSTRUCTION Servicing should only be performed by a Qualified Service Agent 8 SURFACE MOUNT CONTROL MODELS Figure 1 ...

Страница 11: ...Servicing should only be performed by a Qualified Service Agent 9 WATER HEATER CONSTRUCTION ELECTRONIC CONTROL MODELS Figure 2 ...

Страница 12: ...e used to determine if a heating element is working if there is adequate current flowing through the heating element Ohms The unit of measurement used to quantify the opposition or resistance to the flow of electricity is the ohm As resistance ohms in an electrical circuit increases current amperage will decrease and as resistance decreases current will increase Ohm meters are used for measuring t...

Страница 13: ...ohms law applied to single phase power The KW rating of individual heating elements is marked on the end of each element see page 21 Approximate current amps and resistance ohms for individual heating elements are provided in tables on page 22 See the water heater s rating label for the listed voltage phase power supply requirements total input KW and total full load amp draw of the water heater b...

Страница 14: ...uctions that follow outline how this is done using a standard AC volt meter see Tools Required on page 3 Service Warning Never touch any wiring inside the water heater until the main power supply to the water heater has been secured Secure power to the water heater by turning off the power supply breaker and or disconnect switch AND verify with a volt meter that all wiring has no voltage present b...

Страница 15: ...en L2 and ground in the same way On a 277 volt power supply only one of the two terminals should read 277 volts the neutral will read approximately zero volts On 208 240 volt power supplies each reading should be approximately 120 volts to ground On 480 volt power supplies each reading to ground should be approximately 277 volts Service Warning Zero or low voltage readings between internal wiring ...

Страница 16: ...nd Some 208 volt models will have a stinger leg with one of the three readings to ground measuring 208 volts 208 volt stinger legs should be connected to L2 On 240 volt power supplies each reading should be approximately 120 volts to ground On 480 power supplies each reading to ground should be approximately 277 volts Service Warning Zero or low voltage readings between internal wiring and or Powe...

Страница 17: ...ires 3 Disconnect all red wires from terminal l 3 4 Connect all red wires to terminal L 2 with yellow wires 5 Incoming power will be connected to terminals L 1 and L 2 Service Note 208 volt 54 KW models are three phase only these models CAN NOT be converted to single phase Keep in mind when converting other models from three phase power to single phase power the current amperage will increase sign...

Страница 18: ...ct all blue wires to terminal L 1 with black wires 3 Connect all yellow wires to terminal L 2 with red wires 4 Incoming power will be connected to terminals L 1 and L 2 Service Note 208 volt 54 KW models are three phase only these models CAN NOT be converted to single phase Keep in mind when converting other models from three phase power to single phase power the current amperage will increase sig...

Страница 19: ...e beep the fuse being tested is good and can be re installed 6 If the fuse being tested shows infinite resistance open circuit or the continuity test feature does not sound an audible beep the fuse being tested is blown and must be replaced Volt Meter Method Fuses can also be checked using an AC volt meter The power supply must be turned on and a call for heat must be active all thermostats contac...

Страница 20: ...g the dial on the lower portion of the control The adjustable range is 120 F 49 C to 180 F 82 C The factory default setting is 140 F 60 C ECO The ECO portion of these controls is a manual reset DPDT double pole double throw switch see the Internal Wiring illustration below The ECO is a high temperature limit switch designed to protect against excessively high water temperatures that can be caused ...

Страница 21: ...it wiring is correct see wiring diagram on water heater check fuses page 17 and or restore power to the water heater see pages 12 14 7 With an AC volt meter check for voltage between the L4 and T2 terminals on the control see illustrations below if the measured voltage matches the power supply to the water heater the ECO is resetting properly If the measured voltage between L4 and T2 is low or not...

Страница 22: ...meter and ohm meter are required see Tools Required on page 3 Heating Element Construction The water heater s covered in this manual use electric heating elements to heat water Heating elements convert electrical energy into heat energy Heating elements are constructed with metal tubing Inside the tube is a wire conductor surrounded by an insulating material The wire conductor inside the heating e...

Страница 23: ... The table below represents all available tank sizes 50 80 and 120 gallon models Service Note 208 volt 18 KW models are only available with six 3000 watt elements and 208 volt 36 KW models are only available with nine 4000 watt heating elements Wattage and Voltage Ratings Note some heating elements are dual rated elements IE 208 240 volts 208 VAC 240 277 480 VAC 6 2000 3 3 9 3000 3 3 12 4000 3 3 1...

Страница 24: ...age 8 can draw low amps because power is continuously present at one terminal on each element see the wiring diagram on page 18 Power from the thermostat s L4 terminal is always present at each element and can flow from a grounded element through the water to the storage tank If the measured amps are considerably less than the values in the table above test those elements for grounding see page 25...

Страница 25: ...ng elements by clamping the jaws of the meter around ONLY one of the wires to each heating element See the image below Heating element amp readings should be approximately the same for all heating elements The normal operating amps for all heating elements is provided in the Heating Element Amperage table on page 22 or it can be calculated using ohms law as explained on page 11 Service Note Check ...

Страница 26: ...e range above the expected voltage 600 VAC or higher range initially 7 Check voltage between the two terminals on the heating element see the image below Record the voltage at all heating elements Voltage should match the listed voltage on the water heater s rating label 8 If the measured voltage is zero volts or is not the correct voltage check power to the water heater pages 12 14 check fuses pa...

Страница 27: ... pages 8 and 9 and at the two wiring terminals on the ends of all heating elements 4 Disconnect both power wires from the terminals on the top of all heating elements to be tested 5 Using an ohm meter set the ohm meter to a range just above the expected ohms 200 ohm range initially 6 Touch the ohm meter probes between the two terminals on each heating element see the image below Measure and record...

Страница 28: ...her heating element wiring terminal and ground the heating element is defective and must be replaced Ensure the voltage and KW rating of the replacement heating element is the correct rating for the water heater being serviced see Heating Element Ratings and Heating Element Configurations on page 21 Replacing Heating Elements 1 Secure power to the water heater at the main breaker or disconnect swi...

Страница 29: ...d through the hole in one of the current sensors See the images below Element Sensor Functions Working with the Element Sensors the electronic control system provides valuable operational and diagnostic information to aid in servicing The electronic control system displays animated Status Icons on the UIM to indicate which heating elements are being energized and which heating elements are not bei...

Страница 30: ...from each Element Sensor plugs into one of three sockets on the CCB The J12 J13 and J14 sockets are for heating element Banks 1 2 and 3 respectively See the images below Service Note The Element Sensors cannot be serviced in the field If it is determined one of the three individual current sensors in an Element Sensor is defective the entire Element Sensor assembly must be replaced If current thro...

Страница 31: ...the switch contacts in their normally open state The contactor s switches are closed by an electromagnetic coil inside the base of the contactor When a call for heat is activated the electronic control system sends 120 volts to the contactor s electromagnetic coil As current runs through the coil it becomes magnetized and overcomes the spring tension holding the switch contacts open The switch con...

Страница 32: ...ere are two contactors installed for each Bank IE the illustration shows a 9 element configuration a water heater factory equipped with 6 heating elements would have 4 contactors and a water heater with 3 elements would have 2 contactors Wiring is shown for the first two heating elements in Bank 1 only for simplicity BANK 1 LOWER BANK 2 MIDDLE BANK 3 UPPER 1 2 3 Blk Blk Blu 1 2 3 Red Yel Red 4 5 6...

Страница 33: ...switch contacts IE ants will occasionally infest the switch contacts and eventually cause the contactor to malfunction 5 Physically test the mechanical spring action of the contactor by depressing the contactor mechanism If the action is not smooth and or sticks replace the contactor 6 Perform a close visual inspection of the switch contacts The contacts are silver plated and should be smooth Cont...

Страница 34: ...rably less than 120 volts and or the contactors chatter open and close rapidly ensure the Control Circuit Transformer is wired correctly see page 34 6 If the measured voltage is approximately 120 volts the contactor should close it s switch contacts If the contacts are closed the contactor coil is operating properly 7 If the measured voltage is approximately 120 volts and the contactor s switch co...

Страница 35: ... heater Touch the other volt meter probe to the CCB s J4 OUT 1 wiring terminal See the images below On water heaters equipped with 6 or 9 heating elements also check between the ground connection and the CCB s J4 OUT 2 wiring terminal and on water heaters equipped with 9 elements also check between ground and the CCB s J4 OUT 3 wiring terminal Measure and record voltage readings taken in this Step...

Страница 36: ...g to the primary winding of this transformer must be configured to match the power supplied to the water heater Incorrect wiring can cause output voltage from the transformer s secondary winding to be too low or too high This can cause contactor chatter contacts open and close rapidly and may permanently damage the contactors and or the CCB circuit board The table and illustrations that follow sho...

Страница 37: ...k and the Power Distribution Block ensure wiring is correct and connections are tight and making good contact Check the control circuit fuses see Figure 2 on page 9 for location and the Fuse test procedure on page 17 Verify 120 VAC Control Circuit Transformer wiring is correct see page 34 4 Check Secondary Winding Voltage Using an AC volt meter set the volt meter to an AC voltage range just above ...

Страница 38: ...r of this manual for further assistance if all the procedures above have been performed and 120 VAC is still not present at pins 1 3 of the J1 socket plug on the CCB 4 Check Secondary Winding Voltage Using an AC volt meter set the volt meter to an AC voltage range just above 24 VAC With the J1 plug installed in the J1 socket on the CCB page 42 insert the two volt meter probes into pins 4 5 of the ...

Страница 39: ...rop below 140 F 60 C before the control system can be reset Once the water temperature has cooled below this point the power supply to the water heater must be turned off and on again to reset the control system Temperature Sensor The temperature sensor located inside the Immersion Temperature Probe is a thermistor two black wires Thermistors are thermally sensitive resistors As the water temperat...

Страница 40: ...re the measured resistance value ohms to the values given in the resistance data table below Temperature probes are very reliable and should only be replaced when The resistance test indicates an open infinite resistance or a direct short no resistance circuit The nature of the service problem is temperature control and the resistance readings are considerably 25 or more different than the values ...

Страница 41: ...utside pins red wires of the J5 plug end as shown in the Checking ECO Switch Continuity image below If the ohm meter shows continuity closed circuit between the two outside pins red wires of the J5 plug end the ECO switch has reset properly If the control system continues to lock out displaying the Energy Cut Out ECO Fault message with continuity through the ECO present call the toll free Technica...

Страница 42: ...ably less or more than 120 VAC and all Steps above have been performed call the toll free Technical Support phone number listed on the back cover of this manual for further assistance 5 Check for 120 VAC from the ECO With the J5 plug installed in the J5 socket on the CCB page 42 insert one of the two volt meter probes into pin 1 of J5 plug as shown in the 120 VAC From ECO image below Volt meter pr...

Страница 43: ...ly controls heating elements water temperature and other functions of the water heater Operational information is continuously reported to the user through text and icons on the liquid crystal display LCD portion of the UIM When there are operational problems Fault and Alert messages will also be displayed Users can navigate through multiple control system menus to view operational information and...

Страница 44: ...ly be performed by a Qualified Service Agent 42 CCB CENTRAL CONTROL BOARD All wiring connections and sockets will be identified in the following pages The Troubleshooting section of this manual will refer to this illustration and information ...

Страница 45: ...from transformer 5 24 VAC out from transformer PIN DESCRIPTION 1 120 VAC hot 2 Earth Ground 3 120 VAC neutral TERMINAL DESCRIPTION N O Dry Contact Output Normally Open Terminal Alarm Output Relay N C Dry Contact Output Normally Closed Terminal Alarm Output Relay COM Dry Contact Output Common Terminal Alarm Output Relay TERMINAL DESCRIPTION OUT 1 120 VAC hot to Heating Element Bank 1 Contactor Coil...

Страница 46: ... Not Used J11 Port Communication Port UIM Display user interface module J12 Socket Heating Element Sensors Bank 1 J13 Socket Heating Element Sensors Bank 2 J14 Socket Heating Element Sensors Bank 3 J15 Socket Not Used J16 Socket Not Used J17 Wiring Terminals Not Used PIN DESCRIPTION 1 Enable Disable circuit 1 2 Enable Disable circuit 1 3 Enable Disable circuit 2 4 Enable Disable circuit 2 ...

Страница 47: ...er wires are not installed in the J7 plug call the toll free Technical Support phone number listed on the back cover of this manual for further assistance 3 If there are no external supervisory controls wired to the J7 plug Secure power to the water heater Unplug the J7 plug from the CCB circuit board see page 42 for location 4 Using an ohm meter set the Ohm meter to it s lowest resistance range 2...

Страница 48: ...ero volts or considerably less than 120 VAC Check the 120 VAC wiring between the CCB J2 socket and the 120 VAC Control Circuit Transformer ensure wiring is correct and connections are tight and making good contact Check the J2 plug socket connections on the CCB for wear or damage Ensure they are mating properly and providing good contact see page 42 Check the 120 VAC Control Circuit Transformer to...

Страница 49: ...n the plug end and the UIM Circuit Board back facing out There are six pins on this Ribbon cable socket Ensure all six pins are inserted into the Ribbon Cable plug whenever removing or installing the UIM or Button Pad Overlay Failure to connect this Ribbon cable exactly as shown when servicing will render the User Input Buttons inoperable This should be checked whenever the nature of the service c...

Страница 50: ...l set points for each bank see page 52 Helps reduce operating costs during low moderate loads CONTROL SYSTEM NAVIGATION The UIM User Interface Module is located on the front cabinet of the Electronic Control Model water heaters All operational information and user settings are displayed and accessed using the UIM The UIM includes five snap acting momentary user input buttons an Up Down and 3 Opera...

Страница 51: ...clock page 57 has been initially set Day and Time are adjusted in the Economy Mode Setup menu The current Operating Mode either Normal Mode or Economy Mode is displayed beneath the day and time Menu The left Operational Button is pressed to enter the Main Menu where all control system menus are accessed See Table 3 on page 51 for a list of control system menus Help The right Operational Button is ...

Страница 52: ...elements icon for a water heater equipped with 3 Banks of heating elements Each circle represents one heating element Each diagonal row of 3 elements 1 Bank of elements Open circles represent heating elements the control system has not energized and is not sensing electrical current from Heating elements icon for a water heater equipped with 3 Banks of heating elements Each circle represents one h...

Страница 53: ...and periods Alarm Output Setup The control system s CCB Central Control Board see page 42 features on board SPDT single pole double throw relay contacts for building EMS Energy Management System notification of operational conditions such as Fault Conditions and heating mode status This menu features a list of user definable conditions for relay activation Display Settings Temperature units F or C...

Страница 54: ... is a 1st Differential Setting on all models There will be one additional Differential Setting visible adjustable for each additional Bank of 3 heating elements Operating Sequence With an Operating Set Point of 120 F and all Differential settings at 2 F the On Off sequencing of heating element Banks would be as follows Tank Temperature Non adjustable information display Current water temperature a...

Страница 55: ...Button underneath SELECT to enter the Temperatures Menu If Temperatures is not selected use the Up and Down buttons to select this menu item With the Operating Set Point selected highlight in black in the Temperatures Menu press the Operational Button underneath CHANGE to activate the adjustment mode for this menu item Press the Up and Down buttons to adjust the Operating Set Point to the desired ...

Страница 56: ...le Disable circuits must be closed to enable heating operation If either Enable Disable circuit is open for any reason heating operation will be disabled There is a plug with two jumper wires installed from the factory in the CCB J7 socket to enable heating operation when external controls are not in use Service Note If a supervisory control s is used to enable disable heating operation install fi...

Страница 57: ...he time day has been initially set Note the time will not self adjust for Daylight Savings time Heater In Economy Mode Displays whether the control system is currently operating in Economy Mode or not Daily Operating Mode Sun Mon Tue Wed Thu Fri Sat Seven daily sub menus are listed at the bottom of the Economy Mode Setup menu There are 3 Operating Modes in each sub menu Normal Operation All Day Ec...

Страница 58: ... buttons to select highlight in black Setpoint Adjustment Press the Operational Button underneath CHANGE to activate the adjustment mode for the Setpoint Adjustment value Use the Up Down buttons to change the Setpoint Adjustment to the desired value The Setpoint Adjustment value is adjustable from 2 F to 50 F The factory default is 20 F Notice how the text above the Operational Buttons on the disp...

Страница 59: ...ow the text above the Operational Buttons on the display changes to ACCEPT CANCEL when the adjustment mode is activated and how the current setting is outlined rather than highlighted in black Press the Operational Button underneath ACCEPT to enter and confirm the new setting Pressing the Operational Button underneath CANCEL would discard the new setting and retain the previous setting Use the Up ...

Страница 60: ...yed for Sun Normal Operation Between From the Economy Mode Setup menu Use the Up Down and CHANGE buttons to enter the Mon sub menu as described above Use the Up Down buttons to select highlight in black the Normal Operation Between setting Press the Operational Button underneath SELECT to change the operating mode for Monday to Normal Operation Between Note that when this setting is selected Start...

Страница 61: ... Enable Disable Closed Used for notification and or verification of the enable disable circuits open closed status There are two enable disable circuits available for external supervisory control s at the J7 socket on the CCB see page 42 Enable disable circuit s status can be viewed in the Heater Status Menu see page 54 Temp Heater SP Used for external notification when current tank temperature dr...

Страница 62: ...e user setting that determines how long the UIM s LCD backlight remains illuminated after a key has been pressed Available settings are Always Off 10 30 or 60 seconds and Always On Contrast Adjustable user setting to adjust the UIM s LCD screen contrast between text and background Display Settings Changing the user settings in this menu is done using the same methods outlined in Temperature Settin...

Страница 63: ...n energized Total Heating Time Total accumulated time the control system has been in the heating mode IE any heating elements have been energized Bank Cycles Total accumulated count of heating cycles for each Bank of heating elements Bank On Time Total accumulated heating on time for each Bank of heating elements CCB Version Software version for Central Control Board UIM Version Software version f...

Страница 64: ...elow each listed Fault and Alert message showing when the Fault or Alert condition occurred The Fault History is useful when dealing with intermittent operational problems or when the customer has reset the control system prior to a service agent s arrival With a Fault or Alert item selected press the Operational Button underneath VIEW to display the details for the Fault or Alert message The Faul...

Страница 65: ...derneath YES The display will show text confirming the factory default settings have been restored Press the Operational Button underneath BACK to exit the Restore Factory Defaults menu TEMPERATURES MENU DEFAULT SETTING ADJUSTABLE RANGE Operating Set Point 120 F 49 C 90ºF to 190ºF 32 C to 88 C Differential Settings 2 F 1 C 1 F to 20 F 1 C to 11 C Tank Probe Offset 0 F 0 C 5 F to 5 F 3 C to 3 C ECO...

Страница 66: ... Check all fuses see page 17 8 Check heating elements pages 20 26 9 Check Contactors on Electronic Control Models see pages 29 33 10 Check both enable disable circuits at the CCB s J7 socket on Electronic Control Models If either both circuits are being used by a supervisory control s check that control s settings to ensure it is not disabling heating operation during occupied normal demand period...

Страница 67: ...ation cable problems Important Service Reminder When performing any troubleshooting steps outlined in this service manual always consider the wiring and connectors between components Perform a close visual inspection of all wiring and connectors to a given component before replacement Ensure wires were stripped before being crimped in a wire connector ensure wires are crimped tightly in their conn...

Страница 68: ...oblem has not been corrected after per forming the procedure outlined here Heating Cycle Disabled Control System not activating call for heat with cold tank of water Thermometer Icon on Desktop Screen appears with diagonal line as shown here Possible Causes Fault condition active Enable disable circuit s open Check for and correct any active Fault condition see Current Fault Menu page 62 Check ena...

Страница 69: ...blems Ensure the power supply to the water heater matches the listed voltage on the water heater rating plate Ensure there is not a dead leg of power on 3Ø models see pages 12 14 Check power circuit fuses see page 17 Check heating elements see pages 20 26 Check contactors see pages 29 33 Check power circuit wiring to heating elements from Power Distribution Block to fuse blocks to contactors to he...

Страница 70: ...erature sensor inside the Immersion Temperature Probe see pages 37 39 Replace the Immersion Temper ature Probe if measured resistance is above 56 000 ohms Call the toll free technical support phone num ber on the back cover of this manual for further assistance if the problem has not been cor rected after performing the procedures outlined here Temp Probe Short Fault Condition The control system h...

Страница 71: ...nd socket identification on pages 42 44 Replace damaged plug connectors wiring harness as necessary Check for pinched or broken wiring between the Immersion Temperature Probe and the J5 plug socket connection on the CCB repair or replace damaged wiring as necessary See CCB illustration and socket identification on pages 42 44 Check ECO continuity and for 120 VAC to and from the ECO see pages 37 40...

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Страница 76: ...2 500 Tennessee Waltz Parkway Ashland City TN 37015 Technical Support 800 527 1953 Parts 800 433 2545 Fax 800 644 9306 www hotwater com ...

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