Bradford White ElectriFLEX HD™ (Heavy Duty) Commercial Electric Water Heater CEHD SERIES Immersion Thermostat Models SERVICE MANUAL Troubleshooting Guide and Instructions for Service (To be performed ONLY by qualified service providers) Models Covered by This Manual: CEHD(50,80,120)(A) Effective: May, 2019 ECO 8269 Manual 238-51791-00C REV 5/19 Save this manual for future reference
Commercial Electric Energy Saver Water Heater Table of Contents Introduction .................................................................................................................3 Tools Required for Service..........................................................................................3 General Information ....................................................................................................4 Sequence of Operations ........................................................
Introduction This service manual is designed to aid service and maintenance professionals on the function, proper diagnosis and repair of Bradford White Commercial Electric Water Heaters. The text and illustrations in this manual provide step by step instructions to facilitate proper operation and troubleshooting procedures. Contact the Bradford White Technical Support Group immediately if diagnosis cannot be made using the methods described in this service manual.
General Information Bradford White CEHD Series Commercial Electric water heaters are manufactured with an Immersion Thermostat (contactor models). The model number is coded to identify the specific electrical characteristics used for a particular unit. Below is typical model number and coded definitions: In the field this information is determined from the heaters rating plate located on the front of the water heater.
General Controls Layout 5 5
Immersion Style Thermostat Control for Contactor Models The thermostat will complete control circuit voltage upon a call for heat. Likewise, the control will interrupt control circuit voltage when the water temperature is sufficient to satisfy the adjustable temperature limit of control. High Limit Switch Control for Contactor Models The high limit switch will interrupt control circuit voltage causing the heater to shut down when the high temperature limit of the control is reached (196°F±4°F).
Contactor Contactor operation is achieved by energizing an operating coil in response to a call for heat from the immersion thermostat. Upon a call for heat, one or more contactors will energize all heating elements simultaneously. The operating coils are voltage specific, When contactor replacement is required be sure to order the proper operating coil base on the voltage rating found on the rating plate located on the front of the water heater.
Commonly Used Formulas (Single Phase) ࢙ = ࢃࢇ࢚࢚࢙ ࢂ࢚࢙ (Balanced 3 phase) ࢃࢇ࢚࢚࢙ ࢙ = ࢂ࢚࢙ ࢞ .ૠ ࢃࢇ࢚࢚࢙ = ࢙ ࢞ ࢂ࢚࢙ ࡻࢎ࢙ = ࢂ࢚࢙ ࢃࢇ࢚࢚࢙ Common Service Wire Configurations Full Load Current (Amps) kW 6 9 12 13.5 15 18 24 27 30 36 45 54 208 Volt 1 Ph 3 Ph 28.8 16.6 43.2 25.0 57.6 33.3 64.9 37.5 72.1 41.6 86.5 50.0 115.4 66.7 129.8 75.0 144.2 83.3 173.0 100.0 216.3 125.0 259.6 150.0 240 Volt 1 Ph 3 Ph 25.0 14.4 37.2 21.6 50.0 28.9 56.2 32.5 62.5 36.1 75.0 43.4 100.0 57.8 112.5 65.0 125.0 72.
Sequence of Operations CEHD Series Commercial Electric Water Heaters use an immersion thermostat (contactor models). The sequence of operation is explained below. It would be impractical to show all wire diagrams applicable to all configurations. A “typical wiring diagram” is illustrated to aid in understanding the principles of the operating sequence.
Troubleshooting Most common cause for improper electric water heater operation can be linked to heating element failure. When troubleshooting an electric water heater with the incidence of “No Hot Water” or “Insufficient Amount of Hot Water” It is always a good idea to check the heating elements first following the procedure on page 15. Common Heating Element Failures Are: 1. Dry Firing. Elements may be partially submerged in water or most likely, completely exposed with no water in the tank at all.
Troubleshooting WARNING 1. STOP, DANGER! Turn power “OFF” to water heater. 2. Check all wire connections to insure they are snug and corrosion free. High voltage exposure. Use caution when making voltage checks to avoid hazard to life or property. 3. Reset high limit switch (page 15). 4. Check for inoperative heating element (page 12). 5. Check line voltage (page 13), and internal fuses (page 14). 6. Refer to table below if items 1 through 5 above do not correct problem.
Service Procedure I: Heating Element Testing Test for Open or Burned Out Element. WARNING 1. STOP, DANGER! Turn power “OFF” to water heater. High voltage exposure. Use caution when making voltage checks to avoid hazard to life or property. 2. Remove access cover from lower control box. Remove insulation from inside of control box. 3. Disconnect wires from heating element. 4. Set multi-meter to “ohms” setting. 5. Touch probes of multi-meter to screw terminals of heating element (see illustration 1). 6.
Service Procedure II: Line Voltage Testing WARNING Line Voltage Testing Line voltage (single or three phase) will connect to a terminal block located inside the control panel. High voltage exposure. Use caution when making voltage checks to avoid hazard to life or property. Determine heaters voltage and phase by referring to the rating plate located on the front of the heater. Apply the appropriate phase procedure below to determine if proper line voltage is present.
Service Procedure III: Fuse Testing Single Phase Line Voltage Testing WARNING 1. Turn “OFF” power to water heater. 2. Open Control Panel door to allow access to fuse block. 3. Locate fuse block(s) and remove fuses. 4. Set multi-meter to “Ohms” setting. 5. Check continuity across fuse (see illustration 5). A. Continuity IS present, fuse is okay. B. Continuity NOT present, Replace with new fuse. High voltage exposure. Use caution when making voltage checks to avoid hazard to life or property.
Service Procedure IV: Hi Limit Switch Testing Single Phase Line Voltage Testing WARNING 1. This procedure assumes line voltage, transformer, fuses, and thermostat are in working order. 2. Turn power “OFF” to water heater. High voltage exposure. Use caution when making voltage checks to avoid hazard to life or property. 3. Open door or remove lower panel, and remove insulation from inside of the control box. 4. Check for continuity across terminals 1 & 2. (See illustration 6) A.
Service Procedure V: Thermostat Testing Immersion Thermostat Operation Testing WARNING Providing the water temperature in tank is within the operating range of the thermostat, checking thermostat operation can be as simple as rotating the thermostat dial and listening to the contactor(s) to see if they respond to a call for heat. High voltage exposure. Use caution when making voltage checks to avoid hazard to life or property.
Service Procedure V: Thermostat Testing Contactor Operation Testing WARNING Noisy Contactor High voltage exposure. Use caution when making voltage checks to avoid hazard to life or property. Noisy or chattering contactor operation in most cases is due to voltage variations being supplied to the water heater. Extended periods of voltage variations will cause damage to the operating coil of the contactor causing noisy operation.
Service Procedure VI: Contactor Testing Contactor Operating Coils WARNING This procedure assumes control circuit is operating correctly. Providing the water temperature in tank is within the operating range of the thermostat, checking contactor operation can be as simple as rotating the thermostat dial and listening to the contactor(s) to see if they respond to a call for heat. 1.
Service Procedure VII: Thermostat Removal and Replacement Thermostat Control Continuity Testing WARNING 1. STOP, DANGER! Turn power “off” to water heater. 2. Turn off cold water supply to heater. Connect hose to drain spigot of water heater and route to an open drain. Open a nearby hot water faucet to vent heater for draining. Open drain spigot of water heater and allow heater to drain to a point below the immersion bulb location (see illustration 12). High voltage exposure.
Service Procedure VIII: Hi Limit Switch Removal and Replacement Hi Limit Switch Removal WARNING 1. STOP, DANGER! Turn power “off” to water heater. 2. Open control box door or remove lower cover. Remove insulation. Remove plastic cover from hi limit switch. 3. Disconnect wires from Hi Limit switch terminals. NOTE: It may be necessary to label wires for proper re-connection to new Hi Limit switch. High voltage exposure. Use caution when making voltage checks to avoid hazard to life or property. 4.
Service Procedure IX: Heating Element Removal and Replacement Heating Element Removal WARNING 1. STOP, DANGER! Turn power “off” to water heater. 2. Turn off cold water supply to heater. Connect hose to drain spigot of water heater and route to an open drain. Open a nearby hot water faucet to vent heater for draining. Open drain spigot of water heater and allow heater to drain to a point below the elements. High voltage exposure. Use caution when making voltage checks to avoid hazard to life or property.
Service Procedure X: Anode Inspection and Replacement Anode Inspection and Replacement WARNING 1. STOP, DANGER! Turn power “off” to water heater. 2. Turn off cold water supply to heater. Connect hose to drain spigot of water heater and route to an open drain. Open a nearby hot water faucet to vent heater for draining. Open drain spigot of water heater and allow heater to drain to a point below the elements. High voltage exposure.
Parts List Customer must specify complete model number and serial number when ordering service parts.
Parts List 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 Large Control Box Small Control Box Temperature Switch Thermostat Dial Element Insulation Heating Element Element Gasket Inlet Diptube Element Plug ¾” NPT Plug Hi Limit Switch Large Control Panel Small Control Panel Outlet Nipple Anode Hole Plug Anode 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 ¾” NPT Nipple Temperature and Pressure Relief Valve Cleanout Ring Cleanout Cover Cleanout Screw Jacket Cleanout Cover Drain Valve Contactor Terminal Block 600V
