Bradford White ElectriFLEX HD CEHD 50 User manual

Save this manual for future reference
Manual 238-51791-00A REV 08/18
Effective: August 2018 ECO 7960
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)
Bradford White ElectriFLEX HD™(Heavy Duty)
Commercial Electric Water Heater
CEHD SERIES
Immersion Thermostat Models

2
2
Commercial Electric Energy Saver Water Heater
Table of Contents
Introduction...................................................................................................................3
Tools Required for Service...........................................................................................3
General Information......................................................................................................4
Sequence of Operations...............................................................................................9
Troubleshooting.......................................................................................................... 10
Service Procedure I: Heating Element Testing .........................................................12
Service Procedure II: Line Voltage Testing ...............................................................13
Service Procedure III: Fuse Testing ..........................................................................14
Service Procedure IV: Hi Limit Switch Testing ..........................................................15
Service Procedure V: Thermostat Testing ................................................................16
Service Procedure VI: Contactor Testing ..................................................................18
Service Procedure VII: Thermostat Removal and Replacement...............................19
Service Procedure VIII: Hi Limit Switch Removal and Replacement.........................20
Service Procedure IX: Heating Element Removal and Replacement........................21
Service Procedure X: Anode Inspection and Replacement ......................................22
Parts List ....................................................................................................................23
Notes..........................................................................................................................25
Notes..........................................................................................................................26
Notes..........................................................................................................................27





3
SAVE THIS MANUAL FOR FUTURE REFERENCE REV 1/16 238-51791-00A
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.
Tools Required for Service
Multi-Meter: A digital type is strongly recommended. This device is used to measure electrical
values. The meter you select must have the capability to measure volts AC, volts DC, Amps, micro-
amps and ohms.
Thermometer: Used to measure water temperature. An accurate thermometer is recommended.
Drain Hose: Used to for emptying the tank.
Various Hand Tools: Pipe wrench, channel locks, Allen wrench set, screw drivers (common & philips),
¼" nut driver, pliers (common & needle nose), 1-1/16” and 1-1/2” deep well sockets, wire cutters, wire
strippers, wire crimpers, and flashlight.

4
4
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.
ElectricalCharacteristics
ModelNumber
Typical Rating Plate
Located on Front of Water Heater

5
5
General Controls Layout


6
6
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). Once the cause for overheated water
has been determined, the control must be manually reset to restore normal operation.


7
7
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.
Direct Immersion “Screw-in” Type Heating Element

8
8
Commonly Used Formulas
(Single Phase) (Balanced 3 phase)
࡭࢓࢖࢙ ൌ ࢃࢇ࢚࢚࢙
ࢂ࢕࢒࢚࢙ ࡭࢓࢖࢙ ൌ ࢃࢇ࢚࢚࢙ ࢂ࢕࢒࢚࢙࢞૚Ǥૠ૜૛ ࢃࢇ࢚࢚࢙ ൌ ࡭࢓࢖࢙࢞ࢂ࢕࢒࢚࢙ ࡻࢎ࢓࢙ ൌ ࢂ࢕࢒࢚࢙૛
ࢃࢇ࢚࢚࢙
Common Service Wire Configurations
Full Load Current (Amps)
208Volt240Volt277Volt380Volt415Volt480Volt600Volt
kW1Ph3Ph1Ph3Ph1Ph3Ph3Ph1Ph3Ph3Ph
628.816.625.014.421.69.18.312.57.25.8
943.225.037.221.632.413.612.518.710.88.7
1257.633.350.028.943.318.216.725.014.411.5
13.564.937.556.232.548.720.518.828.116.213.0
1572.141.662.536.154.122.720.931.218.014.4
1886.550.075.043.464.027.325.037.521.617.3
24115.466.7100.057.886.636.433.450.028.923.1
27129.875.0112.565.097.441.037.556.232.526.0
30144.283.3125.072.2108.345.641.762.536.128.9
36173.0100.0150.086.7129.954.750.175.043.334.6
45216.3125.0187.5108.3162.468.462.693.754.143.3
54259.6150.0225.0130.0194.982.075.1112.565.052.0



9
9
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.
Immersion Thermostat (Contactor Models): Configured to use a single immersion thermostat to
control one or more contactors to energize or de-energize all elements simultaneously. In addition, a
separate high limit switch with manual reset is wired in series with the thermostat. The thermostat
uses a direct immersion bulb inserted into the tank to sense water temperature, while the high limit
switch is surface mounted to sense the temperature of the tank. The immersion thermostat is
mounted to provide temperature adjustment from the exterior of the unit.
Sequence of Operation:
Immersion Thermostat (Contactor Models).
The system has two distinct circuits.
1. Power circuit (shown solid line).
2. Control Circuit (shown dotted line).
1) Line voltage is applied across terminals of fuse
block or a terminal block. Line voltage continues
down and connects to terminals L1, L2 & L3 of
one or more contactors.
A) Contactor is open (no call for heat), so
there is no voltage across terminal T1,
T2 & T3 of contactor.
B) The contactor is controlled by the
control circuit consisting of the
immersion thermostat, Hi Limit Switch
and contactor coil.
2) When the thermostat calls for heat, contacts
close inside the thermostat completing the circuit
through the Hi Limit Switch and energizing the
contactor coil.
3) The energized contactor coil causes the
contactor to close energizing the elements from
terminals T1, T2 & T3 of the contactor.
4) When the temperature setting of the thermostat
is reached, the contacts in the thermostat open.
This interrupts current flow through the control
circuit de-energizing the contactor coil.
5) The de-energized contactor coil causes the
contactor to open, interrupting current flow
through the elements. The heater is now in
stand-by waiting for the next call for heat.

10
10
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. In open air, an energized element (Dry Fired) will become completely inoperable within
seconds. In some cases sediment or lime build up around an element can eventually cause an air pocket,
resulting in a dry fired element. When element replacement is required, be sure tank is full of water prior to
energizing the water heater.
2. Grounded Element. In most cases, an element with a short circuit to ground will cause the circuit breaker in
the service panel to open or shut off. In some cases there may not be enough current draw for the circuit
breaker to open. This will allow the heating element to be in continuous operation resulting in overheated
water, limited only by the Hi Limit Switch located in the thermostat circuit. Repeated actuation of the Hi Limit
Switch usually is the result of a grounded heating element.
3. Sediment build up. Slow hot water recovery can usually be traced back to sediment or lime build up around
heating element. Sediment build up can also over time cause a dry fired element.
If a heating element is found to be inoperative, it must be replaced. Follow service procedure IX on page 21.
The illustration below shows a common “Screw-In” type heating element identifying certain features commonly referred to
throughout this manual.