Bradford White MII120A-SCF Service Manual

Save this manual for future referenceManual 238-47174-00BSERVICEMANUALTroubleshooting Guideand Instructions for Service(To be performed ONLY byqualifi

SEQUENCE OF OPERATIONMII Series Commercial Electric Water Heaters can use either immersion thermostat (contactor models) orsurface mounted thermostats

SEQUENCE OF OPERATIONSequence of Operation:Surface Mounted Thermostats.ORTerminal BlockFuse BlockLine VoltageHeating ElementSurface MountedThermostatL

SEQUENCE OF OPERATIONSequence of Operation:600V Surface Mounted Thermostats (w/Contactors).Line voltage is applied across terminals of fuse blockor a

TROUBLESHOOTINGMost common cause for improper electric water heater operation can be linked to heating elementfailure.When troubleshooting an electric

SYMPTOM PROBABLE CAUSE CORRECTIVE ACTIONNo Hot Water1. No power to heater.2. Blown water heater fuses.3. Loose wire connections.4. Inoperative heating

SERVICE PROCEDURE MCE-IHeating Element Testing1. STOP, DANGER! Turn power “OFF” to water heater.2. Remove access cover from lower control box. Remove

SERVICE PROCEDURE MCE-IILine Voltage TestingPage 16Line Voltage TestingIllustration 31. STOP, DANGER! Turn power “OFF” to water heater.2. Open upper c

SERVICE PROCEDURE MCE-IIIFuse TestingFuse Testing1. Turn “OFF” power to water heater.2. Open upper control box to allow accessto fuse block.3. Locate

SERVICE PROCEDURE MCE-IVHigh Limit (ECO) TestingPage 181. This procedure assumes line voltage and fuses are in working order.2. This procedure illust

SERVICE PROCEDURE MCE-VHigh Limit (ECO) TestingPage 191. This procedure assumes line voltage, transformer, fuses, and thermostat are in working order

Table of ContentsPage Service ProcedureIntroduction ………………………………………………………………………. 2 - - -Tools……………………………………………………………………………… 2 - - -General Informat

SERVICE PROCEDURE MCE-VIHigh Limit (ECO) TestingPage 20High Limit Control (ECO) Testing forContactor Models1. Determine if Hi-Limit has actuated. Thi

SERVICE PROCEDURE MCE-VIIThermostat TestingIllustration 8Water In Tank Is Cold With Power ON.1. This procedure assumes line voltage, ECO andelements a

SERVICE PROCEDURE MCE-VIIIThermostat TestingWater In Tank Is Cold With Power ON.1. This procedure assumes line voltage, ECO, transformer thermostat, a

SERVICE PROCEDURE MCE-IXThermostat TestingImmersion Thermostat Operation TestingThermostat Control Continuity Testing.1. This procedure assumes line v

SERVICE PROCEDURE MCE-XContactor TestingContactor Operation TestingNoisy or chattering contactor operation in most cases is due to voltage variations

SERVICE PROCEDURE MCE-XContactor TestingPage 25Contactor Operation Testing (continued)This procedure assumes control circuit is operating correctly.Pr

SERVICE PROCEDURE MCE-XIThermostat Removal and ReplacementFront ViewThermostat MountingSurface Mounted Thermostat Removal1. STOP, DANGER! Turn power “

Immersion Thermostat Removal & Replacement1. STOP, DANGER! Turn power “OFF” to water heater.2. Turn off cold water supply to heater. Connect hose

SERVICE PROCEDURE MCE-XIIIContactor Model High Limit (ECO) Control Removal and ReplacementPage 28Contactor Model High Limit (ECO) ControlRemoval and R

SERVICE PROCEDURE MCE-XIV600V Model High Limit (ECO) Control Removal and ReplacementPage 29600V Surface Thermostat ModelHigh Limit (ECO) ControlRemova

GENERAL INFORMATIONBradford White MII Series Commercial Electric water heaters can be manufactured with a choice between twodifferent types of thermos

SERVICE PROCEDURE MCE-XVHeating Element Removaland ReplacementHeating Element Removal1. STOP, DANGER! Turn power “OFF” to water heater.2. Turn off col

Page 31WARNINGHeater components and stored water may be HOT when performing the following steps inthis procedure. Take necessary precaution to prevent

Page 32Generic Parts List32

Generic Parts ListItem Description1 Anode.2 Hot Water Outlet Nipple.3 T&P Nipple.3A T&P Coupling.4 T&P Relief Valve.5 High Limit Switch.5A

NOTESPage 3434

NOTESPage 3435

[email protected]@bradfordwhite.comwww.bradfordwhite.com

Page 4GENERAL INFORMATIONUpperControl BoxLowerControl BoxGround LugTerminal BlockFuse Block(s)Contactor(s)High Limit (ECO) ControlImmersion Thermosta

Page 5GENERAL INFORMATIONUpperControl BoxLowerControl BoxGround LugTerminal BlockContactor(s)Surface ThermostatsHeating ElementsHigh Limit (ECO) Contr

GENERAL INFORMATIONPage 6Surface Mounted ThermostatsManualECO (high limit)Reset buttonTemperaturecontrol DialSurface MountCombination Thermostat/ECO (

GENERAL INFORMATIONPage 7Surface Mounted Thermostats (w/Contactors) for600V Models600V models use contactors to deliver line voltage to the heating el

GENERAL INFORMATIONContactor1-½” HexScrew-in FlangeTerminal BlockScrewTerminal BlockZinc Plated Copper orIncoloy SheathElement Rating Ink Stampedon si

GENERAL INFORMATIONWattsVolts x 1.732Watts = Amps x VoltsVoltsWatts2Commonly Used Formulas240V 1PhUngroundedUngroundedGroundingBLACKREDGREEN240120Comm