OPERATING AND MAINTENANCE MANUAL FOR COMMERCIAL INDIRECT POWERED WATER HEATER ELECTRIC HEATER COMPANY BASE MODEL “ T ”
HUBBELL ELECTRIC HEATER COMPANY P.O. BOX 288 STRATFORD, CT 06615 PHONE: (203) 378-2659 FAX: (203) 378-3593 INTERNET: http://www.hubbellheaters.com/ -- IMPORTANT -Always reference the full model number and serial number when calling the factory. WARNING / CAUTION 1. Tank is to be completely filled with water and all air is to be vented before energizing. 2. Due to the rigors of transportation, all connections should be checked for tightness before heater is placed in operation. 3.
TABLE OF CONTENTS SECTION TITLE PAGE # I GENERAL DESCRIPTION AND CONSTRUCTION 5 II INSTALLATION 8 III SCHEDULED MAINTENANCE AND OPERATION 12 IV TROUBLESHOOTING 15 V SERVICING AND REPLACEMENT OF PARTS 16 VI MISCELLANEOUS CHARTS AND FORMULAS 25 3
SECTION I - GENERAL DESCRIPTION AND CONSTRUCTION GENERAL DESCRIPTION This book describes a packaged boiler water powered indirect water heater that is a stationary, selfcontained unit. The complete assembly on a standard unit consists of the storage tank, immersion heating coil, and an ASME rated combination temperature and pressure safety relief valve. Optional equipment may be supplied with your unit. Please consult the product drawing for details specific to your assembly.
CONTROL THERMOSTAT The water heater is supplied with an immersion thermostatic switch. The thermostat can be adjusted through a range of 120° - 140° F. OPTIONAL BACK-UP ELECTRIC HEATING SYSTEM Back-up Electric Heating Element The water heater may be supplied with an electric immersion heating element assembly(s). Each assembly is fastened to a corresponding tank flange using a gasket and four (4) 3/8-16 x 1-inch long hex head steel bolts and nuts. See drawing for voltage and power ratings.
Temperature High Limit Switch As a safety device, either a surface mounted high temperature cut-off switch with manual reset, factory set at 190° F, or an immersion high temperature cut-off switch with manual reset, factory set at 180° F, may be provided. In the event of an over-temperature condition, the thermostat will disengage the power from the back-up electric heating system. The high limit must be manually reset thereafter to restart the heater.
SECTION II – INSTALLATION WARNING / CAUTION DO NOT TURN ON THE BOILER WATER SUPPLY to this equipment until heater is completely filled with water and all air has been released. If the heater is NOT filled with water when the power is turned on, damage to the heating coil may result.
PIPING INSTALLATION NOTE: The most effective means for preventing deterioration from accelerated corrosion due to galvanic and stray current is the installation of dielectric fittings/unions. The installation of these fittings is the responsibility of the installing contractor. 1. All integral components have been properly sized to meet design conditions. Piping to the unit should be sized to meet the design conditions, as dictated by good engineering practices. 2.
4. Install the combination temperature and pressure safety relief valve in the tapping provided. Note that this is required by law for safety considerations. Outlet to floor drain Install into provided tapping Manual Release Lever Temperature Probe Temperature and Pressure Relief Valve 5. Install a relief valve overflow pipe to a nearby floor drain. CAUTION: No valve of any type should be installed between the relief valve and tank or in the drain line.
ELECTRICAL INSTALLATION 1. Connect electrical wiring from boiler controls and circulator pump to immersion thermostat. 2. If supplied with a back-up electric heating element; enter electric enclosure with properly sized feeder leads. Be sure to properly ground the water heater. Install these power leads into the box lugs on the terminal block. 3. Torque screws per torque chart included in Section VI. 4.
SECTION III - SCHEDULED MAINTENANCE AND OPERATION WARNING / CAUTION Before performing any maintenance procedure, make certain boiler water and electric supply is OFF and cannot accidentally be turned on. MAINTENANCE AND OPERATION The water heater is automatic in its operation. It will maintain a full tank of water at the temperature setting of the thermostat. The water heater should not be turned on without first making sure that the tank is full of water and that all air has been released.
ANNUAL INSPECTION 1. Flush tank as follows a. b. c. d. Shut off power supply. Close valve on hot water outlet piping. Open valve on drain piping. Cold water inlet line pressure will be strong enough to flush sediment from the bottom of the tank out through the drain. Let water run for 3-4 minutes. e. Close drain valve. f. Open hot water valve. g. Turn power supply ON. 2. Units subject to fouling or scaling should be cleaned periodically.
SECTION IV – TROUBLESHOOTING Symptom Gradual loss of heating capacity. Overheating. Immediate loss of heating capacity. Excessive vibration. Water hammer. Probable Cause Tubes are fouled. Corrective Action / Remedy Clean tubes per Section III, annual scheduled maintenance. Excess silt in bottom of tank. Drain and flush tank per Section III , annual scheduled maintenance. Ruptured tube(s) in heating Remove / replace heating coil. coil. Thermostat needs adjusting.
BACK-UP ELECTRCIAL HEATER SYSTEM (if supplied) Symptom No hot water Probable Cause Circuit breaker tripped at source. High limit switch tripped. Loose wires. Heating element inoperable. Low line voltage. Faulty thermostat. Water temperature below settings at all times Faulty thermostat. Heating element not working on all phases Heater improperly sized Relief valve discharges continuously Excessive temperature or pressure in tank Corrective Action / Remedy Reset circuit breaker.
SECTION V - SERVICING & REPLACEMENT OF PARTS WARNING / CAUTION Before servicing or replacing any part make sure to turn the power supply switch to the OFF position. RELIEF VALVE 1. Disconnect power from unit. 2. Shut off incoming water and boiler water supply. 3. Lift test lever on relief valve to relieve pressure in tank. 4. Disconnect overflow piping. 5. Unscrew relief valve, remove assembly and replace with new one. 6. Connect overflow piping. 7. Turn on incoming water supply and check for leaks. 8.
HEATING COIL 1. 2. 3. 4. Disconnect power from unit. Shut off incoming cold and boiler water supply. Attach hose to drain connection. Lift manual release lever on relief valve to let air into system or break union on outgoing water line. 5. Drain water from tank. 6. Disconnect supply and return lines from heating coil. 7. Remove bolts securing the heating coil to the tank flange. Tank Flange Gasket Heating Coil Assembly Supply and Return Connections Bolts 8.
SURFACE TEMPERATURE HIGH LIMIT CUT-OFF (if supplied) 1. Disconnect power from unit. 2. Remove access cover. 3. Disconnect the four (4) 14 gauge wires or three (3) 14 gauge wires and a jumper, as required. Control Wires 4. Remove the two (2) mounting screws or disconnect from thermostat, as required. Mounting Screws 5. Replace control and install new high limit switch by performing above steps in reverse order.
IMMERSION TEMPERATURE HIGH LIMIT CUT-OFF (if supplied) 1. Disconnect power from unit. 2. Remove access cover. 3. Remove high limit cover screw and cover. Cover Cover Screw Reset Tab 4. Disconnect the two (2) 14 gauge wires. Wires Capillary Tube 5. Remove capillary tube and bulb from thermowell 6. Remove two (2) mounting screws. Mounting Screws 7. Remove control and install new high limit switch by performing above steps in reverse order.
HEATING ELEMENT (if supplied) 1. Disconnect power from unit. 2. Shut off incoming water supply. 3. Attach hose to drain connection. 4. Lift manual release lever on relief valve to let air into system or break union on outgoing water line. 5. Drain water from tank. 6. Disconnect the wires from the heating element terminals. Tank Flange Wires 7. Remove the 3/8-16 nuts. 8. Withdraw element assembly and remove gasket. Gasket Element Assembly Nuts 9. Install new gasket and insert new heating element. 10.
L1 L1 L2 L3 L2 1 3 2 1 3 2 4 1 4 2 1 2 1 3 2 Single Element Operation 1 4 2 3 Ø Open Delta Wiring for Simultaneous Operation 21
L1 1 2 L2 L1 3 4 1 1 2 3 4 1 4 4 2 2 1 1 2 2 Interlocked for Non-Simultaneous Operation 22 L2 Non-Interlocked for Simultaneous Operation
SURFACE MOUNTED THERMOSTAT (if supplied) 1. Disconnect power from unit. 2. Remove access cover and locate thermostat. 3. Disconnect the two (2) or three (3) 14 gauge wires and jumpers, as required. Control Wires 4. Remove two (2) mounting screws and disconnect from high limit cut-off, if required. Mounting Screws 5. Replace thermostat using the reverse procedure.
IMMERSION THERMOSTAT (if supplied) 1. Disconnect power from unit. 2. Remove access cover and locate thermostat. 3. Remove high limit cover screw and cover. Cover Cover Screw 4. Disconnect the two (2) or three (3) 14 gauge wires, as required. Wires Capillary Tube 5. Remove capillary tube and bulb from thermowell. 6. Remove two (2) mounting screws. Mounting Screws 7. Replace thermostat using reverse procedure. (Note: Be sure to place capillary tube into slot in base prior to installing cover.
SECTION VI – MISCELLANEOUS CHARTS AND FORMULAS FORMULAS 25
T Model – Coil Curves
