Hubbell D User Manual

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OPERATING AND MAINTENANCE MANUAL FOR ELECTRIC STAINLESS STEEL HEATER

FOR DEIONIZED (DI) WATER

ELECTRIC HEATER COMPANY

BASE MODEL “ D ”

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.Safety relief valve must be installed in tapping provided.

4.The refractory material used in heating elements may absorb some moisture during transit, periods of storage, or when subjected to a humid environment. This moisture absorption results in a cold insulation resistance of less than twenty(20) megohms. If this heater has been subjected to the above condition, each heating element must be checked for insulation resistance before energizing. A low megohm condition can be corrected by removing the terminal hardware and baking the element in an oven at 350°F -700°Ffor several hours or until the proper megohm reading is obtained.

5.KEEP AWAY FROM LIVE ELECTRICAL CIRCUITS.

Do not perform any maintenance, make any adjustments, or replace any components inside the control panel with the high voltage power supply turned on. Under certain circumstances, dangerous potentials may exist even when the power supply is off. To avoid casualties, always turn the power supply safety switch to off, turn the charge or ground the circuit before performing any maintenance or adjustment procedure.

6.The unit is designed to operate at pressure not more than 150 psi.

7.Generalized instructions and procedures cannot anticipate all situations. For this reason, only qualified installers should perform the installations. A qualified installer is a person who has licensed training and a working knowledge of the applicable codes regulation, tools, equipment, and methods necessary for safe installation of an electric resistance water heater. If questions regarding installation arise, check your local plumbing and electrical inspectors for proper procedures and codes. If you cannot obtain the required information, contact the company.

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TABLE OF CONTENTS

 

SECTION

TITLE

PAGE #

I

GENERAL DESCRIPTION AND CONSTRUCTION

5

II

INSTALLATION

9

III

SCHEDULED MAINTENANCE AND OPERATION

12

IV

TROUBLESHOOTING

14

V

SERVICING AND REPLACEMENT OF PARTS

16

VI

MISCELLANEOUS CHARTS AND FORMULAS

23

3

4

SECTION I - GENERAL DESCRIPTION AND CONSTRUCTION

GENERAL DESCRIPTION

This booklet describes an electric heater designed specifically for use in deionized (DI) water applications. The complete assembly consists of a type 316L stainless steel storage tank, type 316L stainless steel immersion electric heating element(s), thermostat, safety relief valve, safety high temperature cut out, magnetic contactor(s), and any other required electrical operating control. Optional equipment may be supplied with your unit. Please consult the product drawing for details specific to your assembly. The unit is factory assembled, insulated, jacketed, wired, tested, and ready for electrical and plumbing service connections.

CONSTRUCTION
TANK

The storage tank is constructed of type 316L stainless steel for maximum tank longevity. The tank is formed by all welded construction and is designed for a maximum allowable working pressure of 150 psi (300 psi TP). As an optional, the tank may be supplied with a passivated / electropolished finish.

TANK CONNECTIONS

The heater is supplied with separate connections for the cold water inlet and the hot water outlet. Water entering the cold water inlet is deflected by means of a baffle within the tank. A ¾-inchFNPT connection is provided for mounting a combination safety temperature and pressure relief valve. An overflow line should be utilized from the relief valve outlet to a floor drain. See drawing for locations and sizes.

HEATING ELEMENT

The water heater is supplied with an electric immersion heating element assembly(s), composed of type 316L stainless steel sheathed elements that are welded into a stainless steel flange. Each assembly is fastened to a corresponding tank flange using a Teflon gasket and four (4) 3/8-16x1-inchlong hex head steel bolts and nuts. See drawing for voltage and power ratings.

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CONTROL THERMOSTAT

The water heater is supplied with a single stage immersion thermostatic switch that is installed and wired at the factory. The thermostat can be adjusted through a range of 100° - 195° F, (an optional low range, 30° - 110° F, is available), and is adjustable with a flat tip screwdriver. Other thermostatic controls are available, see Options below.

TEMPERATURE HIGH LIMIT SWITCH

As a safety device, either a surface mounted high temperature cut-offswitch with manual reset, factory set at 205° F, or an optional immersion high temperaturecut-offswitch with manual reset, adjustable through a range of 100° - 240° F, is provided. In the event of anover-temperaturecondition, the thermostat will disengage the power from the system. The high limit must be manually reset thereafter to restart the heater.

 

Manual Reset

Surface Mounted High

 

Temperature Cut-OffSwitch

Immersion High Temperature Cut-OffSwitch

MAGNETIC CONTACTOR

The magnetic contactor(s) is a heavy-dutyresistive load type rated for 100,000 cycles. The contactor supplies power to the heating element(s) based on the resistive load(non-inductive)of the heater only when the thermostatic switch is engaged, thereby pulling in the contacts until the desired temperature is reached. At this point, the contacts will drop out, which in turn disconnects power from the elements. Magnetic contactors are installed only on units rated greater than 6kW.

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OUTER SHELL AND INSULATION

The tank is encapsulated in 2-inchesofhigh-densityfiberglass insulation. The protective shell is constructed of galvaneel and is coated with a durable silver hammertone finish.

OPTIONS

The following optional features may be included in your water heater. Reference included drawing specific to your heater for further details.

Low Water Cut-Off

Used as a safety device, the float type (316 stainless steel) low water cut-offis used to detect a low water situation and disengage the

operating coils in the magnetic contactor(s). Once the condition is remedied, the low water cut-offswitch is automatically reset. This type of low watercut-offuses a 316 stainless steel float.

Fused Low Voltage Transformer

A fused low voltage transformer may be supplied. This option is provided only in 480-voltsystems with low watercut-offsto step down the voltage to240-voltfor safety when working with control circuits. As an option, a transformer may be installed on any unit to step down the voltage to120-volts

Stainless Steel Outer Jacket

An optional stainless steel outer jacket may replace the standard galvaneel jacket.

Optional Connections

Flanged inlet and outlet connections (150#)

Threaded inlet and outlet connections (1 ½”, 2” MNPT)

Sanitary Connections

NEMA 4 or NEMA 4X Electric Control Panel

A NEMA 4 control panel may be supplied to provide watertight construction for installation in “wet” areas.

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Individually Fused Elements

To prevent the possibility of damage to control circuits and other elements in case of electrical overloads, fuses may be supplied for each circuit. Two types of fuses may be used; a type NON for voltages less than 250-voltor type JJS for voltage less than600-volt.

Type JJS

Type NON

Digital Display

A 1/16 DIN electronic temperature control package may be installed. A separate manufacturer’s operating manual will be supplied with the unit.

Stainless Steel Pressure-OnlyRelief Valve

Optionally, a ¾” NPT, type 316 stainless steel pressure-onlyrelief valve may be supplied, as shown below.

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SECTION II – INSTALLATION

WARNING / CAUTION

DO NOT TURN ON THE ELECTRIC POWER 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, the heating elements will burn out.

For protection against excessive pressures and temperatures, local codes require the installation of a temperature-and-pressure(T&P) relief valve certified by a nationally recognized laboratory that maintains periodic inspection of production of listed equipment of materials, as meeting the requirements for Relief Valves and Automatic Gas Shutoff for Hot Water Supply Systems. ANSIZ21.22-1971.THE CUSTOMER IS RESPONSIBLE TO PROTECT PROPERTY AND PERSONNEL FROM HARM WHEN THE VALVE FUNCTIONS.

All water heaters have a risk of leakage at some unpredictable time. IT IS THE CUSTOMER'S RESPONSIBILITY TO PROVIDE A CATCH PAN OR OTHER ADEQUATE MEANS, SO THAT THE RESULTANT FLOW OF WATER WILL NOT DAMAGE FURNISHINGS OR PROPERTY.

WATER HEATER PLACEMENT

1.Place the heater on a solid foundation in a clean, dry location nearest to the point of hot water use.

2.The water heater should be protected from freezing and waterlines insulated to reduce energy and water waste.

3.Leave a minimum of 18” clearance for element withdrawal, if necessary.

4.Do not install in an area where flammable liquids or combustible vapors are present.

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.Connect the cold water inlet and hot water outlet to the appropriate connections as shown; refer to the drawing for location and sizes.

2.Install the combination temperature and pressure safety relief valve in the tapping provided. Note that this is required by law for safety considerations.

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Outlet to floor drain

Install into provided tapping

Manual Release

Lever

Temperature Probe

Temperature and Pressure Relief Valve

3.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.

FILLING THE HEATER

1.Open the pressure relief valve test lever to allow air to escape.

2.Open the valve to the cold water inlet and allow the heater and piping system to completely fill, as indicated by a steady flow of water from the relief valve.

ELECTRICAL INSTALLATION

1.Enter electric enclosure with properly sized feeder leads. Single-phaseinstallations require two (2) leads; three phase installations require three (3) leads.

2.Install these power leads into the box lugs on the terminal block or magnetic contactor. See wiring diagrams below.

3.Torque screws per torque chart included in Section VI.

4.All other electrical connections are made at the factory; therefore, no other electrical connections are necessary.

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THERMOSTAT SETTING (BULB AND CAPILLARY IMMERSION TYPE)

The bulb and capillary type thermostat is immersed in a Type 316L stainless steel well in the storage vessel. The full thermostat range is 100-240°F,but should not be operated over 195°F. There is a setting screw, which can be locked at a particular setting to prevent an operator from turning the dial beyond a determined temperature point. To change the locking set screw open the thermostat cover and follow the printed directions on the inside of the cover. To change the operating temperature setting on the thermostat within the allowed range simply insert a screwdriver in the slot and make the appropriate adjustment to the temperature setting according to the desired point on the dial.

FINAL CHECKS

1.Check all connections for tightness.

2.Ensure that all the above steps are completed

3.After the water is heated for the first time, monitor the water temperature as described in Section III, Quarterly Inspection.

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SECTION III - SCHEDULED MAINTENANCE AND OPERATION

WARNING / CAUTION

Before performing any maintenance procedure, make certain power 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.

FREEZING

The tank should be fully drained in the event the electricity has been turned off and if there is danger of freezing.

QUARTERLY INSPECTION

1.Monitor thermostat

a.Let water heater completely heat to a designated thermostat setting.

b.After thermostat satisfies (that is, when the thermostat actually clicks off), draw water from heater.

c.Compare water temperature of drawn water to the temperature setting of the thermostat when it satisfies. Normal variation between the two points is approximately + 5°F.

d.If these two readings do not coincide within acceptable tolerances and verification has been made of the accuracy of the temperature-readinggauge, replace the thermostat.

2.Lift test lever on relief valve and let water run through valve for a period of approximately 10 seconds. This will help flush away any sediment that might build up in water passageways.

3.Inspect element flange for leakage as follows:

a.Shut off Power Supply.

b.Remove element housing cover.

c. Visually inspect heating element gasket for evidence of leaks.

d.Rub finger around gasket that is between the heating element and tank flange for any evidence of moisture. If moisture is present or a water drip is observed, follow procedure outlined in Section V.

4.Check for loose electrical connections. Tighten as necessary.

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ANNUAL INSPECTION

1.Flush tank as follows

a.Shut off power supply.

b.Close valve on hot water outlet piping.

c.Open valve on drain piping.

d.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 3-4minutes.

e.Close drain valve.

f.Open hot water valve.

g.Turn power supply ON.

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SECTION IV – TROUBLESHOOTING

Symptom

Probable Cause

Corrective Action / Remedy

No hot water

Circuit breaker tripped at source.

Reset circuit breaker.

 

Blown fuse in transformer, if

Replace fuse.

 

installed.

 

 

Circuit breaker at control cabinet

Reset circuit breaker.

 

tripped, if installed.

 

 

Blown fuse in element fuse block,

Replace fuse.

 

if installed.

 

 

High limit switch tripped.

Reset high limit switch.

 

 

 

 

Loose wires.

Tighten wires. Torque screws

 

 

per torque chart included in

 

 

Section VI.

 

Heating element inoperable.

Check heating element

 

 

operation by clamping an

 

 

Amprobe around each wire to

 

 

the element. The ampere

 

 

reading should agree with the

 

 

nameplate ‘AMP’ figure.

 

Low line voltage.

Have source electrical system

 

 

checked by an electrician.

 

Faulty thermostat.

Move thermostat dial through

 

 

full range. A definite ‘click’

 

 

should be heard. If not, replace

 

 

thermostat.

 

Faulty low water cut-off,if

Check to see if tank is full of

 

installed.

water. If not, fill tank. If problem

 

 

continues and tank is full, check

 

 

for continuity between the

 

 

common and normally open

 

 

contact of the relay board. If

 

 

continuity is not observed,

 

 

replace low water cut-off.

 

Magnetic contactor does not

Replace complete magnetic

 

energize.

contactor. Because of the design

 

 

of this particular contactor, it is

 

 

more desirable to replace

 

 

complete control rather than

 

 

rebuilding coil, contacts and

 

 

springs, etc.

 

 

 

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Water temperature below

Faulty thermostat.

Check thermostat adjustment.

settings at all times

 

Monitor thermostat as described

 

 

in Section III, Quarterly

 

 

Inspection. Replace if necessary.

 

Heating element not working on all

Check to see that heating

 

phases

element is working on all

 

 

phases, by checking the

 

 

resistance (ohms) value for each

 

 

element and comparing with the

 

 

chart included in Section VI.

 

Blown fuse in element fuse block,

Replace fuse.

 

if installed.

 

 

Heater improperly sized

Verify heater is properly sized

 

 

for the flow rate and temperature

 

 

rise of your system. See formulas

 

 

included in Section VI. Replace

 

 

elements with proper size as

 

 

necessary.

Relief valve discharges

Excessive temperature or pressure

Temperature and pressure relief

continuously

in tank

valves are made to operate if the

 

 

water temperature exceeds

 

 

210°F or water pressure exceeds

 

 

the pressure rating of the safety

 

 

relief valve. If trouble is

 

 

excessive temperature, then

 

 

thermostat is not shutting off at

 

 

the right setting and thermostat

 

 

must be replaced.

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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.

SURFACE TEMPERATURE HIGH LIMIT CUT-OFF

1.Disconnect power from unit.

2.Remove access cover.

3.Disconnect the four (4) 14 gauge wires.

Control Wires

4. Remove the two (2) mounting screws.

Mounting Screws

5.Replace control and install new high limit switch by performing above steps in reverse order. See wiring diagram included with drawing for assistance.

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IMMERSION TEMPERATURE HIGH LIMIT CUT-OFF

1.Disconnect power from unit.

2.Remove access cover.

3.Remove high limit cover screw and cover.

Cover

Cover Screw

Reset Switch

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. (Note: Be sure to place capillary tube into slot in base prior to installing cover.)

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HEATING ELEMENT

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.

7. Remove the 3/8-16nuts.

Tank Flange

Element Terminals

 

Nuts

8. Withdraw element assembly and remove gasket. Gasket

Element Assembly

9.Install new gasket and insert new heating element.

10.Rewire element according to the voltage and phase rating of the unit as shown below.

11.Fill tank and check around gasket for any leaks.

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IMMERSION THERMOSTAT

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) 14 gauge wires.

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.)

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