Hubbell T, T30-15, T40-15, T65-20, T80-20 Maintenance Manual

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: [phone]
FAX: [phone]

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. 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.

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

6. 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 8

III SCHEDULED MAINTENANCE AND OPERATION 12

IV TROUBLESHOOTING 15

V SERVICING AND REPLACEMENT OF PARTS 16

VI MISCELLANEOUS CHARTS AND FORMULAS 25

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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. The unit is factory assembled, insulated, jacketed, wired, tested, and ready for electrical
and plumbing service connections.

CONSTRUCTION

TANK

The standard storage tank is constructed of steel and internally lined with specially formulated
Hydrastone cement to a ½-inch minimum thickness. The tank is designed for a maximum allowable
working pressure of 150 psi (300 psi TP).

TANK CONNECTIONS

The heater is supplied with separate cold water and hot water connections. Water entering the cold
water inlet is deflected by means of a baffle within the tank. The hot water outlet includes a built in heat
trap to prevent hot water from radiating out from the heater. A ¾-inch FNPT connection is located on
the side of the heater for mounting a combination safety temperature and pressure relief valve. An
overflow line should be installed from the relief valve outlet to a floor drain. A ¾-inch GHT connection
is supplied for draining. See drawing for locations and sizes.

OUTER SHELL AND INSULATION

The tank is encapsulated in 2-inch thick polyurethane foam insulation. The insulation is protected by a
high impact non-corroding colorized composite protective jacket.

HEATING COIL

The water heater is supplied with a high quality, factory installed, high efficiency, single walled,
copper finned heating coil designed for a maximum working pressure of 150 psi. The tubing is
installed in a heavy-duty fabricated steel head with threaded NPT connections. Each assembly is
fastened to a corresponding tank flange using a gasket and hex head steel bolts and nuts. Double
walled tubing may be supplied as an option.

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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.

Control Thermostat

The water heater may be supplied with either a surface mounted or immersion thermostatic switch to
control the back-up electric heating system. See drawing for specific details. The surface mounted
thermostat can be adjusted through a range of 110° - 170° F. The immersion thermostat can be adjusted
through a range of 100° - 190° F. Both thermostats are adjustable with a flat tip screwdriver.

Surface Mounted Thermostat
Immersion Thermostat

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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.

Manual Reset

Surface Mounted High
Temperature Cut-Off Switch Immersion High Temperature Cut-Off Switch

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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.

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. ANSI
Z21.22-1971. 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 most
frequent hot water use. If the heater is to be raised off the floor, the entire bottom of the
heater should be supported by a solid surface.

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.

INSTALL THE HEAT EXCHANGER COIL

1. Remove the access panel. (See diagram below).

2. Insert the heat exchanger and align the holes in the cover plate with the slotted holes in the
flange. (Note: align heat exchanger pipe connections with the opening in the access panel.)

3. WARNING: THE NYLON BUSHINGS MUST BE IN THE OPENINGS BEFORE THE
BOLTS ARE INSERTED. FAILURE TO DO THIS WILL VOID THE WARRANTY.

4. Insert and secure the bolts to the nuts one at a time in the following manner.

a. Place the nut behind the slotted flange opening.
b. Hold the nut in place with one hand – insert the bolt with the other.
c. Thread the bolt into the nut and tighten.
d. Proceed to the next opening.
e. NOTE: BE SURE TO PLACE BOLTS IN ALL OF THE OPENINGS.

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