Hubbell SLN User Manual

OPERATING AND MAINTENANCE MANUAL FOR

COMMERCIAL SOLAR WATER HEATER

ELECTRIC HEATER COMPANY

BASE MODEL “SLN”

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 11

IV TROUBLESHOOTING 13

V SERVICING AND REPLACEMENT OF PARTS 15

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SECTION I - GENERAL DESCRIPTION AND CONSTRUCTION

GENERAL DESCRIPTION

This book describes a packaged solar water heater that is a stationary, self-contained 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. The water heater heats domestic potable
water by transferring heat from the solar loop (typically ethylene glycol) to the domestic water via an
immersion heating coil inserted into the water heater tank. 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, and tested.

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.

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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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.

THERMISTOR CLIP

The water heater is supplied with a thermistor clip located just above the heating coil tank flange for
attaching a sensing probe to the water heater tank. Temperature sensors and controls are not included
with the water heater.

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), composed
of a copper sheathed element(s) that are brazed into a brass flange. 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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