Hubbell JHX User manual

INSTALLATION, OPERATION, AND
MAINTENANCE MANUAL FOR
THE HUBBELL MODEL JTX / JHX
TANKLESS BOOSTER HEATER
ELECTRIC HEATER COMPANY
* The Hubbell Model JTX is designed for use with conveyor and flight type dish
machines. This product is not intended for use with door style dish machines.
Edition 2012A

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HUBBELL
ELECTRIC HEATER COMPANY
P.O. BOX 288
STRATFORD, CT 06615-0288
PHONE: [phone]
FAX: [phone]
INTERNET: http://www.hubbellheaters.com
Important Safety Information
1. You must read and follow all instructions. Serious bodily injury or death could occur
if you ignore this warning.
2. All circuit breakers and/or disconnect switches servicing the heater must be turned off
when installing, uninstalling, or repairing this booster heater.
3. The Hubbell Tankless Booster Heater must be grounded.
4. The unit must be installed by a licensed electrician and plumber.
5. The unit must be wired in accordance with the current version of the National
Electrical Code (US) or Canadian Electric Code (Canada).
6. This installation must comply with all national, state, and local plumbing and
electrical codes.
7. When the heater is not within sight of the electrical circuit breakers, an additional
local means of disconnection of all ungrounded conductors must be provided that is
within sight of the appliance or a circuit breaker lockout must be used. (Ref. NEC
422.31)
8. Water Quality Requirements – Recommended water hardness is 4 to 6 grains of
hardness per gallon (GPG). Water hardness above 6 GPG should be treated by a
water conditioner (water softener or in-line treatment). Water hardness below 4 GPG
also requires treatment to reduce potential corrosion. Excessive GPG will result in
higher operating and maintenance costs and will reduce product longevity. Chlorides
must not exceed 50 parts per million (ppm). Excessive chlorides will result in
metallic corrosion and will reduce product longevity. Water treatment has been
shown to reduce costs associated with de-liming the booster as well as reducing
metallic corrosion. Product failure caused by these conditions is not covered under
warranty. See warranty for complete details.
9. The booster heater is factory set at 185°F for booster water heating applications. This
results in the possibility of a scalding water injury. A full thickness skin burn can
occur in less than one second of exposure to water at this temperature.
10.*Disclaimer: The Hubbell Model JTX is designed for use with conveyor and flight
type dish machines. This product is not intended for use with door style dish
machines.

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TABLE OF CONTENTS
SECTION TITLE PAGE No.
I TANKLESS BOOSTER HEATER OPERATING PRINCIPLE 4
II GENERAL DESCRIPTION AND CONSTRUCTION 5
III INSTALLATION 9
IV OPERATION AND MAINTENANCE 23
V TROUBLESHOOTING 29
VI SERVICING & REPLACEMENT OF PARTS 36
VII PARTS LIST 40
VIII WARRANTY 41

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SECTION I – TANKLESS BOOSTER HEATER OPERATING PRINCIPLE
How the Hubbell Tankless Booster Heater Works:
For the most part, operating the new tankless booster heater is very similar to using any
traditional booster heater system. However, it is very important that all of the set-up
procedures and operating instructions are carefully read to ensure maximum performance
and energy savings from the new water heater.
The Hubbell Tankless Booster Heater does not store hot water like a conventional tank-type
booster heater. It contains high powered heating elements that are capable of heating water
instantly on-demand as needed. As soon as there is a hot water demand, a sophisticated flow
sensor within the heater recognizes the demand and initiates the heating process. This
sensor measures the water flow rate while two other sensors measure the incoming and
outgoing water temperature. This information is transmitted continually to the
microprocessor controller which determines the precise amount of power to send to the
heating elements to heat the water to the desired temperature. The Hubbell tankless booster
heater only uses as much power as is needed to meet the demand by fully modulating the
heating elements from 0 to 100%.
It is important to keep in mind that all tankless booster heaters are subject to a maximum
flow rate. If this flow rate is exceeded, the heater will not be capable of fully heating water.
The amount of water that can be heated by the tankless booster heater at any given time will
depend on the model selected and the incoming water temperature. See the charts in Section
II to determine the maximum flow rates.
Moreover, since a tankless booster heater eliminates the ongoing thermal losses caused by
storing hot water in a tank, there will be a significant energy savings compared to a
conventional tank type booster heater.
*Disclaimer: The Hubbell Model JTX is designed for use with conveyor and flight type
dish machines. This product is not intended for use with door style dish machines.

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Heating Elements
Heating ChamberHi-Limit Switches
Inlet Thermistor
Outlet Thermistor
Element Switching
Devices (Triacs)
Temperature
Controller
LED Digital Display
(with buttons)
Power Distribution Block
Ground Lug
Hot Water
Outlet
Warm
Water Inlet
Drain
Flow Meter
Magnetic
Contactor
Transformer
Control Fuse
SECTION II –GENERAL DESCRIPTION AND CONSTRUCTION
Technical Specifications Common to All Models:
Materials: Copper Exchanger /
Stainless Steel Casing Plumbing
Connection:
Low
Flow ¾” Copper Sweat
Energy
Efficiency: 98% High
Flow 1” Copper Sweat
Voltage: 208-600 Volts Operating Range: 5 – 150 psi
Frequency: 50 / 60 Hz Protection: Thermal Auto Reset
Product Overview:
Notes:
1. Power distribution blocks are only installed on single phase models.
2. Magnetic contactors are only installed on 3-phase models.
3. Transformers are only installed on 3-phase models over 240 volts.
4. 2-Element models will have a plug in the lowest element chamber and have only two hi-
limit switches and triacs installed.
Typical 2/3-Element Model

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Heating Elements
Inlet Thermistor
(beneath triac
plate)
Outlet Thermistor
Element Switching
Devices (Triacs)
Temperature
Controller
LED Digital Display
(with buttons)
Magnetic Contactor
Ground Lug
Hot Water
Outlet
Warm
Water Inlet
Drains
Flow Meter
Hi-Limit Switches Heating Chamber
Transformer
Power
Distribution
Bl
ock
Control Fuse
Notes:
1. Power distribution blocks are only installed on single phase models and 3-phase models
that require two magnetic contactors. Single phase models use a 2-pole power
distribution block.
2. Magnetic contactors are only installed on 3-phase models. One or two magnetic
contactors may be installed as required.
3. Transformers are only installed on 3-phase models over 240 volts.
Typical 6-Element Model

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Tankless Booster Heater Maximum Flow Rates:
5°F 10°F 20°F 30°F 40°F 50°F 60°F 70°F 80°F 100°F 120°F 140°F
810.9 5.5 2.7 1.8 1.4 1.1 0.9 0.8 0.7 0.5 0.5 0.4
11 15.0 7.5 3.8 2.5 1.9 1.5 1.3 1.1 0.9 0.8 0.6 0.5
12 16.4 8.2 4.1 2.7 2.1 1.6 1.4 1.2 1.0 0.8 0.7 0.6
13 17.8 8.9 4.4 3.0 2.2 1.8 1.5 1.3 1.1 0.9 0.7 0.6
14 19.1 9.6 4.8 3.2 2.4 1.9 1.6 1.4 1.2 1.0 0.8 0.7
15 20.5 10.3 5.1 3.4 2.6 2.1 1.7 1.5 1.3 1.0 0.9 0.7
16 21.9 10.9 5.5 3.6 2.7 2.2 1.8 1.6 1.4 1.1 0.9 0.8
18 24.6 12.3 6.2 4.1 3.1 2.5 2.1 1.8 1.5 1.2 1.0 0.9
20 27.3 13.7 6.8 4.6 3.4 2.7 2.3 2.0 1.7 1.4 1.1 1.0
21 28.7 14.4 7.2 4.8 3.6 2.9 2.4 2.1 1.8 1.4 1.2 1.0
24 32.8 16.4 8.2 5.5 4.1 3.3 2.7 2.3 2.1 1.6 1.4 1.2
25 34.2 17.1 8.5 5.7 4.3 3.4 2.8 2.4 2.1 1.7 1.4 1.2
27 36.9 18.5 9.2 6.2 4.6 3.7 3.1 2.6 2.3 1.8 1.5 1.3
30 20.5 10.3 6.8 5.1 4.1 3.4 2.9 2.6 2.1 1.7 1.5
31 21.2 10.6 7.1 5.3 4.2 3.5 3.0 2.6 2.1 1.8 1.5
33 22.6 11.3 7.5 5.6 4.5 3.8 3.2 2.8 2.3 1.9 1.6
36 24.6 12.3 8.2 6.2 4.9 4.1 3.5 3.1 2.5 2.1 1.8
40 27.3 13.7 9.1 6.8 5.5 4.6 3.9 3.4 2.7 2.3 2.0
42 28.7 14.4 9.6 7.2 5.7 4.8 4.1 3.6 2.9 2.4 2.1
48 32.8 16.4 10.9 8.2 6.6 5.5 4.7 4.1 3.3 2.7 2.3
50 34.2 17.1 11.4 8.5 6.8 5.7 4.9 4.3 3.4 2.8 2.4
54 36.9 18.5 12.3 9.2 7.4 6.2 5.3 4.6 3.7 3.1 2.6
Maximum Flow Rate (GPM) at Tem
p
erature Rise (°FΔT)
Power (kW)
1. Shaded values indicate that a High Flow (JHX) unit is required.
2. Blank values indicate that the flow rate will exceed the flow capability of the flow meter.
3. For alternate power (kW) values, the maximum flow rate can be calculated using the
formulas on the following page.
Tankless Low Flow Pressure Drop Chart (JTX):

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Tankless High Flow Pressure Drop Chart (JHX):
Wattage De-rating Formula:
Applied Voltage2× Rated Wattage = Actual Wattage
Rated Voltage2
For example: If installing a 27 kW unit when actual voltage is 212 V,
2122= 44,944 = 0.78 × 27,000 W = 21,060 W @ 212 V
240257,600
Amperage Formula:
Watts = Amps (Single Phase) Watts ÷1.73 = Amps (3-Phase)
Volts Volts
Flow Rate Formulas:
To determine power (kW) requirement
____GPM × ____ °F ΔT × 0.1465 = ____ kW
To determine temperature rise
____ kW × 6.824 ÷ ____ GPM = ____°F ΔT
To determine flow rate
____ kW × 6.824 ÷ ____ °FΔT = ____ GPM

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SECTION III – INSTALLATION
WARNING: Serious bodily injury or death may occur if the following warnings are
ignored.
• All circuit breakers and/or disconnect switches servicing this heater must be turned
off before installing, repairing or uninstalling this water heater.
• Installation of this product is restricted to indoor locations.
• Installation MUST be done by a licensed electrician and licensed plumber.
• *Disclaimer: The Hubbell Model JTX is designed for use with conveyor and flight
type dish machines. This product is not intended for use with door style dish
machines.
Locating and Mounting Instructions:
The Hubbell tankless booster heater can be installed just about anywhere. Due to the small
size of the water heater, it can be mounted in many small spaces. However, there are some
important guidelines to follow that will ensure that the installation is both safe and
convenient in the event that future servicing is required.
This product is designed to be installed indoors only. The unit may be installed in an
outdoor location as long as it is mounted in a suitable enclosure that protects it from rain,
direct sunlight, debris, and insects. This product should NOT be installed in a location where
it may be subjected to freezing temperatures. If the water inside the tankless booster heater
freezes, it can cause severe and permanent damage that is not covered under the warranty. If
you suspect that the tankless booster heater may have frozen, do not turn on the heater until
it has thawed and it has been inspected for leaks.
When selecting an installation location, give consideration to the existing plumbing
configuration, location of your main electrical panel, and location of the point of use. Try to
choose a location that does not require major plumbing alterations, that is close to the main
electrical panel (this will reduce the amount of wire needed to install), and that is physically
close to the dish machine. By locating the heater close to the dish machine, this will reduce
the amount of time it takes for the hot water to travel from the water heater to the point of
use. Consideration should also be given to future servicing. Do NOT locate the water heater
in a location that is difficult to access. Do NOT install above electrical boxes or junctions.
Mounting the unit:
•Leave a minimum of 12” to both sides and 4” on the top and bottom of the unit.
•Mount the booster heater securely to the wall by putting four (4) screws through the
mounting holes.
•Install a ¼” diameter bead of sealing caulk around the entire perimeter of the heater
between the heater back panel and the wall. This prevents any moisture or debris
from accumulating.

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