Laars NeoTherm NTH Installation and operation instructions manual - page 22
LAARS Heating Systems
Page 22
SECTION 5.
Electrical Connections
WARNING
The appliance must be electrically grounded in
accordance with the requirements of the authority
having jurisdiction or, in the absence of such
requirements, with the latest edition of the National
Electrical Code, ANSI/NFPA 70, in the U.S. and with
latest edition of CSA C22.1 Canadian Electrical Code,
Part 1, in Canada. Do not rely on the gas or water piping
to ground the metal parts of the boiler. Plastic pipe or
dielectric unions may isolate the boiler electrically.
Service and maintenance personnel, who work on or
around the boiler, may be standing on wet floors and
could be electrocuted by an ungrounded boiler.
Electrocution can result in severe injury or death.
Single pole switches, including those of safety
controls and protective devices must not be wired in a
grounded line.
All electrical connections are made on the terminal
blocks that are located inside the control panel.
NOTE: All internal electrical components have been
prewired. No attempt should be made to connect
electrical wires to any other location except the terminal
blocks.
Wiring connections are shown in
Figure 21.
5.1 Main Power
Connect a minimum 15A fused, 120-volt supply to
the main power switch (hot leg is connected directly to
switch). Neutral leg is connected directly to the white
wire. Ground wire can be connected to the grounding
lug in the box.
5.2 Control Features
The NeoTherm boiler control is a versatile control
that interfaces with a user display. The user display
allows access to many features of the control for setup,
diagnostics and operation. There are three menu
structures to choose from, USER
USER
USER
USER
USER mode, SETUP
SETUP
SETUP
SETUP
SETUP mode, and
MENU ITEM
Outlet water temperature Displays the current outlet water
temperature and allows the setpoint
to be adjusted.
Inlet water temperature
Displays the current inlet water
temperature
Delta T
Displays the current Temperature
rise across the heat exchanger
DHW water temperature Displays the current DHW
temperature and allows the setpoint
to be adjusted
Stack Temperature
Displays the current stack
temperature
Outdoor Temperature
Displays the current Outdoor air
temperature
Firing Rate
Displays an indicator of the current
firing rate based upon fan RPM. The
actual firing rate may vary.
Table 10. User Mode Menu Structure.
DIAGNOSTIC
DIAGNOSTIC
DIAGNOSTIC
DIAGNOSTIC
DIAGNOSTIC mode. Each mode will give the user access to
different types of information. The menus are accessed
by using the buttons located on the display.
5.2.1 User Mode
USER
USER
USER
USER
USER mode is the home screen shown on the
control. To navigate from item to item within USER
USER
USER
USER
USER
mode press the
NEXT
button. If a menu that is user
adjustable is selected, such as outlet or DHW the
UP
or
DOWN
arrows can be used to adjust the temperature
setpoint. Once the correct value is selected the
DONE
button can be pressed to select the adjusted values. The
USER
USER
USER
USER
USER mode menu structure and information that is
available is shown in
Table 10
.
5.2.1.1
Temperature Control Point
Adjustment
To adjust the temperature control point, confirm
the display is in USER
USER
USER
USER
USER mode and the outlet temperature is
being displayed. Press the
UP
or
DOWN
arrow to adjust
the control point temperature. The control point
temperature is measured at the outlet of the heat
exchanger. When making adjustments make sure the
control point is set far enough away from the high limit
to keep the temperature rise of the heat exchanger from
causing nuisance high limit tripping problems.
5.2.1.2
Domestic Hot Water Control Point
Adjustment
To adjust the DHW temperature control point,
confirm the display is in USER
USER
USER
USER
USER mode. Scroll through the
menu structure using the
NEXT
button until the current
DHW temperature is being displayed. Use the
UP
or
DOWN
arrow to adjust the setpoint to the desired value.
Press the
DONE
button when complete.
5.2.2 Setup Mode
SETUP
SETUP
SETUP
SETUP
SETUP mode is accessed by holding the
UP
and
DOWN
arrow keys simultaneously for 3 seconds. SETUP
SETUP
SETUP
SETUP
SETUP
mode allows the parameters listed in
Table11
to be
adjusted by using the
NEXT
button to select the
parameter to be adjusted and then the
UP
or
DOWN
Figure 17. Control Buttons on User Interface.