Install Instructions
Page 26
LAARS Heating Systems
SECTION 7 ELECTRICAL AND
WIRING DIAGRAMS
BOILER PUMP CONNECTIONS
RATINGS
SIZES VOLTS PHASE AMPS (Boiler, System Pump and
DHW Pump Connections)
80–210 120 Single 2* 115V – Maximum 1HP
No Pump or 7.4A max
80-210 Less
With Pump 120 Single than
115V – Maximum 1HP
6*
or 7.4A max
*
Minimum 15A circuit required
Table 15. Boiler Electrical Data
7.B Main Power Connections
Connect a 15A fused, 120-volt supply to the main power
switch. (The hot leg is connected directly to the switch.)
The neutral leg is connected directly to the white wire. The
ground wire can be connected to the grounding lug on the
control panel. (See Figure 16.)
7.C Pump Connections and Operation
The controller in the unit energizes the pump contacts
when it receives a call for heat. Once the call for heat is
satised, the pump will remain on for the dened pump
overrun time.
The Boiler Pump terminals (TB5 - max 7.4 FLA) are fed by
120V (violet wire) internally from the main power feed. The
System and DHW contacts are dry contacts. Appropriate
voltage must be supplied to the System and DHW pumps
for proper operation.
The System pump connections are located on terminal
block 5 (TB5) in the control panel. (See Figure 16.) The
System pump contacts are rated for 120Vac, 7.4 Amps. To
use the contacts, power must be supplied on one terminal
with the other terminal wired to the pump or a relay
controlling the pump.
The DHW pump connections are located on terminal block
5 (TB5) in the control panel and are rated for 120Vac, 7.4
Amps. To use the contacts, power must be supplied on
one terminal, and the other terminal wired to the pump or a
relay controlling the pump.
Additional 120VAC circuits may be required for the pumps.
Once the unit has been installed and set up, the Quick
Start menu provides a simple way to change the most
common settings used in a typical installation. (If your
installation is more complex, refer to Section 8C.) To reach
the Quick Start menu, press the “I” button (“Info/Install”),
then press the Quick Start menu item.
7.A Installation Warnings
WARNING
This unit 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 the 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 oors
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.
Wiring connections are shown in Figure 16.
All internal electrical components have been prewired.
No attempt should be made to connect electrical wires
to any other location except the terminal blocks.
CAUTION
The supply voltage to the Unit must not be
disconnected, except for service or isolation, or
unless otherwise instructed by procedures outlined
in this manual. To signal a call for heat, use the
24V eld interlock, as shown in the wiring diagram.
DO NOT MAKE AND BREAK THE LINE
VOLTAGE TO THE UNIT TO SIGNAL A CALL FOR
HEAT. A call for heat/ end call for heat MUST be
connected to the eld interlock terminals. Some
components are designed to have constant voltage
during normal operation. If this units supply voltage
is toggled as a call for heat signal, premature
failure of these components may result.
This unit does not recognize 4mA as a signal
to shut o. If the call for heat is not connected
between the eld interlock terminals, the Unit
will remain in low re when it sees 4mA as a
modulating signal.