Laars NEOTHERM NTH Series, Инструкция по установке и эксплуатации

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LAARS Heating Systems
7.C Pump Connections and Operation
The controller in the unit energizes the boiler pump contacts
when it receives a call for heat. Once the call for heat is
satisfied, the pump will remain on for the defined pump
overrun time.
The boiler pump terminals (located on TB5) are fed by
120V (violet and white wires) internally from the main power
supply. The maximum allowable current draw is 7.4 amps.
If the expected FLA is larger than 7.4, it is required to install
and use a separate pump contactor (not included).
The System and DHW pump contacts are dry contacts.
Appropriate voltage must be supplied to the System and
DHW pumps for proper operation. (
See Figure 16 .)
These pump connections are located on terminal block 5
(TB5) in the control panel (See Figure 33) 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.
Using on board power for additional pumps is acceptable
if the unit’s main power supply MOP does not exceed 18
amps. If this is anticipated, additional 120VAC circuits will
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.D Hydronic Heating Using External
Modulation Control
About External Control -
When this unit is used for hydronic heating with external
modulation control, a call for heat must be supplied to the
“T-T or Interlock” terminal. Once the call is supplied the
control starts the Boiler and System pumps and begins the
ignition process. Once in Run, the unit monitors the flame
signal, call for heat, safeties, and water temperatures.
The boiler setpoint is used to limit the maximum water
temperature leaving the boiler only. The modulation rate
is controlled by a 4-20mA signal supplied by an external
control. (This can also be 0-10Vdc using a converter -
Manufacturer part number CA006100.) When setting
up a system using an external control, take care to set
Anti-Short Cycle feature to prevent “hunting “ and possible
premature component failure.
7.E Optional Field Connections
Terminal block 8 (TB8) in the control panel is used for the
‘Safety Chain’ and for connecting optional components
such as low water cutoffs, flow switches, additional high
limits, and other field-supplied devices that must be
interlocked with the boiler. These are non-powered dry
contacts only. All safeties or end switches must be wired in
series by removing the supplied jumpers.
See Figure 16