Power Quality And Electrical Protection; Zone Valve Hook-Up; Thermostat / Sensor Wiring - IBC SL 20-160 G3 Installation And Operating Instructions Manual

NOTE
The IBC boiler (like any modern
appliance that contains
electronic equipment), must have
a "clean" power supply, and is
vunerable to power surges and
spikes, lightning strikes and
other forms of severe electrical
"noise". Power conditioning
equipment (surge protectors,
APC or UPS devices) may be
required in areas where power
quality is suspect.
DANGER
Do not connect thermistor
sensors to "Therm" terminals.
An overheating hazard can result
in serious personal injury and/or
property damage.
NOTE
The IBC Touch-Screen controller
has the ability to connect to most
power stealing thermostats. See
the V-10 Touchscreen Boiler
Controller manual for details.
INSTALLATION
SL 10-85 G3, SL 14-115 G3, SL 20-160 G3, SL 30-199 G3 MODULATING GAS BOILERS
The boiler (primary) pump is connected to the White/Yellow pair labeled Primary Pump.
This lead is factory wired to the controller (and its 120 VAC supply) at the upper right
backside of the controller board. Do not attempt to connect the primary pump to the Pump/
Zone Valve Terminal Block along the controller's right edge - this is for the secondary
pumps and/or zone valves only. Connect the pump's Black wire to the Yellow of this
pair (switched Hot). The White/ Yellow pair should be individually capped if the primary
pump does not obtain its power from this pair (e.g. if a variable speed primary pump is
connected to the mains power).
Pumps can be switched on/off using the touchscreen controller, so there is no need for
temporary pump wiring during system filling / air purging.
In a new construction application, use a construction thermostat, or jumper with an in-line
on/off switch – for on/off management of the boiler. Do not just remove power from the
unit, or its moisture management routine will be interrupted (fan turns at ultra low rpm for
90 minutes after burner shutdown). Treat it like a computer, where you do not just pull the
plug when done. If an "Insufficient airflow / check vent" error signal shows, check for (and
remove) any water in the clear vinyl air reference tubes. This has been seen occasionally
at construction sites where the boiler has been repeatedly de-powered wet.
The combined current of all pumps connected through the on-board pump relays
should not exceed 10 amps. The control circuit board is protected using on-board field
replaceable fuses. Each pump is fused with a separate 5 Amp fuse. The Alarm contact
is fused with a 5 Amp fuse and the 24 VAC boiler control circuit is protected with a 2 Amp
fuse.
The VS output leads are not commonly used, except when providing a variable speed
signal to the fan in an IBC Air Handler.

1.8.2 Power Quality and Electrical Protection

In areas of unreliable power, appropriate surge protectors and or power conditioning
equipment should be installed in powers supply wiring circuits.

1.8.3 Zone Valve Hook-up

If zone valves rather than pumps are used to manage multiple heating loads, then 24 VAC
for the zone valves should be provided to the power contacts on the Pump/ Zone Valve
Terminal Block. Disconnect the 120 Vac leads connected to PV-L/PV-N and cap off. Use
a separate transformer – the 40 VA unit inside the wiring box is for internal systems only.
The individual load/zone valves are then to be wired to their associated contacts on the
secondary pump/zone valve connector. Do not confuse such "load/zone valves" with similar
valves used to segregate a single load type (e.g. those used on a zoned radiant floor) – see
the next section.

1.8.4 Thermostat / Sensor Wiring

Dry contacts for thermostats for each of the four loads are provided as marked on the lower
connector strip (e.g. "Therm 1"). Gang lines from a multiple-zoned load (e.g. off the end-
switches for each radiant floor zone) present a common thermostat signal to the controller.
Ensure there are no disturbing influences on the call-for-heat lines - e.g. no coils to switch
an air handler motor. Most power stealing thermostats can be connected directly to the
Therm terminals. See the V-10 Touchscreen Boiler Controller manual for more detailed
instructions.
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