Unit System Operation; General - IBC SFC-99 Installation And Operating Instructions Manual

BOILER SYSTEMS AND OPERATION
SFC COMBI BOILERS SFC-99, SFC-125

2.0 UNIT SYSTEM OPERATION

2.1 GENERAL

The SFC series modulating condensing units are designed to heat both your
indoor space and your domestic hot water. The unit's unique heat exchanger
design incorporates separate copper waterways for space heating and for
domestic hot water generation.
With the installation of the provided outdoor sensor, the unit's controller can
provide outdoor reset control for the space heating load. The built-in control
provides a set point for water temperature for the domestic load. Installing the
outdoor sensor is optional, but recommended for higher efficiency.
Alternatively, the controller can provide a set-point water temperature for the
space heating load.
The unit is equipped with a factory-installed pump. The pump is pre-wired and
will operate with any call for space heating and when heating an IBC indirect
water heater. The pump will not operate with a call for domestic hot water using
the unit's internal domestic hot water tankless coil.
The unit pump operates for 10 seconds every 24 hours to prevent it from seizing.
The pump is energized 24 hours after the last call for heat and every 24 hours
after that until the next call for heat.
The SFC series unit can generate domestic hot water in several ways. The SFC
series unit can be used as a tankless water heater, with or without a storage tank,
and also with an IBC indirect water heater.
The unit is equipped with an electronic unit controller that ignites the burner and
continuously monitors the flame throughout each call for heat. The control also
displays the current operating conditions of the unit and any error messages
should a problem occur.
The unit's controller also provides frost protection. When the unit's heat
exchanger temperature becomes too low the burner switches on to keep the heat
exchanger warm. Ensure that the condensate trap is protected from freezing. The
unit must be installed indoors.
DANGER
° Water temperature over 125°F (52°C) can cause severe burns instantly
or death from scalds.
° Children, disabled, and elderly are at highest risk of being scalded.
° See instruction manual before setting temperature at water heater.
° Feel water before bathing or showering.
° Temperature limiting valves are available, see manual.
HOT
BURN
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