IBC SL 20-160 G3 Installation And Operating Instructions Manual page 38

NOTE
For further information and
details regarding Multiple
Boiler application, consult our
Technical Notes - Multiple Boiler
Systems. These notes provide
necessary detail on specific
single and multiple boiler
applications "Piping", "Wiring"
and "Settings". (available at
www.ibcboiler.com or from your
IBC Representative).
1-30
SL 10-85 G3, SL 14-115 G3, SL 20-160 G3, SL 30-199 G3 MODULATING GAS BOILERS
Check valves or thermal traps should be used to isolate both the supply and return piping
for each load - to avoid thermal siphoning and reverse flow.
To ensure adequate water flow through the boiler under high-head / single zone space
heating conditions, a pressure activated bypass or other means of bypass must be used
on any load where the flow rate might drop below minimum requirements.
For further information and details, consult our Application Notes – which provide detail on
specific single and multiple boiler applications "Piping", "Wiring" and "Settings". (available
at www.ibcboiler.com or from your IBC Representative).
Multiple boiler piping - Benefits and installation rules
Multiple IBC boilers can be installed in a single heating system to provide redundancy,
increased output, and greater heating plant turn-down capabilities. Primary/Secondary
piping must be employed, and each boiler must be installed with its own pump as
illustrated below. This approach provides constant head and flow at each boiler,
regardless of flow variations in the main building loop.
Each boiler will control its own pump, turning it off or on when heat is required. This
approach saves electricity by reducing the pumping power required as load conditions are
reduced. One boiler control is set up as a "Master" boiler, and up to 23 additional boilers
can be added to the system as "Subordinate" boilers by connecting a twisted pair of wires
between the boilers. No additional controls are needed.
Check valves are to be used in each boilers piping to prevent reverse flow when the boiler
is off.
For further information and details, consult our Application Notes – which provide detail on
specific single and multiple boiler applications "Piping", "Wiring" and "Settings". (available
at www.ibcboiler.com or from your IBC Representative).
Figure 40: Multiple boiler piping concept
INSTALLATION AND OPERATION INSTRUCTIONS