IBC SL 26-260 G3 - Page 33

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INSTALLATION
SL 26-260 G3, SL 40-399 G3 MODULATING GAS BOILERS
Compared with the Primary/Secondary approach, the above design saves one pump. Lost
is the simplicity of constant head and ow at the boiler.
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 ow.
To ensure adequate water ow 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 ow rate might drop below minimum requirements (20 gpm).
For further information and details, consult our Application Notes – which provide detail on
specic single and multiple boiler applications “Piping”, “Wiring” and “Settings”. (available
at www.ibcboiler.com or from your IBC Representative).