9
PN 240012960 REV. F [09/15/2020]
HYDRAULIC CONNECTIONS
• Clean the pipes of any debris, rust, incrustations, lime scale, welding slag and any other contaminants. The
hydraulic circuit must be clean.
• The appliance includes four (4) G3/4 ISO 228-1 X 3/4" NPT pipe thread adapters and four (4) gaskets provided
loose in a parts bag.
•
Use the furnished adapters and gaskets to convert the four (4) G3/4 ISO 228-1 straight thread fittings on the frame
of the appliance to ¾” NPT. The adapters will serve as pipe unions for easy connection and to facilitate future
service.
• Make sure to use the gaskets on the G3/4 ISO 228-1 straight thread connections when installing the ¾” NPT
adapters. Otherwise it will leak.
NOTICE
Do not install 3/4" NPT pipe fittings directly on the G3/4 ISO 228-1 ISO connections. Use the furnished adapters.
•
When making the water connections, take care not to overtighten the threaded fittings. Over time this could cause
bursting with hydraulic leakage and damage to things and/or persons.
•
Make sure that all fittings are watertight.
• To allow for future maintenance operations without having to drain the CH and DHW circuits, it is manufacturer
recommended to install field supplied manual stopcocks (shown) and/or DHW service valves (not shown).
• Refer to all local codes and jurisdictional requirements for installation of anti-scald valves, relief valves and/or
domestic hot water expansion tanks.
• The two-way valve in the DHW module is closed when there is no call for domestic hot water, thus preventing
reverse CH flow through the DHW loop.
G3/4 ISO 228-1 Straight Thread
Optional Stopcocks (field supplied)
3/4" NPT Adapter
DHW Circuit:
•
Piping for the domestic water in and out should be adequately sized for the desired flow rates at each fixture.
•
The appliance includes a 3.2 gpm flow regulator factory installed in the DHW inlet to restrict DHW flow. This
prevents excessive DHW flow rates that would be beyond the capability of the appliance.
•
The 3.2 gpm flow regulator is recommended for use with boilers with Heating Capacities up to 132,000 Btu per
hour.
•
For larger boilers with higher Heating Capacities, and thus greater ability to produce hot water, a 5.3 gpm flow
regulator is furnished loose in the parts bag.
•
Instructions to remove and replace the flow regulator can be found in the Maintenance Section.
•
For very large boilers, the installer may choose to remove the flow regulator altogether.
NOTICE
When the system requires the domestic hot water circuit to have a device which prevents water expansion towards the
mains (non-return valve, meter, pressure reducer, etc.) it is necessary to install an expansion tank downstream of the
device.