14
Combi
(continued)
83
Installation & Service Manual
Water piping
Field connections are to be made as represented in FIG. 14-3.
WARNING
Ensure that plumbing and electrical installation are complete and supply gas is turned OFF. On initial startup, bleed air from the
system with the manual air vent on the primary boiler heat exchanger, as well as the manual air vent on the DHW pump, while
flowing domestic water in excess of the flow switch setting until all air has escaped. Be sure to connect a hose to each air vent to
allow the air and water to properly exit the unit. This process will energize the DHW pump and enable purging of air from low
mass water carrying components.
Adjustment of the anti-scald device should be set to a safe temperature to prevent injury. The anti-scald device MUST be set so
that the outlet water temperature will never exceed 120°F.
Figure 14-3 Single Boiler - Primary Secondary w/Combi Piping Diagram
BOILER
BACKFLOW
PREVENTER
PRESSURE
REDUCING VALVE
PRESSURE
GAUGE
ANTI-SCALD
MIXING VALVE
(REQUIRED)
COLD
WATER
SUPPLY
TEMPERATURE /
PRESSURE
GAUGE
AIR
SEPARATOR
EXPANSION
TANK
BALL VALVE
(TYPICAL)
UNION
(TYPICAL)
PRESSURE
RELIEF VALVE
DRAIN POINT
(TYPICAL)
MAKE UP WATER
FROM
SYSTEM
NOT TO EXCEED 4 PIPE DIA OR MAX. OF 12" APART
BOILER
CIRCULATOR
SYSTEM
CIRCULATOR
TO
SYSTEM
SYSTEM SUPPLY
SENSOR
(OPTIONAL)
DRAIN
MAY SUBSTITUTE LOW LOSS HEADER
Y-STRAINER
(RECOMMENDED)
HOT
WATER
SUPPLY
IMG00254
FLOW SWITCH
FLOW
CHECK
EXPANSION
TANK
TEMPERATURE & PRESSURE
RELIEF VALVE (REQUIRED)
Please note that this illustration is meant to show system piping concept only, the installer is responsible for
all equipment and detailing required by local codes.
NOTICE
A field-supplied anti-scald device MUST be installed as shown in FIG. 14-3. Anti-scald devices must be
selected and installed in accordance to local codes. Failure to do so will result in scald or serious injury. The
Combi is capable of supplying domestic water greater than 120°F which may scald.