Weil-McLain GOLD CGS 550-110-260/02002 - Manual (Page 14)

Part number 550-110-260/0200
14
GOLD CGs Gas-Fired Water Boiler
Water piping — general information
3a
General piping information
If installation is to comply with ASME or Canadian requirements, an
additional
high temperature limit is needed. Install control in supply
piping between boiler and isolation valve. Set second control to minimum
20 °F above setpoint of first control. Maximum allowable setpoint is 240 °F.
See section
9b , page 32 for wiring.
A low water cutoff device is required when boiler is installed above
radiation level or by certain state or local codes or insurance companies.
Use low water cutoff designed for water installations. Electrode probe-
type is recommended. Purchase and install in tee in supply piping above
boiler.
Use backflow check valve in cold water supply as required by local codes.
Relief valve
Install relief valve vertically in ¾" tapping on side of boiler. See Figure 4
or 5 and the tag attached to the relief valve for manufacturer’s instructions.
To avoid water damage or scalding due to relief valve
operation:
• Discharge line must be connected to relief valve outlet and run to a
safe place of disposal . Terminate the discharge line to eliminate
possibility of severe burns should the valve discharge.
• Discharge line must be as short as possible and be the same size as
the valve discharge connection throughout its entire length.
• Discharge line must pitch downward from the valve and terminate at
least 6" above the floor drain where any discharge will be clearly visible.
• The discharge line shall terminate plain, not threaded, with a material
serviceable for temperatures of 375 °F or greater.
• Do not pipe the discharge to any place where freezing could occur.
• No shutoff valve shall be installed between the relief valve and boiler,
or in the discharge line. Do not plug or place any obstruction in the
discharge line.
• Failure to comply with the above guidelines could result in failure of
the relief valve to operate, resulting in possibility of severe personal
injury, death or substantial property damage.
• Test the operation of the valve after filling and pressurizing system
by lifting the lever. Make sure the valve discharges freely. If the valve
fails to operate correctly, replace it with a new relief valve.
System water piping
See Figure 4 (diaphragm-type or bladder-type
expansion tank) or Figure 5 (closed-type expansion
tank) on page 15, and Table 3 below, for near-boiler
and single-zone systems designed for return water at
least 130 °F.
See pages 16-17 to complete multiple-zone piping or
pages 18-23 to complete piping for radiant heating
systems or converted gravity systems.
Refer to page 23 for boilers used with refrigeration systems.
Install boiler such that —
• Chilled medium, if used, is piped in parallel with
heating boiler. Use appropriate valves to prevent
chilled medium from entering boiler. Consult
I=B=R Installation and Piping Guides.
• If boiler is connected to heating coils located in air
handling units where they can be exposed to
refrigerated air, use flow control valves or other
automatic means to prevent gravity circulation
during cooling cycle. Circulation of cold water
through the boiler could result in damage to the
heat exchanger, causing possible severe personal
injury, death or substantial property damage.
Pressure/temperature gauge
Install pressure/temperature gauge in tee on supply piping (as shown in
drawing on page 3). The gauge well is a self-closing valve, allowing removal
of the gauge without draining the system.
Slowly remove pressure/temperature gauge from well.
The self-closing valve could leak if clogged with
sediment. If water begins to spray, stop removing gauge.
Close system fill valve and drain enough water to release
system pressure before continuing with gauge removal.
Escaping hot water could cause severe personal injury.
Circulator
The circulator is shipped loose (wiring pre-attached
to boiler) to allow you to locate it either in the return
or supply piping, as desired. See page 3 for a typical
installation. Pipe the expansion tank to the suction side
of the circulator whenever possible. Install an air
separator in the supply piping. Connect the expansion
tank to the air separator only if the separator is on the
suction side of the circulator. Always install the system
fill connection at the same point as the expansion tank
connection to the system.
Figures 4 and 5 show typical
near-boiler piping connections.
Table 3 Water pipe size (based on 20 °F rise)
Boiler
model
number
To
system
From
system
CGs-3 1" 1"
CGs-4 1" 1"
CGs-5 1" 1"
CGs-6 1 ¼" 1 ¼"
Note: Circulator flange supplied with boiler is same size as
recommended piping above.