Weil-McLain GOLD CGS-4E - Manual (Page 14)

Part number 550-110-282/1108
14
GOLD CGs-4E Gas-Fired Water Boiler — Boiler Manual
Water piping — general information
3a
Table 3 Water pipe size (based on 20°F rise)
Boiler
model
number
To
system
From
system
CGs-4E
1” 1”
Note: The boiler supply and return connections, the return/
drain tee and the supply/gauge tee supplied with
the boiler are 1¼” NPT. One of the circulator flanges
supplied with the boiler is 1¼”. The other circulator
flange is the size of the recommended system piping
shown above.
General piping information
If installation is to comply with ASME or Canadian requirements, an ad-
ditional 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 34 for wiring.
A low water cutoff device is required when boiler is installed above ra-
diation 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.
Pressure/temperature gauge
Install pressure/temperature gauge in tee on supply piping (as shown in
drawing on page 3).
Relief valve
Install relief valve vertically in ¾” tapping on side of boiler. See Figure 4 or 5 ,
page 15, and the tag attached to the relief valve for manufacturer’s instructions.
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 instal-
lation. 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 , page 15, show typical near-
boiler piping connections.
System water piping
See Figure 4 (diaphragm-type or bladder-type expan-
sion 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 (large-volume
systems originally designed for circulation by natural
convection rather than a pump).
Chillers or air handling units :
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 au-
tomatic 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.
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 mate-
rial 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.