Water Piping - Weil-McLain GOLD CGI 2 SERIES Manual

GOLD CGi Gas-Fired Water Boiler — Boiler Manual
4a
Water piping — general information
General piping information
If installation is to comply with ASME or Canadian requirements, an ad-
ditional high temperature limit
between boiler and isolation valve. Set second control to minimum 0°F
above setpoint of first control. Maximum allowable setpoint is 40°F. See
Section 9b for wiring.
low water cutoff device
A 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.
backflow check valve
Use
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
or 17 , page 1, 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
safe place of disposal
possibility of severe burns should the valve discharge.
• Discharge line must be as short as possible and be the
the valve discharge connection
pitch downward
• Discharge line must
at least 6" above the floor drain where any discharge will be clearly
visible.
• The discharge line shall
rial serviceable for temperatures of 35°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
•
by lifting the lever. Make sure the valve discharges freely. If the valve
fails to operate correctly, replace it with a new relief valve.
0
is needed. Install control in supply piping
in cold water supply as required by local
. Terminate the discharge line to eliminate
throughout its entire length.
from the valve and terminate
terminate plain, not threaded
after filling and pressurizing system
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.
piping connections.
System water piping
Figure 16
See
sion tank) or
Table 6
and
designed for return water at least 130°F.
See pages -3 to complete multiple-zone piping or
pages 4-9 to complete piping for radiant heating
Figure 16
systems or converted gravity systems (large-volume
systems originally designed for circulation by natural
convection rather than a pump). See page 9 for boilers
used with refrigeration systems.
Table 6 Water pipe size (based on 20°F rise)
Boiler
model number
run to a
CGi-25
CGi-3, 4, 5
CGi-6, 7
same size as
CGi-8
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 sup-
plied with the boiler is 1¼". The other circulator flange
is the size of the recommended system piping shown
above.
, with a mate-
• 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.
Figures 16 and 17 show typical near-boiler
(diaphragm-type or bladder-type expan-
Figure 17
(closed-type expansion tank)
, for near-boiler and single-zone systems
To
system
¾"
1"
1¼"
1½"
Chillers or air handling units
Install boiler such that —
Part Number 550-110-710/0107
From
system
¾"
1"
1¼"
1½"
: