Weil-McLain Evergreen EVG 220 Manual page 41

®
gas
Install water piping
Figure 49
Flow rates for 0.04 feet head loss per foot of
pipe (140°F water)
Pipe size MAX Flow rate (GPM)
(inches)
@ 0.04 feet per foot
¾
3.9
1
7.1
1¼
16
1½
24
Install relief valve
1. Install relief valve in a reducing tee, NPT, 1½" x 1¼" x ¾" on
®
Evergreen 220 or 1½"x 1½"x ¾" on Evergreen
on the boiler supply piping tee (Figure 6, page 11). The
®
Evergreen
220, 299 and 300 boilers come shipped loose with
a 30 PSIG, 375 MBTU relief valve. The Evergreen
comes shipped loose with a 30 PSIG, 575 MBTU relief valve.
This boiler is capable of a pressure up to 80 PSIG. Please see
miscellaneous Parts & Kits section for Weil-McLain alternate
pressure components.
2. If using a relief valve with a rating higher than 30 psi, other
system components may require higher pressure rated equip-
ment such as pressure gauges and expansion tank. Consult
local requirements and other codes/standards for required
equipment, if needed.
3. Pipe the relief valve only as shown, in the location shown.
4. Connect discharge piping to safe disposal location, following
guidelines in the following
Install pipe unions (recommended)
Install pipe unions 1½" NPT on boiler supply and boiler return,
Figure 6, page 11. Installing unions in these locations will aid in
future service. Pipe unions are NOT included with the boiler.
Connecting to Heating Coils:
If the boiler piping system is connected to heating coils
located in air handling units where there may be exposed to
refrigerated air circulation then it must be equipped with flow
control valves or other automatic means to prevent gravity
circulation of the boiler water during the cooling cycle.
Part number 550-100-131/0120
-
fired water boiler
(continued)
Pipe size MAX Flow rate (GPM)
(inches)
@ 0.04 feet per foot
2
45
2½
75
3
140
4
290
®
299/300/399
®
399 boiler
WARNING
.
— 220/299/300/399 Boiler Manual
To avoid water damage or scalding due to
relief valve operation, as per local or state
codes
Install relief valve ONLY with the spindle vertical,
as shown in illustrations in this manual.
Discharge line must be connected to relief valve
outlet and run to a safe place of disposal. Ter-
minate the discharge line in a manner that will
prevent possibility of severe burns or property
damage should the valve discharge. Locate away
from the top of the boiler.
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 tempera-
tures 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.
Test the operation of the valve after filling and pres-
surizing 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.
Failure to comply with the above guidelines could
result in failure of the relief valve to operate, result-
ing in possibility of severe personal injury, death
or substantial property damage.
:
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