Weil-McLain WM97+70 Manual page 13

WM97+ -
gas fired water boiler
Boiler hydrostatic test
Install pipe fittings for relief
Figure 6
valve and pressure/temperature
gauge —
DO NOT mount relief
valve until AFTER hydrostatic
testing
(see legend at right)
WM97+70 or WM97+110
TOP —
WM97+155
TOP —
Part number 550-142-085/0712
— Boiler Manual
(continued)
Install piping components required for hydrostatic test
Figure 7
(WM97+70/110 shown)
1 Boiler supply (outlet) connection, (male, 1" NPT on 70/110, 1¼" NPT on 155)
2 Boiler return connection, (male, 1" NPT on 70/110, 1¼" NPT on 155)
3 Boiler relief valve, shipped loose with boiler — DO NOT mount relief valve until AFTER
hydrostatic testing.
3a TEMPORARILY ONLY — Insert a ¾" NPT plug in the relief valve tapping of the street ell. This
MUST BE REMOVED after the test and the relief valve mounted here.
4 Pressure/temperature gauge, shipped loose with boiler
5 Street ell, ¾" NPT, shipped loose with boiler, for mounting boiler relief valve
For WM97+70 or 110, rotate the street ell to about 30° off center, as shown, to allow room for the relief
valve discharge piping.
6a Reducing tee, NPT, 1" x 1" x ¾" or 1¼"x1¼"x¾", shipped loose with boiler
6b Reducing tee, 1" x 1" x ¾" NPT or 1¼" x 1¼" x ¾", shipped loose with boiler
7 Nipple, 1" x close or 1¼" x close, shipped loose with boiler
8 1" NPT boiler water SUPPLY connection for DHW tank or CWH, if used. DO NOT use this connection for
any application except DHW or CWH.
9 1" NPT boiler water RETURN connection for DHW tank or CWH, if used. DO NOT use this connection for
any application except DHW or CWH.
10 1" NPT pipe cap, shipped loose with boiler — leave this in place if NOT connecting to DHW or CWH here;
remove after hydrostatic testing to connect boiler water supply if connecting DHW tank or CWH.
11 1" x ¾" NPT reducing coupling, shipped loose with boiler — remove after testing if DHW tank or CWH is
to be connected; leave in place if not connecting DHW tank or CWH.
12 isolation valve on return connection, by installer (1" NPT on 70/110, 1¼" NPT on 155)
13 isolation valve on supply connection, by installer (1" NPT on 70/110, 1¼" NPT on 155)
14 Street ells, by installer (1" NPT on 70/110, 1¼" NPT on 155)
15 Pipe nipple on supply outlet line, by installer — long enough to prevent dripping water on the boiler
(1" NPT on 70/110, 1¼" NPT on 155)
16 ¾" NPT boiler drain valve, shipped loose with boiler — after hydrostatic testing, move drain valve to low-
est point on the return piping if connecting to DHW tank or CWH; leave as shown if NOT using connection.
17 Pipe nipple on boiler return line, by installer — long enough to prevent dripping water on the boiler
(1" NPT on 70/110, 1¼" NPT on 155)
(see legend below)
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