Weil-McLain 4 Series Manual page 31

sTeam series
94
Figure 21 Water level control locations
M3 M3
J1 J1
Secondary
water
level
control
J5 J5
Bottom of Bottom of
gauge glass gauge glass
M4 M4
Blowdown Blowdown
valve valve
Normal water line
is at the center of
the gauge glass
LEFT
SIDE
O N D
S E C
550-100-157/0523
boiler manual
4
M1 M1
A
B
M2 M2
RIGHT
SIDE
A R Y
P R I M
A R Y
Primary Casting line
Water height above
Primary
Level bottom of
water
Control gauge glass
level
control
Note 1
61, 63
Blowdown Blowdown
valve valve
93, 193, 94
(Note 3)
51-2
51-S-2
1"to 1-1/4"
(Note 3)
Notes:
1 Other manufacturers' controls providing similar functions
may be used if properly located and selected
2 Use LWCO function only Pump controller function must
only be handled by the primary control
3 When the pump control is used with a feedwater tank,
install the pump control on the boiler and the makeup
water feeder on the tank Use a separate LWCO on
the boiler when back-up is needed Do not install a
combination LWCO with feeder as a back-up control on
boiler The feeder will operate before the pump control
operates
Lowest Acceptable
Operating Water Level
1/4" above bottom of
Lowest Permissible
Water Level 1" below
visible portion of
230055
insTallaTion
Backup Casting line
Water height above
Level bottom of
Control gauge glass
"A"
Notes 1, 2
1/4" None
1/2" 61, 63
2" None
2" 93, 193, 94
2" 61, 63
51-2
(1494 to
1594 only)
2"
– or –
51-S-2
(all sizes)
None
Gauge Glass
Gauge Glass
550-430-732_0113
1
2
"B"
—
1/4"
—
3
1/4"
1/4"
4
1/4"
—
5
6
7
8
31