Xylem McDonnell & Miller 51 Series Instruction Manual page 3

STEP 2 - Installation of the Models 51/51-2, 51-S/51-S-2 and 53/53-2
a. Using the criteria in Step 1,
determine the location of the
51/51-2, 51-S/51-S-2 or 53/53-2.
This applies when the gauge
glass is directly mounted in the
boiler or on a water column.
b. Use Figure 1 or Figure 2 as a
general guide.
c. Connect steam equalizing lines
to any available opening other
than steam flow line.
(Take off line).
d. Test the Model 51/51-2, 51-S/51-S-2 and 53/53-2 Before Turning it Over to the Owner
Open the blow-down valve while burner is operating. As the water level drops the feeder will begin to
add water. As the water continues to drop the burner will shut off (on the 51-2, 51-S-2 and 53-2 only).
Gauge Glass Mounted in the Boiler
1" Steam Equalizing Line
1" Crosses
Gauge Glass
Level
Mark
Lower
Gauge
Glass
1" Water
Equalizing Line
(Short as Possible)
Gauge Glass Mounted on a Water Column
1" Steam Equalizing Line (Short as Possible)
1" Crosses
Level
Mark
Water
Column
1" Water Equalizing Line (Short as Possible)
1" Minimum Blow-down Valve
Figure 1
(Short as Possible)
By-Pass
Normal Water Line
Feeder Casting Mark
(See Installation Location)
1" Minimum Blow-down
Valve for Feeder
Float Chamber
Figure 2
By-Pass
Cold City Supply
Normal Water Line
Feeder Casting Mark
(See Installation Location)
Connect to Return
Header on Boiler
Side of all Valves
1" Minimum Blow-down Valve
for Feeder Float Chamber
Cold City Supply
Swing Check Valve
Connect to Return
Header on Boiler
Side of all Valves
Swing Check Valve
3