Xylem MM 414B Series 150E and 157E Low Water Cut-Off/Pump Controllers For Steam Boilers and Other Level Control Applications - Manual (Page 4)

4
If the control will be the primary low
water fuel cut-off, size the steam (top)
and water (bottom) equalizing pipe lengths
so that the horizontal cast line on the body
is 1
3 /
8
” (35mm) below the boiler’s normal
water level, but not lower than the
lowest safe permissible water level, as
determined by the boiler manufacturer.
OR
If the control will be the secondary low
water fuel cut-off, size the steam (top) and
water (bottom) equalizing pipe lengths so
that the horizontal cast line on the body is
at or above, the lowest safe permissible
water level, as determined by the boiler
manufacturer.
STEP 1 - Determine the Elevation at Which the
Low Water Cut-Off/Pump Controller Must be Installed
INSTALLATION –
TOOLS NEEDED:
Two (2) pipe wrenches, one (1) flatblade screw-
driver, and pipe sealing compound.
IMPORTANT: Follow the boiler manufacturer's
instructions along with all applicable codes and
ordinances for piping, blow down valve and water
gauge glass requirements.
1 3 / 8 "
STEAM EQUALIZING PIPE
VERTICAL EQUALIZING PIPE
NORMAL BOILER WATER LINE
AS A PRIMARY
LOW WATER CUT-OFF/PUMP
CONTROLLER
BURNER CUT-OFF LEVEL AT CAST LINE
LOWEST
PERMISSIBLE
WATER LEVEL
(35mm)
WATER
EQUALIZING
PIPE
BLOW DOWN VALVE
BLOW DOWN VALVE
STEAM EQUALIZING PIPE
VERTICAL EQUALIZING PIPE
BLOW DOWN VALVE
BURNER CUT-OFF LEVEL AT CAST LINE LOWEST
PERMISSIBLE
WATER LEVEL
BURNER OFF
WATER
EQUALIZING
PIPE
AS A SECONDARY
LOW WATER CUT-OFF/PUMP
CONTROLLER
BLOW DOWN VALVE