Xylem MM 235E Replacement Snap Switch Assembly SWA 150S 150S MD 158S 159S - Manual

INSTRUCTION MANUAL
MM-235E
For Series 150S and 157S Low
Water Cut-Off/Pump Controllers
(All Models)
Replacement Snap Switch Assembly
SWA-150S SWA-158S
SWA-150S-MD SWA-159S
• Before using this product read and understand instructions.
• Save these instructions for future reference.
• All work must be performed by qualified personnel trained in the proper application, instal-
lation, and maintenance of plumbing, steam, and electrical equipment and/or systems in
accordance with all applicable codes and ordinances.
• To prevent serious burns, the boiler must be cooled to 80˚F (27˚C) and the pressure must be
0 psi (0 bar) before servicing.
• To prevent electrical shock, turn off all sources of electrical power before servicing unit.
• This low water cut-off must be installed in series with all other limit and operating controls
installed on the boiler. After servicing unit, check for proper operation of all of the limit
and operating controls before leaving the site.
• We recommend that secondary (redundant) Low Water Cut-Off controls be installed on all
steam boilers with heat input greater than 400,000 BTU/hour or operating above 15 psi of
steam pressure. At least two controls should be connected in series with the burner
control circuit to provide safety redundancy protection should the boiler experience a
low-water condition. Moreover, at each annual outage, the low water cutoffs should be
dismantled, inspected, cleaned, and checked for proper calibration and performance.
• To prevent a fire, do not use this low water cut-off to switch currents over 7.4A, 1/3 Hp at
120 VAC or 3.7A, 1/3 Hp at 240 VAC, unless a starter or relay is used in conjunction with it.
Failure to follow this warning could cause property damage, personal injury or death.
WARN ING
CAUT ION
! WARNING
Replacement Switch Assembly