Xylem McDonnell & Miller MM-243D Instruction Manual

Replacement Head Mechanism
42S-HD
(Snap Switch)
Replacement head mechanisms can be installed without
disturbing existing equalizing connections or disassembly
of components, making repairs simple and easy.
• Before using this product read and understand instructions.
TI O N
C A U
N IN G
W A R
• 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 the electrical power before making electrical connections.
• This low water cut-off must be installed in series with all other limit and operating controls
installed on the boiler. After installation, check for proper operation of all of the limit and
operating controls, before leaving the site.
• To prevent serious personal injury from steam blow down, connect a drain pipe to the
control opening to avoid exposure to steam discharge.
• 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.
!
WARNING
INSTRUCTION MANUAL
Replacement Head Mechanism
MM-243D