Xylem MM 413F Replacement Head Mechanism With Switch Assembly: 93-HD, 93-M-HD, 93-7B-HD, 93-7B-M-HD, 94-HD 94-M-HD 94-7B-HD 94-7B-M-HD - Manual (Page 3)

3
OFF
ON
STEP 1 - Preparation
INSTALLATION – TOOLS NEEDED:
One (1) flathead screw driver, one (1) scraper and
one (1) 9/16" socket box or open end wrench.
a. Turn power off to boiler and all controls.
FLOAT
CHAMBER
b. Allow boiler to cool to 80˚F (27˚C) and
reduce pressure to 0 psi (0 bar).
Drain water in boiler to a level that is
below the float chamber.
There may be more than one source of power to
the boiler.
! CAUTION
TOWER TUBE
SWITCH
ASSEMBLY
SWITCH
COVER
TERMINAL
PANELS
CONDUIT
CONNECTOR
FITTING
HUB
B
A
a. Disconnect and Remove Wires.
For Replacement Heads with Switches
(-HD Models)
• Remove two screws (A) and lift off switch
cover.
• Identify terminal connections for rewiring
and then disconnect all wires from
terminal panels.
• Remove conduit connection and wires
from integral fitting hub.
For Replacement Heads without Switches
(-HDLS Models)
• Remove four hex nuts (B) and carefully lift
switch assembly up and off tower tube.
STEP 2 - Head Removal