Xylem McDonnell & Miller SA91-30B User manual

• Before using this product read and understand instructions.
• Save these instructions for future reference.
• All work must e performed y qualified personnel trained in the proper
application, installation, and maintenance of plum ing, steam, and electrical
equipment and/or systems in accordance with all applica le codes and ordinances.
• To prevent a fire, do not exceed the switch contact rating.
Failure to follow this warning could cause property damage, personal injury or
death.
WARNING CAUTION
!
WARNING
Terminal Panel
Switch Arm Contact
Electrical Ratings
Models with 5 or 5-M Switch
Switch Ratings
Burner Valve
120 VAC 345 VA 0 - 135 ohms @ 24 VAC
240 VAC
Models with 7B or 7B-M Switch
Pump and Burner Switch Contact Ratings
Voltage Pilot Duty Only
120 VAC 345 VA
240 VAC
Replacement Pump and Burner
Switch Arm Contacts with
Terminal Panel
SA91-30B
SA91-30P
For installation on 5, 5-M, 7B or 7B-M
Switch Assem lies
INSTRUCTION MANUAL
MM-714C

2
OFF
ON
STEP 1 - Removal and Replacement of Contacts and Terminal Panels
a. Turn power off to boiler and all controls.
Allow boiler to cool to 80˚F (27˚C) and
reduce the pressure to 0 psi (0 bar).
BURNER
SWITCH
LEVER
STOPS
A
C
E
TOWER TUBE
FITTINGHUB
SWITCH
HOUSING
TERMINAL
CONNECTIONS
SWITCH
COVER
PUMP
TERMINAL
PANEL
BURNER
TERMINAL
PANEL
CONDUIT
CONNECTOR
NAMEPLATE
NAME PLATE
BASE 
PLATE
B
D
. Remove Switch Assem ly, Terminal
Panels and Switch Housing
• Remove two screws (A) and lift off switch
cover.
• Identify terminal connections for rewiring
and then disconnect all wires from terminal
panels.
• Remove conduit connector and wire from
integral fitting hu .
• Remove four hex nuts (B) and carefully lift
switch assem ly up and off tower tu e.
• Remove two screws (C) and remove
nameplate.
• Loosen and remove four screws (E) that
hold pump and urner terminal panels in
place. Do not remove terminal panels at
this time.
• Reach through nameplate opening and hold
urner switch lever about midway
between upper and lower stops to move
contact arms into correct (upright) position.
ith contact arms in upright position, carefully
remove urner terminal panel.
• Reach through nameplate opening and hold
pump switch lever about midway
between upper and lower stops to move
contact arms into correct (upright) position.
ith contact arms in upright position, carefully
remove pump terminal panel.
• Loosen four screws (E) and carefully lift
switch housing up off ase plate.
There may e more than one source of power to
the oiler.
!
CAUTION

3
NOTCH NOTCH
5 / 5-M
TERMINAL PANEL
ORIENTATION
24
1
BLUE RED
3
31
42
A
C
E
TOWER TUBE
FITTINGHUB
SWITCH
HOUSING
TERMINAL
CONNECTIONS
SWITCH
COVER
PUMP
TERMINAL
PANEL
BURNER
TERMINAL
PANEL
CONDUIT
CONNECTOR
NAMEPLATE
NAME PLATE
BASE 
PLATE
B
D
d. Replace Switch Housing, Switch
Assem ly and Reconnect Wiring
• Replace switch housing and fasten to
ase plate with four screws (E).
•
Move burner switch arms to upright position
by reaching through nameplate opening
and holding urner switch lever midway
between stops. Carefully set urner
terminal panel in position and fasten with
screws (D). Do not force. (See diagram at
lower right for proper orientation of
terminal panel).
•
Move pump switch arms to upright position
by reaching through nameplate opening
and holding pump switch lever midway
between stops. Carefully set pump
terminal panel in position and fasten with
screws (D). Do not force. (See diagram
at lower right for proper orientation of
terminal panel).
• Check visually to see that contact arms
are in proper position between terminal
panel contacts and move lever up and
down to see that switch operates freely
and smoothly.
• Carefully slide switch assem ly over
tower tu e and secure with four hex
nuts (B).
• Install conduit connector and wires to
the integral fitting hu on switch
assem ly.
• Reconnect wiring to terminal panel in
exactly the same position as removed.
• Replace switch cover and fasten with
two screws (A).
• Replace nameplate and fasten with
two screws (C).
F
GH
I

c. Remove and Replace Switch Arm Contacts
• Remove two screws (F) and lift off bus bar
(G), contact arms (H) and insulator (I).
• Place new insulator (I), contact arms (H) and
bus bar (G) in position and fasten with two
screws (F). Make sure the contact arm blades (H)
are in alignment and at right angle to insulator.
Proceed to Step 2 to Test Control

STEP 2 - Testing
a. Turn on power to oiler and pump circuits.
ith the boiler empty, the pump should turn on (5 or 5-M switch models) or the valve open
(7B or 7B-M switch models). The burner should remain off and boiler should begin to fill with water.
. For Automatic Reset Models
hen water level in the gauge glass is approximately 1 3/8” (35mm) above the horizontal cast line,
the burner should turn on.
For Manual Reset Models
hen water level in the gauge glass is approximately 1 3/8” (35mm) above the horizontal cast line,
press the manual reset button and the burner should turn on.
c. For 5 or 5-M Switch Models
hen water level in the gauge glass is approximately 2 1/8” (54mm) above the horizontal cast line,
the pump should turn off.
For 7B or 7B-M Switch Models
hen water level in the gauge glass is approximately 2 11/16” (68mm) above the horizontal cast
line, the valve should be closed.
d. ith the water in the boiler at its normal level and burner on, SLO LY open the blow-down valve
until it is fully open. As the water level in the gauge glass begins to drop, verify that the following
occurs.
For 5 or 5-M Switch Models
hen water level drops to approximately 1 1/8” (29mm) above the horizontal cast line, the pump
should turn on.
hen water level drops to the horizontal cast line, the burner should turn off.
For 7B or 7B-M Switch Models
As the water level drops, the valve should begin to open.
hen the water level drops to approximately 7/8” (22mm) above the horizontal cast line, the valve
should be full open.
hen the water level drops to the horizontal cast line, the burner should turn off.
e. Close the blow-down valve after burner turns off and restore water level to normal operating level.
f. Repeat testing procedure several times to ensure proper operation of control.
g. After testing and verification of control operation, the boiler can be returned to service.
– Dimensions shown are typical.
– The following testing procedure is only meant to serve as a verification of proper
operating sequence.
CAUTION
Immediately turn off all power if the urner turns on with no water in the gauge glass.
Investigate further efore continuing procedure.
!
CAUTION
If pump does not turn off or valve close, turn off water supply to oiler. Investigate
further efore continuing procedure.
!
McDonnell & Miller
Xylem Inc.
8200 N. Austin Avenue
Morton Grove, Illinois 60053
Phone: [phone]
Fax: [phone]
www.mc onnellmiller
McDonnell & Miller is a tra emark of Xylem Inc. or one of its subsi iaries.
© 2013 Xylem Inc. MM-714C January 2013 Part No. 210422