Recommended oil supply systems, Wiring, 2 pipe system – Sterling QVOF User Manual
Page 6: Figure 7 figure 8 - intermittent operation

6
RECOMMENDED
OIL SUPPLY SYSTEMS
2 PIPE SYSTEM
Separated suction oil line must be used for second unit.
Return oil lines can be twinned together.
Correct line size for two pipe installation 1/2″ O.D. tubing.
Figure 6
Maximum allowable length of either intake or return line
in feet, including horizontal and vertical run.
Maximum line lengths shown above are calculated for
No. 2 oil at 60° and 3450 RPM pump speed.
Table A
“Lift” Installation Values
Distance “B”
Single
Two
Lift
Stage
Stage
0′
100′
100′
1′
100′
100′
2′
100′
100′
3′
100′
100′
4′
100′
100′
5′
100′
100′
6′
100′
100′
7′
99′
100′
8′
83′
100′
9′
68′
100′
10′
52′
100′
11′
42′
100′
12′
25′
100′
13′
—
100′
14′
—
100′
15′
—
100′
WIRING
Figure 7
Figure 8 - Intermittent Operation
RETURN LINE
B
SEE TABLE A
SUCTION LINE
OIL TANK
JUNCTION BOX
FUSER 9A
ENTRANCE
9A CM
LINE
FAN
BLACK
PRIMARY
CONTACT
THERMOSTAT
BLACK
BLACK
WHITE
BURNER
MOTOR
ORANGE
BLUE
WHITE
BURNER SERVICE
SWITCH
CAD
CELL
BLOWER
MOTOR
THERMOSTAT
TOGGLE
SWITCH
JUMPER
IN PLACE
WIRING
CABLE
FAN SIDE
LIMIT SIDE
TYPICAL
ENTRANCE
SWITCH
COMBINATION
CONTROL
TWO WIRE
CABLE
PRIMARY
CONTROL
AND IGNITION
TRANSFORMER
TO THERMOSTAT
TERMINALS ON
PRIMARY CONTROL
JUNCTION BOX
TYPICAL
FUSED SWITCH
CONNECT PRESSURE
SWITCH TO FUEL UNIT
GAGE PORT
1/8 NIPPLE OF LENGTH TO
CLEAR STRAINER COVER
1/8 TEE
1/8 PIPE PLUG
PRESSURE SWITCH
NORMALLY OPEN
MANUAL
BOOST PUMP
SWITCH
CLOSED –
OPEN –
CONTINUOUS OPERATION
OPERATES ONLY UPON
BURNER DEMAND
LOW VOLTAGE
TWO CONDUCTOR WIRE
SWITCH RELAY
LINE
VOLTAGE
POWER
SUPPLY
TO BOOST
PUMP
MOTOR