MN702GE 060320
– 12 –
2. Pre-fire inspection • preparation
(continued)
Install gas train on burner
1. The standard burner gas train is shipped fully assembled, with the piping
disconnected at the gas train unions. See separate instructions if installing
an optional knocked down gas train. The gas train is available in either
an angled (standard) or straight (optional) configuration.
2. Connect the main trains at the unions (Figure 5).
To avoid damage to gas train components, do not hold compo-
nents with a pipe wrench or overtighten. Use only a crescent
wrench or other means. Failure to comply could result in severe
personal injury, death or substantial property damage.
3. Connect the flexible conduit, pre-attached to the burner J-box, to the gas
train J-box, and attach the wires to the terminal strip inside the gas train
J-box.
a.
Match wire colors of the incoming wires to those pre-wired to the
terminal strip inside the gas train J-box.
b.
See the label in the burner junction box included
Gas valve vent opening — The V48 diaphragm gas valve is
NOT fitted with a vent limiting orifice in the vent connection. If
local codes require, install piping from the vent connection to
outside, sized and installed as required by codes. Because this
is a diaphragm-assisted solenoid valve, a small amount of gas
will exit from the vent orifice each time the valve opens.
Figure 5
Gas train installation (shown with straight gas train)
Connect pilot gas train at union
Connect main gas train at union
Figure 5A
Gas piping schematic
GAS FUEL TRAIN
OIL FUEL TRAIN
Gas Input
F
A
A
FS
P
R
A
M
Test
To Main Burner
To Pilot Burner
J
R1
B
S
R2
S
C
S
Sediment Trap
Oil Supply
Connection
Oil Return
Connection
U
V
W
Y
HF
LF
FS Fuel Strainer
U
Oil Pressure Interlock Switch (if required)
HF High FIre Nozzle
V
Low Fire Safety Shutoff Valve
LF Low FIre Nozzle
W
High FIre Safety Shutoff Valve
P
Fuel Pump
Y
Fuel Pressure Gauge (if required)
R
Mechanical Shutoff Valve
A Manual Valve
B Firing Rate Valve
C Orifice
D Manual Reset Low Gas Pressure Switch (optional)
E
Manual Reset High Gas Pressure Switch (optional)
F
Gas Filter or Strainer (if required)
J
Leakage Test Valve
M Pipe Cap
R1 Main Gas Pressure Regulator
R2 Pilot Gas Pressure Regulator
S Safety Shutoff Valve
D
E