INSTALLATION –
CAS-2B Field Control AIRBOOT™ Outside Combustion Air Kit
2
4
-530
Assembly/Installation
The recommended procedure for assembly and installation
is described as follows:
Step 1 - AIRBOOT™ Installation
A. Remove the fuel pump, air shutter, and air band from
the burner housing.
B. Remove the original shaft coupling (or inlet air shutoff if
applicable; the inlet air shutoff cannot be used with the
boot) and install the extended coupling, part #21775.
C. Install both sealing gaskets to burner housing, part
#31989. (Figure 1, Page 1).
D. Position the AIRBOOT™ over the burner housing on the
air intake side.
E. Align the holes in the AIRBOOT™ with the holes in the
housing. Guide the pump shaft into the extended
coupling and secure the fuel pump with the 1/4-20 x 1-
1/4 mounting screws (do NOT over tighten pump bolts)
NOTE: The AIRBOOT™ may be oriented either vertically or
horizontally as space allows (Figure 2). The round spacer
ring attached to the AIRBOOT™ can be detached by
removing the two (2) plastic fasteners, rotating the spacer
plate 90° (from vertical mounting), and reinstalling the plastic
fasteners. (Figure 3, Page 2)
NOTE: If the fuel lines have been disconnected in order to
remove the fuel unit, or if this is a new installation, the fuel
unit may require bleeding before initial burner start-up (look
under Burner Start-Up and Adjustment for bleeding
procedures).
Step 2. Assembly/Installation of the VRV
Purpose of the Vacuum Relief Valve (VRV)
The VRV is installed to provide a secondary opening for
combustion air supply in the duct system. This is especially
important in the event of damage or blockage to the Intake
Air Hood.
VRV Operation
The VRV gate operates on changes in vacuum pressure
generated between the intake and the oil burner. The VRV
gate will remain closed during normal burner operation.
During any abnormal operation created by blockage of the
Intake Air Hood, duct pipe, or significant changes in external
building pressures, an increased negative pressure on the
intake of the burner causes a reduction in burner air flow.
Under this condition, the VRV gate opens, stabilizing and
maintaining proper air flow to the burner. The VRV gate
closes again once the abnormal condition is corrected.
A. Mount VRV tee assembly or 90° elbow into the
AIRBOOT™ intake. Fasten using three (3) sheet metal
screws on all joints (Figure 4).
OUTSIDE
WALL
INTAKE AIR
HOOD
INSTALLER
SUPPLIED
4” PIPE
ALTERNATE
VRV
LOCATION
VRV
LOCATION
AIRBOOT
™
FIGURE 4
SK9554
B. Assemble VRV balance weight onto gate. Screw the
weight all the way in, and then attach lock nut and
knurled nut (Figure 5).
BALANCE
WEIGHT
GATE
LOCK
NUT
KNURLED
NUT
VRV
ASSEMBLY
FIGURE 5
SK9556
C. Mount the VRV assembly into the tee and fasten with
screw and nut in collar tabs. To ensure proper
operation, check the gate for being plumb as well as
being level across the pivot point (Figure 6).
Vertical Orientation
Horizontal Orientation
FIGURE 2
SK9553
SPACER
RING
PLASTIC
FASTENERS
FIGURE 3
SK9552