Field Controls 46381400, CAS-2B-90E Furnace Boot User Manual

COMBUSTION AIR SYSTEM

Model: CAS-2B-90E Furnace Boot™

FURNACE
BOOT™

4” VRV

4” IAH
HOOD

This product is designed for use on the Beckett AFG burners,
for the purpose of routing combustion air directly to the
burner, with the added safety feature of the vacuum relief
valve.

NOTE: For burner inputs up to 1.5 gph at 100 psi input
pressure or equivalent.

“The Furnace Boot™ model CAS-2B-90E is for use only on
the designated burner(s) as described in these instructions
only when the specific burner includes this Furnace Boot™
when shipped from the burner manufacturer or where the
burner instructions specifically reference the model CAS-2B­90E Furnace Boot™ as an optional air intake system.”

ITEMS INCLUDED IN KIT:

1 - 90E Furnace Boot™
1 - Set of Gaskets
1 - 4” VRV
1 - 4” IAH Hood
1 - Burner Coupling Set

INSTALLER SUPPLIED ITEMS:

Duct Piping and Elbows
90° Elbows;
¼ “ NPT Female x ¼” NPT Male for
routing oil line

2 - Mounting Bolts

THE PURPOSE OF THE VACUUM
RELIEF VALVE (VRV)

The Vacuum Relief Valve is a safety
device to guard against combustion
problems associated with directly
connecting oil burners to the outside.
Typical problems can be caused by
blockage of the intake termination, icing
up of the ductwork and effects of leeward
side wind effects on a building.

VRV OPERATION

The VRV gate operates on changes in the
vacuum pressure generated by the inlet to
the oil burner. The VRV gate will remain
closed during normal burner operation.
During an abnormal operation (i.e., blockage of the intake or
change in external building pressures) an increased negative
pressure on the intake of the burner causes a reduction in
burner airflow. Under this condition, the VRV gate opens,
stabilizing and maintaining proper airflow to the burner. The
VRV gate closes again once the abnormal condition is
corrected.

Figure 1

INSTALLATION

1. Before the Furnace Boot™ can be mounted, a rectangular
hole (2 ½” X 6”) must be located and cut into the side of the
furnace cabinet. The hole is located from the center of the
burner intake. (See Figure 1)

2. Remove the oil pump and air bands from the burner
housing! Install the sealing gaskets onto the burner
housing. (See Figure 2) Replace existing pump coupling
with the coupling supplied with the Furnace Boot™.
Position the Furnace Boot™ over intake on the burner
housing. Align the holes in the Furnace Boot™ with the
holes in the housing and re-attach the oil pump. (See
Figure 3) Note: Replace pump coupling with the coupling
supplied with kit. The Furnace Boot™ extension is mounted
from the outside of the furnace cabinet and can be
mounted to allow the routing of the duct pipe from the
ceiling or from the floor. (See Figure 4) Assemble VRV
balance weight onto the gate. Screw the weight all the way
in. Then attach lock nut and knurl nut. (See Figure 4)

Figure 2

Figure 3

Figure 4

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