36
1.
Verify only boiler is serviced by Vent Damper. Figure 2.
2.
Clearance of 6 inches (152 mm) between Vent
Damper and combustible material shall be maintained.
Allow additional clearance for service of Vent Damper.
3.
Vent Damper shall be in the open position when
appliance main burners are operating.
4.
Vent Damper position indicator must be in visible
location following installation.
APPENDIX B - VENT DAMPER INSTALLATION
B.1
Damper Installation
Follow Damper installation instructions provided with
damper. See Figure 1a & 1b
.
Figure 1a - Horizontal Installations
Figure 2 - Alternate Vent Damper Installation
Check vent damper and all flue product carrying areas of
boiler annually for deterioration from corrosion or other
sources. Contact your service agent for repairs.
Check Vent Damper Operation as follows:
1.
When boiler is off, check vent damper position
indicator points to closed position. See Figure 3.
2.
Turn thermostat or controller up to call for heat and
check vent damper indicator points to open position
See Figure 3.
3.
Turn thermostat or controller down again and check
damper position indicator returns to closed position.
4.
Return thermostat to desired position.
5.
Place vent damper in open position to permit burner
operation by using “HOLD DAMPER OPEN” switch,
located on damper controller.
6.
Thermostat controls burner firing as before, while
damper remains open.
7.
DO NOT turn damper open manually, motor damage
will result.
8.
Set switch to “AUTOMATIC OPERATION” to close vent
damper during burner off cycle.
9.
For further information, and for vent damper
troubleshooting guide, refer to manual packaged with
vent damper.
Flue Gas
Flue Gas
Flow
OPEN
CL
OSED
RO
TA
TION
CL
OSED
OPEN
RO
TA
TION
Damper Closed
Damper Open
Open and Closed Positions Shown
B.2 Vent Damper
WARNING
Asphyxiation, burn hazard. Improper operation of
vent damper may result in serious injury or death
due to fire or to asphyxiation from poisonous gases
such as carbon monoxide which is odorless and
invisible.
!
Figure 3 - Vent Damper Position Indicator
Do Not
Install Here
Do not install Vent
Damper within
6" (152mm) of
combustible material
Install Damper Here
Water
Heater
Chimney
Boiler
To Boiler
Vent Damper
T
o Chimney
NO
NO
YES
YES
Flow
Install vent damper with actuator to sides of
vent only. Do not mount above or below vent
T
o Chimney
Vent
Damper
To Boiler
Actuator may be
installed in any
position
Flow
Figure B-1b - Vertical Installations
PN 240012785 Rev. C [11/15/2020]
