Mounting
On vertical vents, the vent damper may be mounted with the actuator in any position. On horizontal vents, do not mount the actuator either directly above or directly below the vent pipe; mount the vent damper actuator to the side of the vent.
The vent damper is set up for a continuous pilot sys- tem. If the vent damper is installed on a system with an Intermittent Pilot, the energy savings of the vent damper can be improved by plugging the hole in the vent damper blade using the knockout plug provided in the parts envelope.
Hole in Vent Damper Blade Closed Position 
DO NOT plug the hole if installing the vent damper on a continuous pilot system as this will create a haz- ardous condition.Fig. 8: Vent Damper
Fig. 9: Installing The Vent Damper in Horizontal
& Vertical Vents
Fig. 10: D80D General Wiring Diagram
Install the vent damper to service only the single appliance for which it is intended. If improperly installed, a hazardous condition, such as an explo- sion or carbon monoxide poisoning, could result.
Vent Damper Operation
For safe, efficient operation, the vent damper and all
Check vent damper operation as follows:
1.When the boiler is off, check that the vent damper position indicator points to the closed position (see Fig. 11).
Damper Position Indicator
Damper OpenDamper Closed
Fig. 11: Vent Damper Position Indicator
12