14
The purpose of the damper is to act as a vacuum breaker in the event of a blockage in the air intake.
NOTE: The balance weight of the vacuum relief valve must be installed in a level position and adjusted to lightly close while burner is operating. Be sure to lock the balancing weight after adjustment.
ALL JOINTS IN THE AIR INTAKE ASSEMBLY MUST BE SECURELY FASTENED.
THE MAXIMUM LENGTH OF FLEXIBLE AIR INTAKE DUCT, WHICH CAN BE RUN TO THE BURNER, IS TWENTY FEET PLUS THE LENGTH THAT RESULTS FROM THE 4” TEE AND 4” ELBOW SUPPLIED.