Hayward 350K Negative Pressure Indoor Vent Adapter | UHXNEGVT13508

The heater is designed such that it may be vented using either a negative-pressure or a positive-pressure venting system. The appropriate system of venting for a particular site will depend on many factors such as vent termination needs (horizontal/vertical), and the cost of venting system. Table 2 lists the indoor venting kits available and the limitations of each system. Heaters come stock with outdoor top. These tops are 8" in diameter (Negative or Positive) for all indoor venting applications.