Raypak 992B manual Venting Installation Tips, Venting Configurations

5.Remove the screws, retaining ring and rain gasket from top of heater.

6.Remove the screws, flue collar and gasket from the run side of the tee located in the flue box on top of the heater.

7.Reverse the components and reattach in the new location.

8.Make sure that the stainless steel cover, now lo- cated on the run side of the tee, is sealed to avoid any flue gas spillage.

CAUTION: The silicone vent gaskets must be prop- erly reinstalled to prevent flue gas leakage. Replace any torn or worn vent gaskets.

The maximum and minimum venting length for Cate- gory I appliances shall be determined per the NFGC (U.S.) or B149 (Canada).

The diameter of vent flue pipe should be sized accord- ing to the NFGC (U.S.) and B149 (Canada). The minimum flue pipe diameter for conventional negative draft venting using double-wall Type B vent is: 10 in. for Model 992B; 12 in. for Models 1262B and 1532B; 14 in. for Models 2002B and 2072B; and 16 in. for 2342B.

NOTE: A vent adapter (field-supplied) must be used to connect Type B vent to the unit.

Venting Installation Tips

Support piping:

•horizontal runs - at least every 5 ft

•vertical runs - use braces

•under or near elbows

WARNING: Examine the venting system at least once a year. Check all joints and vent pipe connections for tightness, corrosion or deterioration.

Venting Configurations

For heaters connected to gas vents or chimneys, vent installations shall be in accordance with the NFGC (U.S.), or B149 (Canada), or applicable provisions of local building codes.

Natural Draft Vertical Venting (Category I)

Installation

Fig. 27: Natural Draft Vertical Venting

(Category I)

Natural draft venting uses the natural buoyancy of the heated flue products to create a thermal driving head that expels the exhaust gases from the flue. The nega- tive draft must be within the range of -.01 to -.08 in. WC as measured 12 in. above the appliance flue out- let to ensure proper operation. Vent material must be listed by a nationally recognized test agency.

The connection from the appliance vent to the stack must be as direct as possible and shall be the same di- ameter as, or larger than, the vent outlet. The horizontal breaching of a vent must have an upward slope of not less than 1/4 inch per linear foot from the heater to the vent terminal. The horizontal portions of the vent shall also be supported for the design and weight of the material employed to maintain clear- ances and to prevent physical damage or separation of joints.

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