Wayne P250 series, User Manual

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When converting oil fired appliances, the flue pipe and draft hood or diverter used should be the same size as the furnace flue
collar. It is recommended that a rise as great as possible or at least 1/4 inch (6.35mm) to the foot (0.305m) (horizontal length)
be maintained in the flue pipe from the appliance to the chimney. The flue pipe should be relocated where possible to avoid
sharp turns.
DRAFT – When installing Wayne power gas burners in oil fired boilers a minimum negative draft of .02” (5 Pa) w.c. over fire
must be maintained. Refer to your local gas company and codes for assistance.
For gas fired equipment requiring a double acting barometric the preferred location of the barometric draft control is part o f the
bullhead tee shown in Figure 4. During normal operation, flue gases make a right angle turn behind the control, but do not
infringe upon it. Should a downdraft occur, air flowing in the opposite direction strikes the control directly, causing it to open
outwardly and vents the air into the room with a minimum of resistance. Entrained products of combustion are thus provided
greater relief.
FIGURE 4: BEST LOCATIONS FOR BAROMETRIC DRAFT CONTROL
DRAFT HOOD & FLUE PIPE SIZES FOR GAS CONVERSION
BURNERS IN FURNACES AND BOILERS
Not more than 6,500 Btu/hr (1.905 Kw) per square inch (645.2 mm
2
) of the flue area
Input – Btu/hr (Kw)
Draft Hood and
Flue Pipe Size
Up to --- 120,000 (35)
120,000 (35.17) --- 180,000 (53)
180,000 (52.75) --- 250,000 (73)
5 inch (127 mm)
6 inch (152 mm)
7 inch (178 mm)

NOTE: If the flue pipe exceeds 10 ft. (3.048m) in length, or contains more than two elbows, use next size larger pipe and draft
hood.

NOTE: All installations must operate with negative draft overfire. Refer to your local gas company and codes for assistance.
When installing the burner in revertible flue (down draft or diving flue type) furnaces or boilers, the draft hood (or draft diverter)
should be located at least one foot higher than the top of the highest point of the appliance flue passage or combustion cham ber. It
is also recommended that a vent pipe, not less than one inch in diameter, be provided from the highest point in the flue passage,
directly to the flue pipe. This is not necessary on the appliances with built in up draft bypass. The gas company serving the area
should be consulted in regards to their recommendations for converting this type of furnace or boiler.
The flue pipe should be securely supported and the joints fastened with sheet metal screws or riveted to prevent sagging, and in no
case should be located in a manner that will present a hazard to combustible building material. (Refer to local building code.)
Boiler/Furnace
Products of
Combustion
Products of
Combustion
Boiler/Furnace
Products of
Combustion
Barometric
Barometric
Barometric
Boiler/Furnace