GSW G65 Venting, DIA Area, Sq, Input Natural GAS Propane BTU/HR, 1000 BTU/CU. FT 2500 BTU/CU. FT

Table II

No. of seconds required to consume 1 cu. ft. of gas.
INPUT	NATURAL GAS	PROPANE
BTU/HR.	1000 BTU/CU. FT.	2500 BTU/CU. FT.
58,000	62 SEC.	155 SEC.
90,000	40 SEC.	100 SEC.
135,000	27 SEC.	67 SEC.
160,000	22 SEC.	56 SEC.
180,000	20 SEC.	50 SEC.
200,000	18 SEC.	45 SEC.
225,000	16 SEC.	40 SEC.
270,000	13 SEC.	33 SEC.
315,000	12 SEC.	29 SEC.
360,000	10 SEC.	25 SEC.

VENTING

To carry off the products of combustion, a vent pipe must be attached to the drafthood of the heater and connected to a chimney vent of adequate height and area. Venting connections should be made in accordance with all codes and ordinances which apply.

Ensure that the vent pipe is securely fastened to the draft hood and that the draft hood is properly attached to the heater. For a single heater installation the vent pipe must be sized no small- er than the flue size of the heater. Horizontal runs of vent pipe should be installed with a rise of at least 1/4” per foot of length. The vertical connector rise of vent pipe above the draft hood, before any fittings, should be as great as possible.

When more then one heater is installed and the vents are combined, the area of the horizontal manifold and common vent should be at least equal to the area of the largest single vent, plus 50% of the area of all other vents joining it (see Vent Size Chart below) (For example, to combine two 6” vents with a 5” vent, the area of the combined vent would be equal to 28 + 28/2+20/2 equals 52 square inches - use a minimum 9 inch common vent and manifold). Units with larger inputs must be vented below others. When using a common vent connector, it shall be at the highest practical level.

VENT TOP

OR CAP

COMMON

CHIMNEY VENT

MANIFOLD

VENT CONNECTOR

TEE

CONNECTORCAPPED RISE

The chimney vent must be extended at least two feet higher than any obstruction located within 10 feet.

Where a back draft exists, the cause must be determined and corrected. A flue cap on the chimney vent may correct the sit- uation. However, if the back draft cannot be corrected, if long horizontal vent pipe runs are necessary, or if a suitable flue cannot be obtained, a mechanical exhaust may be required to ensure proper venting and combustion.

DIA.	AREA	DIA.	AREA		Some local codes prohibit connecting a gas heater to a flue or
IN.	SQ. IN.	IN.	SQ. IN.		chimney with coal or oil fired equipment. Therefore, these
					connections should be avoided. However, where a separate
5	20	10	79		chimney is not available, the flue pipe from the water heater
					should enter the common flue or chimney at a point ABOVE
6	28	12	113		the flue pipe from the coal or oil fired equipment.
7	38	14	154		Improper venting may result in poor combustion, sooting and
8	50	16	201
					serious damage to the heater.
9	64
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