Section V Electrical Power, Manifold Pressures kpa

364861-UIM-B-0708

The furnace must be isolated from the gas supply piping system by closing its individual external manual shutoff valve during any pressure testing of the gas supply piping system at pressures equal to or less than 1/2 psig (3.5 kPa).

The gas valve body is a very thin casting that cannot take any external pressure. Never apply a pipe wrench to the body of the gas valve when installing piping. A wrench must be placed on the octa- gon hub located on the gas inlet side of the valve. Placing a wrench to the body of the gas valve will damage the valve causing improper operation and/or the valve to leak.

Gas piping may be connected from either side of the furnace using any of the gas pipe entry knockouts on both sides of the furnace. Refer to Figure 12, "Dimensions".

GAS ORIFICE CONVERSION FOR PROPANE (LP)

This furnace is constructed at the factory for natural gas-fired operation, but may be converted to operate on propane (LP) gas by using a fac- tory-supplied LP conversion kit. Follow the instructions supplied with the LP kit.

HIGH ALTITUDE GAS ORIFICE CONVERSION

This furnace is constructed at the factory for natural gas-fired operation at 0 –5,000 feet (0-m – 1,524 m) above sea level.

The manifold pressure must be changed in order to maintain proper and safe operation when the furnace is installed in a location where the altitude is greater than 5,000 feet (1,524 m) above sea level. Refer to Table 5, "Nominal Manifold Pressure - High Fire" for proper manifold pressure settings.

HIGH ALTITUDE PRESSURE SWITCH CONVERSION

For installation where the altitude is less than 5,000 feet (1,524m), it is not required that the pressure switch be changed unless you are in an area subject to low pressure inversions.

Table 5: Nominal Manifold Pressure - High Fire

Manifold Pressures (in wc)

				Altitude (feet)
			0-7999	8000-8999	9000-9999
		800	3.5	3.5	3.5

Value		850	3.5	3.5	3.5
Value	ft.)
		900	3.5	3.5	3.5
HeatingGas
	(BTU/cu	950	3.5	3.5	3.3

		1100	3.2	2.7	2.4
		1000	3.5	3.2	2.9
		1050	3.5	2.9	2.7

		2500 (LP)	9.8	8.2	7.5

Manifold Pressures (kpa)

				Altitude (m)
			0-2437	2438-2742	2743-3048
		29.8	0.87	0.87	0.87

HeatingValue		31.7	0.87	0.87	0.87
	(MJ/cum)	33.5	0.87	0.87	0.87
		35.4	0.87	0.87	0.81

		37.3	0.87	0.80	0.73
Gas		39.1	0.87	0.73	0.67
Gas		41.0	0.80	0.66	0.61

		93.2 (LP)	2.44	2.03	1.86

PROPANE AND HIGH ALTITUDE CONVERSION KITS

It is very important to choose the correct kit and/or gas orifices for the altitude and the type of gas for which the furnace is being installed.

Only use natural gas in furnaces designed for natural gas. Only use propane (LP) gas for furnaces that have been properly converted to use pro- pane (LP) gas. Do not use this furnace with butane gas.

Incorrect gas orifices or a furnace that has been improperly converted will create an extremely dangerous condition resulting in premature heat exchanger failure, excessive sooting, high levels of carbon monoxide, personal injury, property damage, a fire hazard and/or death.

High altitude and propane (LP) conversions are required in order for the appliance to satisfactory meet the application. An authorized distributor or dealer must make all gas conversions.

In Canada, a certified conversion station or other qualified agency, using factory specified and/or approved parts, must perform the conversion. The installer must take every precaution to insure that the furnace has been converted to the proper gas orifice size when the furnace is installed. Do not attempt to drill out any orifices to obtain the proper orifice size. Drilling out a gas orifice will cause misalignment of the burner flames, causing premature heat exchanger burnout, high levels of carbon monoxide, excessive sooting, a fire hazard, personal injury, property damage and/or death.