York D7CG 060, D7CG 036 External Supply Connection, Bottom Supply Connection, External Shut-Off

530.18-N8Y

FIG. 3 - EXTERNAL SUPPLY CONNECTION	FIG. 4 - BOTTOM SUPPLY CONNECTION
EXTERNAL SHUT-OFF	EXTERNAL SHUT-OFF

The heating value of the gas may differ with locality. The value should be checked with the local gas utility.

NOTE: There may be a local gas utility requirement specifying a minimum diameter for gas piping. All units require a 1/2 inch pipe connection at the entrance fitting.

GAS CONNECTION

The gas supply line can be routed through the knockouts located on the front of the unit or through the opening provided in the unit’s base. Refer to Figure 9 to locate these access openings. Typical supply piping arrangements are shown in Figures 3 and 4. All shaded items are field-supplied.

Two grommets are shipped in the blower compartment (in parts bag taped to the blower housing) of every unit with gas heat and should be used in the knockouts when the gas piping penetrates the front of the unit.

After the gas supply piping has been installed, the bottom opening should be sealed to prevent water from leaking into the building.

Gas piping recommendations:

1.A drip leg and a ground joint union must be installed in the gas piping.

2.When required by local codes, a manual shut-off valve may have to be installed outside of the unit.

3.Use wrought iron or steel pipe for all gas lines. Pipe compound should be applied sparingly to male threads only.

WARNING: Natural gas may contain some propane. Propane, being an excellent solvent, will quickly dissolve white lead or most standard commercial com- pounds. Therefore, a special pipe compound must be applied when wrought iron or steel pipe is used. Shellac base compounds such as Gaskolac or Stalastic, and compounds such as Rectorseal #5, Cyde’s or John Crane may be used.

4.All piping should be cleaned of dirt and scale by hammering on the outside of the pipe and blowing out the loose dirt and scale. Before initial start-up, be sure that all of the gas lines external to the unit have been purged of air.

5.The gas supply should be a separate line and installed in accordance with all safety codes as prescribed under “Limitations”. After the gas connections have been completed, open the main shut-off valve admitting normal gas pressure to the mains. Check all joints for leaks with soap solution or other material suitable for the purpose.

NEVER USE A FLAME.

6.The furnace and its individual manual shut-off valve must be disconnected from the gas supply piping system during any pressure testing of that system at test pressures in excess of 1/2 psig (3.48kPa).

The furnace must be isolated from the gas supply piping system by closing its individual manual shut-off valve during any pressure testing of the gas supply piping system at test pressures equal to or less than 1/2 psig (3.48kPa).

7.A 1/8 inch NPT plugged tapping, accessible for test gage connection, must be installed immediately upstream of the gas supply connection to the furnace.

L.P./PROPANE UNITS, TANKS AND PIPING

All gas heat units are shipped from the factory equipped for natural gas use only. The unit may be converted in the field for use with L.P./propane gas with accessory kit model number 1NP0440.

All L.P./propane gas equipment must conform to the safety standards of the National Fire Protection Association.

For satisfactory operation, L.P./propane gas pressure must be

10.5inch W.C at the unit under full load. Maintaining proper gas pressure depends on three main factors:

1.The vaporization rate which depends on (a) the temperature of the liquid and (b) the “wetted surface” area of the container or containers.

2.The proper pressure regulation. (Two-stage regulation is recommended from the standpoint of both cost and efficiency.)

3.The pressure drop in the lines between regulators and between the second stage regulator and the appliance. Pipe size required will depend on the length of the pipe run and the total load of all appliances.

Complete information regarding tank sizing for vaporization, recommended regulator settings, and pipe sizing is available from most regulator manufacturers and L.P./propane gas suppliers.

L.P./propane gas is an excellent solvent and special pipe compound must be used when assembling piping for this gas as it will quickly dissolve white lead or most standard commercial compounds. Shellac base compounds such as Rectorseal #5 are satisfactory for this type of gas.

Check all connections for leaks when piping is completed, using a soap solution. NEVER USE A FLAME.

LOW NOx APPLICATION

For natural gas heat installations in locations which require low Nitros Oxide emissions, accessory model 1LN0404 must be installed.

6 Unitary Products Group