Carrier 48SS018-060, 48SX024-060 user manual Sediment Trap

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Unstable operation may occur when the gas valve and manifold assembly are forced out of position while connecting improperly-routed rigid gas piping to the gas valve. Use a backup wrench when making con- nection to avoid strain on, or distortion of, the gas control piping.

If a ¯exible conductor is required or allowed by the authority having jurisdiction, black iron pipe shall be installed at the gas valve and shall extend a mini- mum of 2 in. outside the unit casing.

Never use a match or other open ¯ame when check- ing for gas leaks. Never purge gas line into com- bustion chamber. Failure to follow this warning could result in an explosion causing personal injury or death.

8.Check for gas leaks at the ®eld-installed and factory- installed gas lines after all piping connections have been completed. Use soap-and-water solution (or method speci- ®ed by local codes and/or regulations).

Fig. 15 Ð Sediment Trap

Step 9 Ð Install Duct Connections Ð The unit has duct ¯anges on the supply- and return-air openings on the side and bottom of the unit. See Fig. 2-9 for connection sizes and locations.

CONFIGURING UNITS FOR DOWNFLOW (VERTICAL) DISCHARGE

Before performing service or maintenance operations on the system, turn off main power to unit or electrical shock could result.

1.Open all electrical disconnects before starting any serv- ice work.

2.Remove return duct cover located on duct panel. Figure 16 shows duct cover removed. Save duct cover and screws.

3.Locate lances in basepan insulation that are placed over the perimeter of the vertical duct opening cover (Fig. 17).

4.Using a straight edge and sharp knife, cut and remove the insulation around the perimeter of the cover. Re- move and save 5 screws securing the cover to the base- pan and slide out the cover. Discard the cover (Fig. 18).

5.Remove supply duct cover located on duct panel. Figure 16 shows duct cover removed. Save duct cover and screws.

6.Remove and discard 2 screws which secure vertical dis- charge opening cover to basepan (Fig. 19). Slide cover forward to disengage, then tilt and remove cover through vertical discharge opening in bottom of unit. Discard duct cover (Fig. 20).

Collect ALL screws that were removed. Do not leave screws on rooftop as permanent damage to the roof may occur.

7.If unit ductwork is to be attached to vertical opening ¯anges on the unit basepan (jackstand applications only), do so at this time.

8.It is recommended that the basepan insulation around the perimeter of the vertical return-air opening be se- cured to the basepan with aluminum tape. Applicable local codes may require aluminum tape to prevent ex- posed ®berglass.

9.Cover both horizontal duct openings with the duct cov- ers from Steps 2 and 5. Make sure opening is air- and watertight.

10.After completing unit conversion, perform all safety checks and power up unit.

NOTE: The design and installation of the duct system must be in accordance with the standards of the NFPA for instal- lation of nonresidence-type air conditioning and ventilating systems, NFPA 90A or residence-type, NFPA 90B; and/or local codes and residence-type, NFPA 90B; and/or local codes and ordinances.

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