Carrier 39CCN Installation, Start-up And Service Instructions Manual

45. Roof the curb prior to setting the unit. Use standard 2 in. x4 in. wood nailers (provided), insulate and flash (by oth-ers) as required.6. Check to ensure that curb is level and securely attached tostructure.7. Check for sufficient height between the unit base and theroof to allow for drain trapping.8. Use polyurethane caulking on top of the curb to seal be-tween the unit base and the roof curb.9. Safely lift the unit into place.The installer is responsible for installing roof curb in accor-dance with local building and earthquake codes.Duct/Weather Hood Installation — FollowSMACNA and industry guidelines for duct gages, sizing, ma-terials, insulation and supports. Transition to and from units asrequired for proper airflow. When installing ductwork orweather hoods to unit exterior, use gaskets or caulking aroundentire perimeter of flange. Align the duct or hood over theopening. Check for adequate clearance to doors and otheropenings. Install the duct of hood using sheet metal screwsthrough the unit casing. Carefully remove excess caulking, ifrequired, from around the flange.Electrical Connections — Follow the latest NEC (Na-tional Electrical Code) and/or other applicable codes for allelectrical wiring and connections, including grounding.Nameplate data contains line voltage and minimum ampac-ity for this unit. Separate line voltage power supply should berun directly from the building distribution panel to the electri-cal connection on the unit. Consult wiring diagrams providedwith the unit. Follow NEC and applicable codes for conduitand wire ratings.CoilsHEATING COILS (HOT WATER, STEAM) — Heatingcoils are constructed of copper tube with corrugated fins. Max-imum operating pressure is 150 psig. Coils are provided withdrain and vent connections. Do not block the air vent; this mayresult in poor coil performance. Inlet line strainers are recom-mended to prevent debris from blocking coil tubes or valves.Common causes of heating coil damage are:• improper piping installation• water hammer• freezing• control valve chattering• internal corrosion from chemicals in fluid• external corrosion from chemicals in the airstreamCOOLING COILS (CHILLED WATER, DIRECT EXPAN-SION, GLYCOL) — Cooling coils are constructed of coppertube with corrugated fins. Maximum operating pressure is150 psig. An IAQ 304SS (indoor air quality 304 stainless steel)condensate drain pan is located under the coil with drain andvent connections. Do not block the air vent; this may result inpoor coil performance. Inlet line strainers are recommended toprevent debris from blocking coil tubes or valves.Common causes of water cooling coil damage are:• improper piping installation• water hammer• freezing• control valve chattering• internal corrosion from chemicals in fluid• external corrosion from chemicals in the air streamDirect expansion (DX) cooling coils are thermal counter-flow construction with same end liquid and suctionconnections.Common causes of DX cooling coil damage are:• improper piping installation• freezing (due to excessively low pressure)• internal corrosion• external corrosion from chemicals in the air streamRefrigerant distributors are brass, pressure type with copperdistributor tubes factory installed.Reassembly of Split Units — To prevent air and wa-ter leaks, all units shipped in sections must be carefully assem-bled and installed on a proper foundation. Split air units are as-sembled in one piece in the factory to make sure that all piecesmatch and the bolt holes line up, and are then split prior to ship-ping.• For proper reassembly, housekeeping pad or roof curbmust be level.• All nuts, bolts, washers, and caulking required forassembly of the unit are shipped in the supply fan sec-tion.• Place all sections on level surface.• Caulk where indicated on both sides of split panel androof flanges, and bolt the base together. See Fig. 6.• A come-along or hand-operated winch can be used totighten the space between unit section.• Bolt holes may not align as a result of racking duringtransit to the job site. In such instances, lift one side withjack to align holes on wall of the opposite side. Afterbolting this wall, remove jack. Then proceed with boltingthe other side, base, floor, and roof. Any racking that isout of square should realign as the unit settles.• Check to make sure that all bolts are properly secured.• Caulk exterior roof seams. See Fig. 7.CAULKINGa39-4465Fig. 6 — Caulking Split Panel Flanges