Carrier 48SS Options and accessories, Field-installed accessories, Unit with Optional Base Rail

Options and accessories

Factory-installed options

Unit with base rail provides holes for rigging and forklifts as well as an elevated mounting frame that gives additional structural support for horizontal installations. Ideal for light commercial applications.

Down¯ow option unit is shipped from factory con®gured for vertical ductwork connection. Unit is equipped with base rail.

Field-installed accessories

Factory-assembled roof curbs are designed for use on down¯ow discharge applications. Heavy gage, galvanized steel construction provides one-piece support. The curb com- plies with the standards of the NRCA (National Roo®ng Contractors Association). A wood nailing strip is provided for attaching the roo®ng to the curb.

25% Open manual outdoor-air damper provides for minimum outdoor air and is manually adjustable.

Thermostat and subbase provide heating and cooling unit control. The subbase provides system and fan switch- ing at the thermostat location.

Carrier electronic programmable thermostats pro- vide 2-stage heating and 2-stage cooling control with re- mote communication ability.

Low-ambient kit (Motormaster II device) allows the use of mechanical cooling down to outdoor ambient tem- peratures as low as 0° F.

LP conversion kit allows for conversion from natural gas to liquid propane. Conversion kit involves changing the gas ori®ces and adding ceramic baf¯es to accommodate liquid propane.

Solid-state Time Guard II device protects compressor by preventing short cycling.

Crankcase heater warms crankcase oil to reduce refrig- erant migration and ensure proper compressor lubrication. (Recommended on 208/230-v single-phase units in sizes 024-042 only).

UNIT WITH OPTIONAL BASE RAIL

High- and low-pressure switches provide additional safety features and protect the unit from running at unsuit- able pressures.

Filter rack features easy installation, serviceability, and high ®ltering performance for vertical applications.

Lifting bracket kit provides attachment points for rigging straps. The kit is not required when unit is equipped with an optional base rail or down¯ow application.

High altitude kit is for use at 2001 to 5000 feet above sea level. Kit consists of natural gas ori®ces that compen- sate for gas heat operation at high altitude.

Low NOx kit provides compliance with low NOx emissions requirements for units being installed in California Air Qual- ity Management Districts, which require NOx emissions of 40 nanograms/joule or less.

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