Bryant 548J manual 23 81 19.13.K. Refrigerant Components

548J

2.Optional Pre-coated aluminum-fin condenser coils: on all models.

a.Shall have a durable epoxy-phenolic coating to provide protection in mildly corrosive coastal environments.

b.Coating shall be applied to the aluminum fin stock prior to the fin stamping process to create an inert barrier between the aluminum fin and copper tube.

c.Epoxy-phenolic barrier shall minimize galvanic action between dissimilar metals.

3.Optional Copper-fin evaporator and condenser coils: on all models.

a.Shall be constructed of copper fins mechanically bonded to copper tubes and copper tube sheets.

b.Galvanized steel tube sheets shall not be acceptable.

c.A polymer strip shall prevent coil assembly from contacting the sheet metal coil pan to minimize potential for galvanic corrosion between coil and pan.

4.Optional E-coated aluminum-fin evaporator and condenser coils: on all models.

a.Shall have a flexible epoxy polymer coating uniformly applied to all coil surface areas without material bridging between fins.

b.Coating process shall ensure complete coil encapsulation of tubes, fins and headers.

c.Color shall be high gloss black with gloss per ASTM D523-89.

d.Uniform dry film thickness from 0.8 to 1.2 mil on all surface areas including fin edges.

e.Superior hardness characteristics of 2H per ASTM D3363-92A and cross-hatch adhesion of 4B-5B per ASTM D3359-93.

f.Impact resistance shall be up to 160 in.-lb (ASTM D2794-93).

g.Humidity and water immersion resistance shall be up to minimum 1000 and 250 hours respectively (ASTM D2247-92 and ASTM D870-92).

h.Corrosion durability shall be confirmed through testing to be no less than 1000 hours salt spray per ASTM B117-90.

23 81 19.13.K. Refrigerant Components

1.Refrigerant circuit shall include the following control, safety, and maintenance features:

a.Fixed orifice metering system shall prevent mal-distribution of two-phase refrigerant by including multiple fixed orifice devices in each refrigeration circuit. Each orifice is to be optimized to the coil circuit it serves.

b.Refrigerant filter drier.

c.Service gauge connections on suction and discharge lines.

d.Pressure gauge access through a specially designed access port in the top panel of the unit.

e.Suction line accumulator to provide protection in all operating modes from cooling, heating and reverse cycle switching.

2.There shall be gauge line access port in the top of the rooftop, covered by a black, removable plug.

a.The plug shall be easy to remove and replace.

b.When the plug is removed, the gauge access port shall enable maintenance personnel to route their pressure gauge lines.

c.This gauge access port shall facilitate correct and accurate condenser pressure readings by enabling the read- ing with the compressor access panel on.

d.The plug shall be made of a leak proof, UV-resistant, composite material.

3.Compressors

a.Unit shall use one fully hermetic, scroll compressor for each independent refrigeration circuit.

b.Models shall be available with single compressor designs on 04-12 models, plus additional 2 compressor (stage) models from 08-09 sizes.

c.Compressor motors shall be cooled by refrigerant gas passing through motor windings.

d.Compressors shall be internally protected from high discharge temperature conditions.

e.Compressors shall be protected from an over-temperature and over-amperage conditions by an internal, motor overload device.

f.Compressor shall be factory mounted on rubber grommets.

g.Compressor motors shall have internal line break thermal, current overload and high pressure differential pro- tection.

h.Crankcase heaters shall be utilized on all models (except 04 size) to protect compressor with specific refriger- ant charge.

23 81 19.13.L. Filter Section

1.Filters access is specified in the unit cabinet section of this specification.

2.Filters shall be held in place by a pivoting filter tray, facilitating easy removal and installation.

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