GUIDE SPECIFICATIONS — 548F036-120 (cont)

548F

c. E-Coated copper-fin coils shall have a flexible epoxy polymer coating uniformly applied to all coil surface areas without material bridging between fins. Coating process shall ensure complete coil encapsulation. Color shall be high gloss black with gloss — 60 deg of 65 to 90% per ASTM D523-89. Uniform dry film thickness from 0.8 to

1.2 mil on all surface areas including fin edges. Superior hardness characteristics of 2H per ASTM D3363-92A and cross-hatch adhesion of 4B-5B per ASTM D3359-93. Impact resistance shall be up to 160 in./lb (ASTM D2794-93). Humidity and water immersion resistance shall be up to minimum 1000 and 250 hours respectively (ASTM D2247-92 and ASTM D870-92). Corro- sion durability shall be confirmed through testing to be no less than 1000 hours salt spray per ASTM B117-90. Coil construction shall be copper fins mechanically bonded to copper tubes with copper tube sheets. Galvanized steel tube sheets shall not be acceptable. A polymer strip shall pre- vent coil assembly from contacting sheet metal coil pan to maintain coating integrity and minimize corrosion potential between coil and pan.

d.Optional pre-coated aluminum-fin coils shall have a durable epoxy-phenolic coating to provide pro- tection in mildly corrosive coastal environments. 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. Epoxy-phenolic barrier shall minimize gal- vanic action between dissimilar metals.

F.Refrigerant Components: Refrigerant circuit components shall include:

1.Fixed orifice multiple independent circuit metering system.

2.Service gage connections on suction, discharge, and liquid line to charge, evacuate, and contain refrigerant.

3.Accumulator.

4.Reversing valve.

G.Filter Section:

1.Standard filter section shall consist of factory- installed low-velocity, throwaway 2-in. thick fiberglass filters of commercially available sizes.

2.Filter face velocity shall not exceed 300 fpm at nomi- nal airflows.

3.Filter section shall use only one size filter.

4.Filters shall be accessible through an access panel with ‘‘no-tool’’ removal.

H.Controls and Safeties:

1.Unit Controls:

a.Unit shall be complete with self-contained low- voltage control circuit.

b.Unit shall incorporate an outdoor coil defrost system to prevent excessive frost accumulation during heating duty, and shall be controlled as follows:

1)Defrost shall be initiated on the basis of time and coil temperature.

2)A 30/50/90-minute timer shall activate defrost cycle only if coil temperature is low enough to indicate a heavy frost condition.

3)Defrost cycle shall terminate when defrost thermostat is satisfied and shall have a positive termination time of 10 minutes.

c.Unit shall contain high-pressure, loss-of-charge/ low-pressure, and freeze protection switches. It shall mount on factory-installed Schrader fittings.

2.Standard Safeties:

Unit shall incorporate compressor overtemperature and overcurrent safety devices to shut off compressor.

I.Operating Characteristics:

1.Unit shall be capable of starting and running in cool- ing at 115 F ambient outdoor temperature, meeting maximum load criteria of ARI Standard 210/240 at ±10% voltage.

2.Compressor with standard controls shall be capable of cooling operation down to 25 F ambient outdoor temperature.

3.Compressor shall be capable of operation in heating duty down to –10 F ambient outdoor-air temperature.

4.Unit shall be capable of simultaneous heating duty and defrost cycle operation when using electric heat- ers indicated in Section L, Special Features.

J.Electrical Requirements:

All unit power wiring shall enter unit cabinet at a single factory-predrilled location.

K.Motors:

1.Compressor motors shall be cooled by refrigerant passing through motor windings and shall have line break thermal and current overload protection.

2.Indoor blower motor shall have permanently lubri- cated bearings and inherent automatic-reset thermal overload protection.

3.Totally enclosed outdoor-fan motor shall have permanently lubricated bearings, and inherent automatic-reset thermal overload protection.

L.Special Features:

Certain features are not applicable when the features designated by * are specified. For assistance in amend- ing the specifications, your local Bryant Sales Office should be contacted.

1.Roof Curbs:

a.Formed galvanized steel with wood nailer strip and capable of supporting entire unit weight.

b.Allows for installing and securing ductwork to curb prior to mounting unit on the curb.

*2. Integrated Economizers:

a.Integrated integral modulating type capable of simultaneous economizer and compressor opera- tion. During economizer operation, up to two compressors on sizes 090-120 will operate.

b.Available as a factory-installed option in vertical supply/return configuration only. (Available as a field-installed accessory for dedicated horizontal and/or vertical supply return configurations.)

c.Includes all hardware and controls to provide cooling with outdoor air.

d.Equipped with low-leakage dampers, not to exceed 2% leakage at 1 in. wg pressure differential.

e.Capable of introducing up to 100% outdoor air.

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Bryant 549C manual Guide Specifications 548F036-120