Product data

82
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 respec-
tively (ASTM D2247-92 and ASTM D870-
92). Corrosion durability shall be confirmed
through testing to be no less than 1000
hours salt spray per ASTM B117-90. Coil
construction shall be aluminum fins mechan-
ically bonded to copper tubes.
c. E-Coated copper-fin coils shall have a flexi-
ble 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 resis-
tance 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). Corrosion 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 poly-
mer strip shall prevent coil assembly from
contacting sheet metal coil pan to maintain
coating integrity and minimize corrosion
potential between coil and pan.
d. Optional precoated aluminum-fin coils shall
have a duable epoxy-phenolic coating to
provide protection 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 compo-
nents shall include:
1. Acutrol™ 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
fiber-glass filters of commercially available sizes.
2. Filter face velocity shall not exceed 300 fpm at
nominal 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 overtemper-
ature and overcurrent safety devices to shut off
compressor.
I. Operating Characteristics:
1. Unit shall be capable of starting and running in
cooling at 125 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 heaters indicated in Section L, Special
Features.
J. Electrical Requirements:
All unit power wiring shall enter unit cabinet at a sin-
gle factory-predrilled location.
Guide specifications — 50TFQ units (cont)
50TFQ004-01250TFQ004-012