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GUIDE SPECIFICATIONS — 580F036-151 AND 581B036-150 (cont)
2. Dual compressor models (size 090-150) shall have
face-split type evaporator coil (circuit no. 1 on
bottom).
3. Testing:
a. Evaporator and condenser coils shall be qualified
to UL 1995 burst test at 2,200 psi.
b. Evaporator and condenser coils shall be leak
tested to 150 psig and pressure tested to
400 psig.
4. Optional Coils:
a. Optional pre-coated a luminu m-fin coils shal l ha ve
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.
b. Copper-fin coils shall be constructed of copper
fins mechanically bonded to copper tubes and
copper tube sheets. Galvanized steel tube sheets
shall not be acceptable. A polymer strip shall pre-
vent coil assembly from contacting the sheet
metal coil pan to minimize potential for galvanic
corrosion between coil and pan. All copper con-
struction shall provide protection in moderate
coastal environments.
c. E-Coated aluminum-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 alumi-
num fins mechanically bonded to copper tubes.
d. 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.
F. Heating Section:
1. Induced-draft combustion type with energ y saving
direct-spark ignition system and redundant main gas
valve.
2. Heat Exchanger:
a. The standard heat exchanger shall be of the
tubular-section type constructed of a minimum of
20-gage steel coated with a nominal 1.2 mil
aluminum-silicone alloy for corrosion resistance.
b. The optional stainless steel heat exchanger shall
be of the tubular-section type, constructed of a
minimum of 20-gage type 409 stainless steel.
3. Burners shall be of the in-shot type constructed of
aluminum-coated steel.
4. All gas piping shall enter the unit cabinet at a single
location on side of unit (horizontal plane).
5. The integrated gas controller (IGC) board shall
include gas heat operation fault notification using an
LED (light-emitting diode).
6. Unit shall be equipped with anti-cycle protection with
one short cycle on unit flame rollout switch or 4 con-
tinuous short cycles on the high-temperature limit
switch. Fault indication shall be made using an LED.
7. The IGC board shall contain algorithms that modify
evaporator-fan operation to prevent future cycling on
high-temperature limit switch.
8. The LED shall be visible without removal of control
box access panel.
G. Refrigerant Components:
Refrigerant circuit components shall include:
1. Fixed orifice metering system.
2. Refrigerant filter drier.
3. Service gage connections on suction, discharge, and
liquid lines.
H. 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 320 fpm at nomi-
nal airflows.
3. Filter section should use only one size filter.
4. Filters shall be accessible through an access panel
with “no-tool” removal.
I. Controls and Safeties:
1. Unit Controls:
Unit shall be complete with self-contained low-volt-
age control circuit protected by a fuse on the 24-v
transformer side (090-150 units have a resettable
circuit breaker).
2. Safeties:
a. Unit shall incorporate a solid-state compressor
protector which provides anti-cycle reset capabil-
ity at the space thermostat, should any of the fol-
lowing standard safety devices trip and shut off
compressor.
1) Compressor overtemperature, overcurrent.
2) Loss-of-charge/low-pressure switch.
3) Freeze-protection thermostat, evaporator coil.
4) High-pressure switch.
5) Automatic reset motor thermal overload
protector.
581B036-150