Carrier WEATHERMASTER 50HJQ004-016 Product Data page 156

Guide specifications — 50HJQ014,016 (cont)
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-
voltage control circuit protected by a resettable
circuit breaker on the 24-v transformer side.
2. Safeties:
a. Unit shall incorporate a solid-state compres-
sor protector which provides anti-cycle reset
capability at the space thermostat, should
any of the following standard safety devices
trip and shut off compressor.
1) Compressor overtemperature, overcur-
rent.
2) Loss-of-charge/low-pressure switch.
3) Freeze-protection thermostat, evapora-
tor coil.
4) High-pressure switch.
5) Automatic reset motor thermal overload
protector.
The lockout protection shall be easily discon-
nected at the control board, if necessary.
b. Heating section shall be provided with the
following minimum protections:
1) High-temperature limit switches.
2) Overcurrent protection.
c. 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 the coil temperature
is low enough to indicate a heavy frost
condition.
3) Defrost cycle shall terminate when
defrost thermostats are satisfied and
shall have a positive termination time of
10 minutes.
J. Operating Characteristics:
1. Unit shall be capable of starting and running
at 125 F ambient outdoor temperature, meet-
ing maximum load criteria of ARI Standard
210/240 or 360 at + 10% voltage.
2. Compressor with standard controls shall be
capable of operation down to 40 F (in cooling
mode) ambient outdoor temperature.
3. Compressor with standard controls shall be
capable of operation down to –20 F (in heating
mode) ambient outdoor temperature.
4. Unit shall be capable of simultaneous heating
duty and defrost cycle operation when using
accessory electric heaters.
156
K. Electrical Requirements:
All unit power wiring shall enter unit cabinet at a
single factory-predrilled location.
L. Motors:
1. Compressor motors shall be cooled by refriger-
ant gas passing through motor windings and
shall have line break thermal and current over-
load protection.
2. Indoor-fan 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.
M. Special Features:
Certain features are not applicable when the fea-
tures designated * are specified. For assistance in
amending the specifications, contact your local
Carrier Sales Office.
* 1. Carrier PremierLink™ Controls:
a. Shall be available as a factory-installed or as
a field-installed accessory.
b. Shall work with CCN and ComfortVIEW™
software.
c. Shall be compatible with ComfortLink™
controllers.
d. Shall be ASHRAE 62-2001 compliant.
e. Shall accept a CO
space — Demand Control Ventilation (DCV)
Ready.
f. Shall have baud communication rate of
38.4K or faster.
g. Shall be Internet Ready.
h. Shall include an integrated economizer
controller.
2. Roof Curbs (Horizontal and Vertical):
a. Formed galvanized steel with wood nailer
strip and shall be capable of supporting
entire unit weight.
b. Permits installation and securing of ductwork
to curb prior to mounting unit on the curb.
3. Horizontal Adapter Roof Curb:
Includes factory-assembled adapter and duct.
NOTE: Power exhaust and barometric relief
must be mounted in the return ductwork when
used in conjunction with this accessory.
* 4. Integrated Economizers:
a. Integrated integral modulating type capable
of simultaneous economizer and compressor
operation.
sensor in the conditioned
2