Bryant 701A - Manual (Page 16)

G. FOR 460-V GE MOTORS
For color coding on the 460-v GE motor leads, see Table 7.
To change the speed of the indoor fan motor (IFM), remove fan
motor speed lead from the time delay relay (TDR) and replace with
the lead for the desired blower motor speed. The motor speed lead
is attached to terminal–3 of TDR. For low and medium speeds
black must be connected to the jumper wire. Insulate removed lead
end to avoid contact with chassis parts. To select high speed on
460-v GE motors, separate the black female quick connect (QC)
from the jumper lead male quick connect (QC) and connect the
black lead to the BR. Insulate the jumper to avoid contact with any
chassis parts.
H. COOLING SEQUENCE OF OPERATION
With the room thermostat SYSTEM switch in the COOL position
and the FAN switch in the AUTO position, the cooling sequence
of operation is as follows:
When the room temperature rises to a point that is slightly above
the cooling control setting of the thermostat, the thermostat
completes the circuit between thermostat terminal R to terminals Y
and G. These completed circuits through the thermostat connect
contactor coil (C) (through unit wire Y) and time delay relay
(TDR) (through unit wire G) across the 24-v secondary of
transformer (TRAN).
The normally open contacts of energized contactor (C) close and
complete the circuit through compressor motor (COMP) to con-
denser (outdoor) fan motor (OFM). Both motors start instantly.
The set of normally open contacts of energized relay TDR close
and complete the circuit through evaporator blower (indoor) fan
motor (IFM).
NOTE: Once the compressor has started and then has stopped, it
should not be started again until 5 minutes have elapsed.
The cooling cycle remains “on” until the room temperature drops
to a point that is slightly below the cooling control setting of the
room thermostat. At this point, the thermostat “breaks” the circuit
between thermostat terminal R to terminals Y and G. These open
circuits deenergize contactor coil C and relay coil TDR. The
condenser and compressor motors stop. After a 30-second delay,
the blower motor stops. The unit is in a “standby” condition,
waiting for the next “call for cooling” from the room thermostat.
MAINTENANCE
To ensure continuing high performance, and to minimize the
possibility of premature equipment failure, periodic maintenance
must be performed on this equipment. This cooling unit should be
inspected at least once each year by a qualified service person. To
troubleshoot heating or cooling of units, refer to tables at the back
of the book.
The following are 701A Cooling Charging Charts:
The following are 702A Cooling Charging Charts:
NOTE TO EQUIPMENT OWNER: Consult your local dealer
about the availability of a maintenance contract.
WARNING: The ability to properly perform mainte-
nance on this equipment requires certain expertise, me-
chanical skills, tools, and equipment. If you do not
possess these, do not attempt to perform any maintenance
on this equipment other than those procedures recom-
mended in the User’s Manual. FAILURE TO HEED
THIS WARNING COULD RESULT IN SERIOUS PER-
SONAL INJURY AND POSSIBLE DAMAGE TO THIS
EQUIPMENT.
WARNING: Failure to follow these warnings could
result in serious personal injury:
1. Turn off electrical power to the unit and install lockout
tag before performing any maintenance or service on
the unit.
2. Use extreme caution when removing panels and parts.
As with any mechanical equipment, personal injury
can result from sharp edges, etc.
3. Never place anything combustible either on, or in
contact with, the unit.
CAUTION: Errors made when reconnecting wires may
cause improper and dangerous operation. Label all wires
prior to disconnection when servicing.
The minimum maintenance requirements for this equipment are as
follows:
1. Inspect air filter(s) each month. Clean or replace when
necessary.
2. Inspect indoor coil, drain pan, and condensate drain at least
each cooling season for cleanliness. Clean when necessary.
3. Inspect blower motor and wheel for cleanliness and check
lubrication each heating and cooling season. Clean when
necessary.
4. Check electrical connections for tightness and controls for
proper operation each heating and cooling season. Service
when necessary.
5. Ensure electric wires are not in contact with refrigerant
tubing or sharp metal edges.
A. AIR FILTER
CAUTION: Never operate the unit without a suitable air
filter in the return-air duct system. Always replace the
filter with the same dimensional size and type as origi-
nally installed. See Tables 1 and 2 for recommended filter
sizes.
Inspect air filter(s) at least once each month and replace
(throwaway-type) or clean (cleanable-type) at least twice during
each heating and cooling season or whenever the filter(s) becomes
clogged with dust and lint.
B. EVAPORATOR BLOWER AND MOTOR
NOTE: All motors are prelubricated. Do not attempt to lubricate
these motors.
For longer life, operating economy, and continuing efficiency,
clean accumulated dirt and grease from the blower wheel and
motor annually.
TABLE 6—COLOR CODING FOR 208/230–V MOTOR
LEADS
3-SPEED 2-SPEED
black = high speed black = high speed
blue = medium speed -
red = low speed red = low speed
TABLE 7—COLOR CODING FOR 460-V GE MOTOR
LEADS
3-SPEED 2-SPEED
black = high black = high
violet = jumper blue = jumper
orange = medium -
red = low red = low
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