User`s manual

6. (ompare actual suction=robe temperature with desired
suction-robe temperature [sing a tolerance of" + 3°F, add
refiigerant if"actual temperature is more than 3C>Fhighe* than
proper suction=tube temperature, or remove rel'rigerant if
actual ternperatme is more than 3C>Flower than required
suction-tube temperature
NOTE: If the problem causing the inaccurate readings is a
refrigerant leak, refer to the Cheek_br R@'igeras_t Leaks section
INDOOR AIRFLOW AND AIRFLOW ADJUSTMENTS
For cooling operation, the recommended airflow is 350 to 450
cIi*n fPr each 12,000 Btuh of rated cooling capacity. For
heating operation, the airflo_ must produce a temperature rise
that falls within the range stamped on the unit rating plate
Table 7 shows the temperature rise at various airflow rates Tables
11 and 13 show both heating and cooling airflows at various
external static pressures. Refer to these tables to determine the
airflow for the system being installed (See Tables 14 and 15 for
wet coil pressure &up).
NOTE: Be sure that all supply- and return-air grilles are open,
fi'ee fi'om obstrnctions, and adjusted properly
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Be%re changing blower speed, shut off gas supply. Lhen
disconnect electrical power to the unit and install lockout tag.
Electrical shock or explosion can cause serious injury or
death.
Airflow can be changed by changing the lead connections of the
blower motor.
Unit 48GS two- or three=speed motors (except size 030) are
iactory wired ibr tow speed operation. Unit 48GS030 is factoQ'
wired for medium speed
All 4gGX units are factory wired fbr tow speed and may need to
be wired for medium or high speed in the field.
For 208/230V
For color coding on the 208/230V motor leads, see Table 9.
Table 9=Color Coding for 2081230=V Motor Leads
3=SPEED 2-SPEED
Naek = high speed black = high speed
blue = medium speed
red = low speed red = low speed
To change the speed of the blower motor (BM), remove the ihn
motor speed leg lead fi'om the blower relay (BR). This wire is
attached to terminal BM of the integrated gas control (IG() board
_br single- and 3=phase traits. To change the speed, remove and
replace with lead for desired blower motor speed. Inszdate the
removed lead lo avoid contact u,ith cha,ssi,spartx.
For 460=V GE Motors
For color coding on the 460=v GE motor teads, see Table 10.
To change the speed of the blower motor (BM), remove fan motor
speed lead from t!_e blower relay (BR) and replace with the lead
_br the desired blower motor speed. The motor speed lead is
attached to terminal BM of the integrated gas control (IGC) board
For low and mediunl speeds, black must be connected to the
jmalper wire i.s_d.te removed lead e_d to redid cu_tact nith
eha,s,sispart:,'. To select high speed on 460-v GE motors, separate
TaNe 10-Color Coding for 460-V GE Motor Leads
3-SPEED 2=SPEED
black = high speed black = high speed
violet = jumper blue = jumper
orange = medium speed
red = low speed red = tow speed
the black (female quick connect QC fi'om the jumper lead
(male quick connect QC) and connect the black lead to the BR
Ii_,s_date the imnl_er to redid eonlaet _itll a'/_3 c,Sla,s,sispargx.
COOLING SEQUENCE OF OPERATION
With the room them?ostat SYSTEM switch in the COOL position
and the FAN switch in the AUTO. position, the cooling sequence
of operation is as follows:
1. When the room temperature rises to a point that is slightly
above the cooling control setting of t!-_e them?ostat, the
thermostat completes the circuit between _hermostat terminal
R to terminals Y and G. These completed circuits through the
thermostat:
2. The normally open contacts of energized contactor (() close
and complete the circuit through compressor motor (COMP)
to condenser (outdoor) t5n motor (OFM). Both motors start
instantly.
3. The set of normally open contacts of energized relay BM close
and complete the circuit through evaporator blower (indoor)
_hn motor (IFM),
NOTE: (:)nee the compressor has started and then 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 tl-_is point, the thermostat "breaks" tl-_e circuit
between thermostat tem_inal R to terminals Y and G. These open
circuits deenergize contactor coil (. The condenser and compres-
sor motors stop. After a 30=sec. delay, the blower motor stops. The
unit is in a "standby" condition, waiting for the next "call _br
cooling" fiom the room thermostat.
MAINTENANCE
To ensure continuing high per_brmance and to minimize the
possibility of premature equipment failure, periodic maintenance
must be per_brmed on this equipment This combination
heating/cooling unit should be inspected at least once each year by
a qualified stun'ice person. To troubleshoot cooling or heating of
units, refer to Tables 16 18.
NOTE: Consult your local dealer about the availability of a
l'naintenance contract
The ability to properly per%m_ maintenance on this equip=
ment requires certain expertise, mechanical skills, tools, and
equipment. If you do not possess these, do not attempt to
perform any maintenance on this equipment other than those
procedures recommended in the User's Manual. FAILURE
TO HEED THIS WARNING (OULD RESULT IN SERI=
OUS INJURY AND POSSIBLE DAMAGE TO THIS
EQUIPMENT.
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