Unitary products group EF-10 User manual

INSTALLATION
INSTRUCTION
CAUTION: READ ALL SAFETY GUIDES BEFORE YOU
BEGIN TO INSTALL YOUR UNIT.
SAVE THIS MANUAL
MODEL: EF-10
O
O
O
OO
208/230/460
VOLT ONLY
SPLIT-SYSTEM HEAT PUMPS
OUTDOOR UNITS
035-18550-001-A-0902
CONTENTS
GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . .4
AGENCY APPROVALS. . . . . . . . . . . . . . . . . . . . . . . . . .4
INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
See the following page for a complete Table of Contents.
NOTES, CAUTIONS AND WARNINGS
Installer should pay particular attention to the words:
NOTE, CAUTION, and WARNING. Notes are intended to
clarify or make the installation easier. Cautions are given
to prevent equipment damage. Warnings are given to
alert installer that personal injury and/or equipment dam-
age may result if installation procedure is not handled
properly.

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2Unitary Products Group
TABLE OF CONTENTS
NOMENCLATURE. . . . . . . . . . . . . . . . . . . . . . . . . . . 3
GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . 4
REFERENCE. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3
AGENCY APPROVALS. . . . . . . . . . . . . . . . . . . . . . . 4
INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
INSTALLATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
LIMITATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
LOCATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
ROOF-TOP LOCATIONS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
GROUND LEVEL LOCATIONS . . . . . . . . . . . . . . . . . . . . . . . . .6
RIGGING AND HANDLING . . . . . . . . . . . . . . . . . . . . . . . .6
CLEARANCES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
COMPRESSORS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
COMPRESSOR CRANKCASE HEATER. . . . . . . . . . . . . . . . . .9
POWER AND CONTROL WIRING . . . . . . . . . . . . . . . . . .9
POWER WIRING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
PHASING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
CONTROL WIRING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
WIRE SIZING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9
REFRIGERANT PIPING . . . . . . . . . . . . . . . . . . . . . . . . .11
GENERAL GUIDELINES . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
LINE SIZING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
SERVICE VALVES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
EXTENDING THE SERVICE PORTS . . . . . . . . . . . . . . .13
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13
EVACUATING AND CHARGING. . . . . . . . . . . . . . . . . . .15
ALTERNATE CHARGING METHODS . . . . . . . . . . . . . . . . . . .16
BALANCE POINT SETTING . . . . . . . . . . . . . . . . . . . . . .16
START-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
CRANKCASE HEATER. . . . . . . . . . . . . . . . . . . . . . . . . .17
PRE-START CHECK. . . . . . . . . . . . . . . . . . . . . . . . . . . .17
INITIAL START-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
PHASING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
GENERAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
SYSTEM SEQUENCE OF OPERATION. . . . . . . . . . . . . 18
COOLING OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
HEATING OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
DEFROST CYCLE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
OPERATION BELOW 0ºF OUTDOOR TEMPERATURE. . . . 20
EMERGENCY HEAT OPERATION . . . . . . . . . . . . . . . . . . . . 20
SAFETY FEATURES. . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
SECURE OWNER’S APPROVAL . . . . . . . . . . . . . . . . . . 21
MAINTENANCE. . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
CLEANING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
LUBRICATION. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
REPLACEMENT PARTS. . . . . . . . . . . . . . . . . . . . . . . . . 21
NOTICE TO OWNER . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
LIST OF FIGURES
Fig. # Pg. #
1 CENTER OF GRAVITY . . . . . . . . . . . . . . . . . . . . . . . . 6
2 TYPICAL RIGGING . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3 POINT LOADS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4 UNIT DIMENSIONS AND CLEARANCES. . . . . . . . . . 8
5 TYPICAL FIELD WIRING . . . . . . . . . . . . . . . . . . . . . 10
6 FIELD PIPING DIAGRAMS . . . . . . . . . . . . . . . . . . . . 12
7 EXTENDING THE SERVICE PORTS . . . . . . . . . . . . 15
8 REFRIGERANT FLOW DIAGRAM . . . . . . . . . . . . . . 15
9 CHARGING CURVE EF-10
(COOLING MODE) . . . . . . . . . . . . . . . . . . . . . . . . . . 17
LIST OF TABLES
Tbl. # Pg. #
1 PHYSICAL DATA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2 UNIT APPLICATION DATA. . . . . . . . . . . . . . . . . . . . . 5
3 ELECTRICAL DATA . . . . . . . . . . . . . . . . . . . . . . . . . 10
4 LIQUID LINES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
5 VAPOR LINES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
6 REFRIGERANT LINE CHARGE . . . . . . . . . . . . . . . . 12

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Unitary Products Group 3
NOMENCLATURE
PRODUCT NOMENCLATURE
OUTDOOR CONDENSING UNITS AND HEAT PUMPS
EF -10 C 00 A T A AA 1 A
Model # Model Number
Description Options
E Product Category H = Air Conditioner Split System E = Heat Pump Split System
F Product Identifier F = R-22 Standard Efficiency 2-Pipe
-10 Nominal Cooling Capacity
MBH
-07 = 7 1/2 Ton
-10 = 10 Ton
CHeatType C = Cooling Only
00 Nominal Heating
Capacity 00 = No Heat Installed
A Airflow Options A = Standard Motor
T Voltage T = 208/230-3-60
W = 460-3-60
A Installation Options A = None
AA Special Options AA = None
AC = Technicoat
1 Generation 1 = First Generation 2nd = Second Generation

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4Unitary Products Group
GENERAL
These heat pump units are designed for outdoor instal-
lation on a roof or at ground level. Every unit is com-
pletely piped and wired at the factory and is shipped
ready for immediate installation. Only the liquid and
vapor lines to the indoor coil, the control wiring and the
main power wiring are required to complete the instal-
lation. Each unit is dehydrated, evacuated, leak tested
and pressure tested at 450 psig before being pressur-
ized with a holding charge of Refrigerant-22 for ship-
ment and/or storage.
Every unit includes a heavy-duty compressor with line
break overload protection, a suction line accumulator,
a 4-way reversing valve, filter-drier, expansion valves,
distributors, check valves, and a copper tube/aluminum
fin coil.
All controls are readily accessible for maintenance,
adjustment and service. All power and control wiring
can be routed through the front of the unit.
SAFETY CONSIDERATIONS
Installer should pay particular attention to the words:
NOTE, CAUTION and WARNING. Notes are intended
to clarify or make the installation easier. Cautions are
given to prevent equipment damage. Warnings are
given to alert the installer that personal injury and/or
equipment damage may result if the installation proce-
dure is not handled properly.
REFERENCE
This instruction covers the installation of the outdoor
unit. For information on the matching indoor, see PN#
035-18877-001.
All accessories come with a separate installation man-
ual. Refer to Parts Manual for complete listing of
replacement parts on this equipment.
The above forms may be ordered from:
Standard Register
2101 W. Tecumseh Rd
Norman, Oklahoma 73069
Toll Free Tel. [phone]
Toll Free Fax. [phone]
AGENCY APPROVALS
Design certified by UL as follows:
1. For use as a cooling/heat pump unit only.
2. For outdoor installation only.
INSPECTION
As soon as a unit is received, it should be inspected for
possible damage during transit. If damage is evident,
the extent of the damage should be noted on the car-
rier's freight bill. A separate request for inspection by
the carrier's agent should be made in writing. See Form
50.15-NM for more information.
Improper installation may create a condition
where the operation of the product could cause
personal injury or property damage.
Improper installation, adjustment, alteration,
service or maintenance can cause injury or
property damage. Refer to this manual for
assistance or additional information, consult a
qualified installer or service agency.
This product must be installed in strict compli-
ance with the enclosed installation instructions
and any applicable local, state, and national
codes including, but not limited to, building,
electrical, and mechanical codes.

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Unitary Products Group 5
INSTALLATION
LIMITATIONS
These units must be installed in accordance with all
national and local safety codes. If no local codes apply,
installation must conform with the appropriate national
codes. See Table 2 for unit application data. Units are
designed to meet National Safety Code Standards. If
components are to be added to a unit to meet local
codes, they are to be installed at the dealer's and/or
the customer's expense.
LOCATION
Use the following guidelines to select a suitable loca-
tion for these units.
1. The outdoor units must be installed outside the
building. The outdoor fans are the propeller type
and are not suitable for use with duct work.
2. The outdoor and indoor units should be installed as
close together as possible and with a minimum
number of bends in the refrigerant piping. Refer to
REFRIGERANT PIPING for additional information.
TABLE 1: PHYSICAL DATA
Description Unit Model EF-10
Compressor1Rating, (Tons) 10
Fans Quantity 2 Diameter, (In.)/No. Blades 24/3
Nominal CFM 7830
Fan Motors2HP 3/4
RPM 1100
Coil
Face Area, (Sq. Ft.) 36.11
Rows Deep x Rows High 2 x 40
Finned Length, (In.) 130
Tube (Copper) OD - inches 3/8
Fins (Aluminum) per inch 20
Refrigerant-22
(Lbs.) Holding Charge 2.25
Operating Charge331.8
Unit Weight
(Lbs.) Shipping 857
1. These compressors are fully hermetic.
2. These PSC motors are directly connected to the outdoor fans and have inherent protection, ball bearings and a 48 frame.
3. Includes outdoor unit and matched indoor blower unit, but no piping. Refer to Table 6 for refrigerant line charge.
TABLE 2: UNIT APPLICATION DATA
MODEL EF-10
Voltage Variation1
Min. / Max.
1. Rated in accordance with ARI Standard 110, utilization
range “A”.
208/230-3-60 187 / 252
460-3-60 432 / 504
Air Temperature on
Outdoor Coil, ºF
Min. / Max.
Cooling 40ºF / 125ºF
Heating 0ºF2/ 75ºF
2. Below 0ºF, the control system stops the compressor
and allows the electric heat accessory to cycle at its
standby capacity.
Air Temperature on
Indoor Coil ºF
Min. / Max.
Cooling 57ºF / 72ºF
Heating 50ºF3/ 80ºF
3. Operation below this temperature is permissible for a
short period of time when a unit is required to heat the
conditoned space up to 50ºF.

035-18550-001-A-0902
6Unitary Products Group
3. The outdoor unit should not be installed beneath
windows or between structures where normal oper-
ating sounds may be objectionable.
4. All units require certain clearances for proper oper-
ation and service. Refer to General Installation
Form 55.70-N1 for additional guidelines.
On either roof top or ground level installations, rubber
padding can be applied between the base rails and
their supports to lessen any transmission of vibration.
ROOF-TOP LOCATIONS
Be careful not to damage the roof. Consult the building
contractor or architect if the roof is bonded. Choose a
location with adequate structural strength to support
the unit.
The unit must be mounted on solid level supports. The
supports can be channel iron beams or wooden beams
treated to reduce deterioration.
A minimum of two (2) beams are required to support
each unit. The beams should: (1) Be positioned per-
pendicular to the roof joists. (2) Extend beyond the
dimensions of the unit to distribute the load on the roof,
(3) Be capable of adequately supporting the entire unit
weight. Refer to Figure 1 and Table 1 for load distribu-
tion and weights.
These beams can usually be set directly on the roof.
Flashing is not required.
NOTE: On bonded roofs, check for special installation
requirements.
GROUND LEVEL LOCATIONS
The units must be installed on a substantial base that
will not settle. Any strain on the refrigerant lines may
cause a refrigerant leak.
A one-piece concrete slab with footers that extend
below the frost line is recommended. The slab should
not be tied to the building foundation because noise
and vibration will telegraph into the building.
A unit can also be supported by concrete piers. These
piers should: (1) extend below the frost line, (2) be
located under the unit's four corners and (3) be sized to
carry the entire unit weight. Refer to Figure 1 and Table
1 for the center of gravity and unit weight.
A gravel bed or some other means of handling the con-
densate that will drop from the underside of the unit coil
during the heating and defrost cycles may have to be
provided.
RIGGING AND HANDLING
Exercise care when moving the unit. Do not remove
any packaging until the unit is near the place of installa-
tion.
Rig the unit by attaching nylon straps with hooks to the
lifting holes provided in the base rails. Spreaders,
whose length exceeds the largest dimension across
the unit, MUST be used across the top of the unit if the
The outdoor unit should not be installed in an
area where mud and/or ice could cause per-
sonal injury. Remember that condensate will
drip from the underside of the unit coils during
heat and defrost cycles and that this conden-
sate will freeze when the temperature of the
outdoor air is below 32°F.
Care should be taken to protect the unit from
tampering and unauthorized persons from
injury. Screws on access panels will prevent
casual tampering. Additional safety precau-
tions such as fences around the unit or locking
devices on the panels may be advisable.
Check local authorities for safety regulations.
FIGURE 1 - CENTER OF GRAVITY
Unit Dim. (In.)
ABCD
10 Ton 76-7/8 39-7/8 38-7/8 16

035-18550-001-A-0902
Unitary Products Group 7
rigging height above the top of the unit is less than 5
feet. See Figure 2.
BEFORE LIFTING A UNIT, MAKE SURE THAT ITS
WEIGHT IS DISTRIBUTED EQUALLY ON THE
STRAPS SO THAT IT WILL LIFT EVENLY.
Units may also be moved or lifted with a fork-lift. Slot-
ted openings in the base rails are provided for this pur-
pose.
LENGTH OF FORKS MUST BE A MINIMUM OF 54"
when lifting from either side.
Remove the nesting brackets from the four corners on
top of the unit. All screws that are removed to take
these brackets off must be replaced on the unit.
Do not use straps under the unit or through the
fork lift slots for lifting purposes. Sharp metal
edges can damage the straps and could result
in personal injury or equipment damage.
FIGURE 2 - TYPICAL RIGGING
Before lifting the unit, make sure that its
weight is distributed equally on the cables so
that it will lift evenly.
SPREADER
BAR
LIFTING
HOLES
FIGURE 3 - POINT LOADS
A
D
B
C
UNIT 4-POINT LOAD (lbs)
TOTAL A B C D
10 Ton 741 258 173 123 187

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8Unitary Products Group
CLEARANCES
All units require certain minimum clearances for proper
operation and service. Refer to Figure 4 for these
clearances.
Additional height may be required for snow clearance if
winter operation is expected.
MINIMUM CLEARANCES
CLEARANCE DESCRIPTION DISTANCE IN
INCHES
Overhead (Top)1
1. Units must be installed outdoors. Overhanging structures or
shrubs should not obstruct condenser air discharge.
120
Front (Piping and Access Panels) 30
Left Side 24
Right Side 24
Rear 24
Bottom2
2. Adequate snow clearance must be provided during winter oper-
ation.
0
Do not permit overhanging structures or shrubs
to obstruct air discharge.
FIGURE 4 - UNIT DIMENSIONS AND CLEARANCES
All dimensions are in inches.
They are subject to change
without notice. Certified
dimensions will be provided
upon request.
Connection
Entry ConnectionSize 15 Ton
Suction Line A 1-1/8 ID
Liquid Line B 5/8 ID
Power Wiring C 2-1/8 KO
Control Wiring D 7/8 KO
AIR
OUT
AIR
OUT
AIR
IN
44-1/4 -
COMPRESSOR AND
FAN MOTOR ACCESS
76-7/8
39 -7/8
OO
O
EXTERNAL PRESSURE
GAUGE FITTINGS
D
C
A
B
6- 3 / 4
EF-10
15-3/4
7-3/4

035-18550-001-A-0902
Unitary Products Group 9
COMPRESSORS
Units are shipped with compressor mountings factory-
adjusted and ready for operation.
COMPRESSOR CRANKCASE HEATER
The compressor is equipped with a crankcase heater
to prevent refrigerant from mixing with crankcase oil
during the “OFF” cycle. The heaters will be energized
when the compressor is not running providing the unit
disconnect switch is closed.
If a unit has just been installed or the unit disconnect
switch has been open for a long period of time, move
the system switch on the room thermostat to the “OFF”
position before closing the unit disconnect switch. Eight
hours of crankcase heat are required to drive the liquid
refrigerant out of the compressor before the compres-
sor can be started.
POWER AND CONTROL WIRING
Install electrical wiring in accordance with the latest
National Electrical Code (NFPA Standard No. 70) and/
or local regulations. The unit should be grounded in
accordance with these codes.
POWER WIRING
Check the voltage of the power supply against the data
on the unit nameplate. Check the size of the power
wire, the disconnect switch and the fuses against the
data on Table 3.
NOTE: Copper conductors must be installed between
the disconnect switch and the unit.
Refer to Figure 4 for the location of the power wire
access opening through the front of the unit. This open-
ing will require a field-supplied conduit fitting.
The field-supplied disconnect switch must be suitable
for an outdoor location. Although it should be installed
near the unit, do NOT secure it to the unit cabinet.
Refer to Figure 5 for typical field wiring.
PHASING
Scroll compressors operate in one direction only, if a
three phase scroll compressor is experiencing:
• Low amperage draw
• Similar discharge and suction pressures
• Increased noise level
then the compressor is operating in reverse. To correct
this condition, switch any two (2) line voltage leads at
the contactor. Please note, single phase scroll com-
pressors will start and run in one direction only. The
reverse operation is not a concern.
CONTROL WIRING
Refer to Figure 5 for the location of the control wire
access opening through the front of the unit.
Route the necessary low voltage control wires (18 Awg
Min) from terminal block TB2 of the unit control box
through this access opening to the indoor unit and to
the room thermostat. Refer to Figure 5 for typical field
wiring.
The room thermostat should be mounted about 5 feet
above the floor and located where it will be exposed to
normal room air circulation. Do not locate it on an out-
side wall, near a supply air grill, or where it may be
affected by sunlight and/or drafts. Circulation of air to
the thermostat should not be blocked by curtains,
drapes, furniture, partitions, etc.
Some installations may require a locking cover to pro-
tect the thermostat from tampering and/or damage.
WIRE SIZING
Refer to the following chart to size the control wiring
properly. If the wiring is undersized, voltage drop could
become excessive and result in malfunctioning of the
unit controls.
Do Not loosen compressor mounting bolts.
Do not attempt to start the compressor without
at least eight hours of crankcase heat or com-
pressor damage will occur.
Units equipped with scroll compressors oper-
ate in one direction only.
Incorrect scroll compressor rotation can dam-
age or fail the compressor(s).

035-18550-001-A-0902
10 Unitary Products Group
FIGURE 5 - TYPICAL FIELD WIRING
035-16602-001
TB1 can be routed
TB1
TB1
TB2
TABLE 3: ELECTRICAL DATA
MODEL VOLTAGE
CODE UNIT POWER SUPPLY
COMPRESSOR1CONDENSER FAN MOTOR UNIT
QTY RLA LRA QTY HP FLA
MINIMUM
CIRCUIT
AMPACITY
(AMPS)
MAXIMUM
FUSE SIZE2
(AMPS)
MINIMUM
DISCONNECTSIZE3
(AMPS)
EF-10 2 208/230/3/60 1 42.0 239.0 2 3/4 3.0 58.5 100 100
4 460/3/60 1 19.2 125.0 2 3/4 1.6 27.2 45 45
1. The 208-230 V compressors and motors use a single tap for the entire range of voltages. The 208/230 V to 24 V transformers
have different taps for 208 and 230 V.
2. Dual element, time delay type.
3. Refer to article NEC/NFPA No. 70, articles 440-11,12 for information on minimum disconnect sizing.

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REFRIGERANT PIPING
GENERAL GUIDELINES
Many service problems can be avoided by taking ade-
quate precautions to provide an internally clean and
dry system and by using procedures and materials that
conform with established standards.
Use hard drawn copper tubing where no appreciable
amount of bending around pipes or other obstructions
is necessary. Use long radius ells wherever possible
with one exception - short radius ells for the traps in all
vapor risers. If soft copper is used, care should be
taken to avoid sharp bends which may cause a restric-
tion.
Pack fiber glass insulation and a sealing material such
as permagum around refrigerant lines where they pen-
etrate a wall to reduce vibration and to retain some
flexibility.
Support all refrigerant lines at minimum intervals with
suitable hangers, brackets or clamps.
Braze all copper to copper joints with Silfos-5 or equiv-
alent brazing material. Do not use soft solder.
Insulate all vapor lines with a minimum of 1/2" ARMA-
FLEX or equal. Liquid lines exposed to direct sunlight
and/or high temperatures must also be insulated.
Never solder vapor and liquid lines together. They can
be taped together for convenience and support pur-
poses, but they must be completely insulated from
each other.
Never exceed the maximum line length listed in
Table 2.
LINE SIZING
The following factors should be considered when locat-
ing the indoor and outdoor units and when sizing the
refrigerant lines for a split heat pump system. Refer to
Figure 6.
THE LIQUID LINE - The vertical rise should never
exceed 50 feet because liquid refrigerant will lose 0.5
psi of static head for each vertical foot.
The total pressure loss for a field-installed liquid line
should never exceed 40 psi because the liquid refriger-
ant could flash before it reaches the expansion valve.
This flashing will not only cause erratic valve operation
and poor system performance, but could also damage
the expansion valve.
Total pressure loss includes the static head loss
explained above plus the friction losses due to the
length of the line (Table 4) and number of fittings in the
line.
When the indoor unit is above the outdoor unit, the fric-
tion loss through the 1-1/8" OD vapor riser will be more
of a limiting factor than the loss of static head in the liq-
uid riser. See Example #3 and #4 for the VAPOR
LINE.
THE VAPOR LINE - A vapor line should not only be
sized for a friction loss of 3 psi (2°F) but also for the
proper return of oil to the compressor during both the
cooling and heating cycles.
Friction loss should always be based on cooling opera-
tion because refrigerant flow rates will be greater dur-
ing the cooling cycle than during the heating cycle.
TABLE 4: LIQUID LINES
System
Model
Refrigerant
FlowRate,1
(Lbs/Min)
1. Based on Refrigerant-22 at the nominal cooling capacity of the system, a liq-
uid temperature of 105ºF and a vapor temperature of 40ºF. Since refrigerant
flow rates will be a little lower at the nominal heating capacity of each sys-
tem, liquid line friction loss should always be based on cooling operation.
Type “L”
Copper
Tubing,
(In. OD)
Pressure Drop2
2. These friction losses do not include any allowance for fittings.
Friction,3
(PSI/100 Ft.)
3. The total pressure drop of the liquid line for both friction and vertical rise
must not exceed 40 PSI. If the pressure drop exceeds 40 PSI, the liquid
refrigerant could flash before it reaches the expansion valve. This flashing
will not only cause erratic valve operation and poor system performance, but
could also damage the expansion valve.
VerticalRise
(PSI/Ft.)
EF-10/FF-10 30.0 5/8 3.5 0.5

035-18550-001-A-0902
12 Unitary Products Group
Oil return will be critical during:
1. The cooling cycle when the outdoor unit is above
the indoor unit (detail 1 of Figure 6).
2. The heating cycle when the indoor unit is above
the outdoor unit (detail 4 of Figure 6).
When the indoor unit is above the outdoor unit, the size
of the vapor riser must be reduced to 1-1/8" OD so that
the velocity of the refrigerant will be great enough to
carry oil up the riser during the heating cycle.
When 1-1/8" OD tubing must be used for the riser, the
maximum length for the vapor line will be greatly
reduced as shown in the following examples.
EXAMPLES:
#1 - 10 Ton System
89 feet of 1-3/8" OD, type “L” copper tubing
(89 feet x 2.8 psi/100 feet) . . . . . . . . . . . . . . . . 2.5 psi
Fitting*. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0.5 psi
Vapor Line Pressure Drop = 3.0 psi
#2 - 10 Ton System
29 feet of 1-1/8" OD, type “L” copper tubing (vertical)
(29 feet x 8.0 psi/100 feet). . . . . . . . . . . . . . . . .2.3 psi
7 feet of 1-3/8" OD, type “L” copper tubing (horizontal)
(7 feet x 2.8 psi/100 feet). . . . . . . . . . . . . . . . . .0.2 psi
Fitting* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.5 psi
Vapor Line Pressure Drop = 3.0 psi
*Determine the pressure drop of the fittings for each installation - DO NOT use
the estimated values as shown in the above examples.
Although longer vapor lines are permissible, friction
losses exceeding 3 psi (2°F) will reduce system capac-
ity in both the cooling and heating cycles.
SERVICE VALVES
These outdoor units have both vapor and liquid line
service valves.
Both valves are shipped from the factory front-seated
and closed with the valve stem in the maximum clock-
wise position.
These service valves are the back-seating type and
have a 1/4" male flare access port for evacuating and
charging the system.
FIGURE 6 - FIELD PIPING DIAGRAMS
(Cooling/Heating Refrigerant Flow)
TABLE 5: VAPOR LINES
System
Model
Refrigerant
Flow Rate,1
(Lbs/Min)
1. Based on Refrigerant-22 at the nominal cooling capacity of the system, a
vapor temperature of 40ºF and a liquid temperature of 105ºF. Since refriger-
ant flow rates will be a little lower at the nominal heating capacity of each sys-
tem, vapor line friction loss should always be based on cooling operation.
Type “L”
Copper Tubing
(In. OD)
Friction
Loss, 2,3
(PSI/100 Ft.)
2. Although vapor lines should be sized for a friction loss equivalent to a 2ºF
change in saturation temperature (or approximately 3 psi), sizing the lines for
the proper return of oil is more important.
3. These friction losses do not include any allowance for fittings. Only use a
1-1/8” riser when the indoor unit is above the outdoor unit.
EF-10 30.0 1-1/8 4.7
1-3/8 1.6
TABLE 6: REFRIGERANT LINE CHARGE1
1. Charges are based on 40ºF suction temperature and 105ºF liquid tempera-
ture.
Refrigerant
Line2
2. Type “L” copper tubing.
Line Size,
OD (In.) Refrigerant Charge (Lb/Ft)
Liquid 5/8 0.113
Vapor 1-1/8 0.013
1-3/8

035-18550-001-A-0902
Unitary Products Group 13
Schrader access valves are provided on the compres-
sor vapor and discharge lines for pressure checking
the system.
All access ports are sealed with a removable cap.
Never remove a cap unless the valve is fully back-
seated with its valve stem in the maximum counter-
clockwise position because the refrigerant charge will
be lost.
EXTENDING THE SERVICE PORTS
Refer to Figure 7:
1. Loosen the screws securing the service ports in
shipping position. (See Figure 7).
2. Push the service ports through the corner post.
3. Tighten the screws to secure the service ports for
installation.
INSTALLATION
Since the condensing units are shipped with a holding
charge of refrigerant-22, they can be checked for a
refrigerant leak by depressing the stem on either of the
service ports that extend through the cabinet. As soon
as some internal pressure is relieved release the stem.
DO NOT release the entire holding charge.
If the unit has already lost its holding charge, it should
be leak tested and the necessary repairs should be
made. If the unit has maintained its holding charge, you
can assume that it has no leaks and proceed with the
installation.
Before installing the liquid line between the outdoor
and indoor units, remove the copper disc from the liq-
uid connection on the outdoor unit per the following
procedure:
1. Make sure the refrigerant in the line has been
recovered and that the liquid service valve on the
unit is front-seated and closed. The valve stem
should be turned to its maximum clockwise posi-
tion.
2. Drill a small hole through the disc before unbrazing
it to permit a flow of dry nitrogen through the con-
nection while it is being unbrazed.
3. Remove the cap from the 1/4" access port on the
liquid line stop valve.
4. Connect a supply of dry nitrogen to this access
port.
5. Unbraze the copper disc from the liquid connection
while maintaining a minimum flow of dry nitrogen
through the connection.
6. Burnish the external surfaces of the liquid connec-
tion on the outdoor unit and the end of the field-
supplied piping being used for the liquid line.
NOTE: Clean surfaces are essential for a well brazed
connection.
7. Carefully clean the internal surfaces of the above.
Any particles left on these surfaces may lead to a
future system malfunction.
NOTE: Use only copper tubing that has been espe-
cially cleaned and dehydrated for refrigerant
use. If the tubing has been open for an
When making a braze connection, wrap a wet
rag around all tubing inside the unit to prevent
damage to the other components.
Dry nitrogen should always be supplied
through a connection while it is being brazed or
unbrazed because the temperature required to
make or break a brazed joint is sufficiently high
to cause oxidation of the copper unless an inert
atmosphere is provided. The flow of nitrogen
should be continued until the joint has cooled.
The dry nitrogen must always be supplied
through a pressure regulating valve.
This hole is also required to prevent the inter-
nal pressure from building up as the disc is
being unbrazed and from blowing the disc off.
This warning applies to any disc being
removed from a service valve, coil connection,
etc.

035-18550-001-A-0902
14 Unitary Products Group
extended period of time, it should be cleaned
before being used.
The liquid line connections can now be brazed while
maintaining a minimum flow of dry nitrogen through the
piping.
NOTE: A filter-drier is factory-mounted in the outdoor
unit for the heating cycle and in the indoor unit
for the cooling cycle.
Do NOT install another filter-drier in the field-
supplied liquid line because refrigerant will
flow in both directions on a heat pump system.
1. The matched air handlers are shipped with a small
R-22 charge and they should be checked for leaks
before installation. Drill a small hole through the
sealing cap or disc in both the liquid and suction
connection. If there is a pressure release, the
evaporator has no leaks and you can proceed with
installation. If the charge has been lost, the coils
should be leak tested and the necessary repairs
made.
2. Move the dry nitrogen supply from the access port
on the liquid line service valve of the outdoor unit to
the hole through the vapor disc on the indoor unit.
3. Unbraze the coil's liquid line disc while maintaining
a flow of dry nitrogen across the connection and
through the hole in the liquid line disc.
4. After the disc has been removed, burnish the exter-
nal surfaces and clean the internal surfaces as out-
lined above.
5. Move the dry nitrogen supply back to the access
port on the liquid line service valve.
6. Braze the liquid line to the liquid connection on the
indoor unit while maintaining a minimum flow of dry
nitrogen through the liquid line, the indoor coil and
the hole in the vapor disc.
7. Unbraze the disc on the vapor connection of the
indoor unit while maintaining the flow of dry nitro-
gen.
8. After the disc has been removed, burnish the exter-
nal surfaces and clean the internal surfaces as out-
lined above.
The vapor piping can now be brazed to the vapor con-
nection on the indoor unit while maintaining a minimum
flow of dry nitrogen.
Before brazing the vapor line to the outdoor unit, make
sure the refrigerant in the line has been recovered,
then remove the copper disc from its vapor connection
per the following procedure:
1. Make sure that the vapor line service valve on the
outdoor unit is front-seated and closed with its
valve stem in the maximum clockwise position.
2. Drill a small hole through the disc before unbrazing
it to permit a flow of dry nitrogen through the con-
nection while its being unbrazed.
3. Move the dry nitrogen supply to the access port on
the vapor line service valve of the outdoor unit.
4. Unbraze the disc on the vapor line connection of
the outdoor unit while maintaining a minimum flow
of dry nitrogen through the access port of the vapor
line service valve and the hole in the vapor disc.
5. After the disc has been removed, burnish the exter-
nal surfaces and clean the internal surfaces of the
vapor connection and the vapor piping.
The vapor line can now be brazed to the vapor connec-
tion on the outdoor unit while maintaining the flow of
dry nitrogen.
After the liquid and vapor lines have been installed, the
system should be evacuated and charged.

035-18550-001-A-0902
Unitary Products Group 15
EVACUATING AND CHARGING
With the liquid and suction line service valves closed,
connect a vacuum pump through a charging manifold
to the access ports on both the liquid and suction line
service valves.
NOTE: The vacuum pump connection should be short
and no smaller than 3/8" O.D.
The refrigerant lines and the indoor coil must now be
evacuated to 500 Microns without disturbing the
charge in the condenser coil or the compressor.
After proper evacuation and dehydration, charge refrig-
erant through the access port on the liquid line service
valve allowing the vacuum to draw in as much refriger-
ant as possible.
To continue charging refrigerant in the cooling mode,
open the liquid and the vapor line service valves fully.
Turn the stem of the liquid service valve clockwise 1/4
turn to open its access port for reading pressure.
Start the compressor (after 8 hours of crankcase heat),
turn the stem of the vapor line service valve clockwise
1/4 turn to open its service port and continue to charge
refrigerant gas through this suction access port until
you meet the conditions shown on the charging curve,
Figure 9.
Open the liquid and vapor line service valves fully to
close their access ports after the system has been
charged.
FIGURE 7 - EXTENDING THE SERVICE PORTS
COPPER
2SCREWS
CORNER
POST
SERVICE PORTS IN SHIPPING POSITION
UNIT WALL
SIDE VIEW
COPPER
TUBE
UNIT
WALL
COPPER
2SCREWS
CORNER
POST
TOP VIEW
UNIT
WALL
LOOSEN
SCREWS
SIDE VIEW
(AS SHIPPED)
PUSH SERVICE
PORTS THROUGH
CORNER POST
TIGHTEN SCREWS
SIDE VIEW
SERVICE PORTS
EXTENDED
()
SERVICE PORTS
EXTENDED
()
SERVICE PORTS IN INSTALLED POSITION
Do not charge liquid refrigerant through the
compressor suction connection.
Do not attempt to start the compressor without
at least 8 hours of crankcase heat or compres-
sor damage will occur.

035-18550-001-A-0902
16 Unitary Products Group
ALTERNATE CHARGING METHODS
If you are starting a unit when the ambient temperature
is higher or lower than those shown in Figure 9, either
of the following methods may be used.
Method 1: Determine the total weight of the refriger-
ant for the total system by adding the
required charge for the outdoor unit, the
indoor unit and the refrigerant lines using
information in Tables 1 (Physical Data)
and 6 (Refrigerant Line Charge). Using the
charging procedures outlined above,
weigh the required amount of refrigerant
charge into the unit.
Method 2: Install a field supplied moisture indicating
sight glass in the liquid line between the fil-
ter-drier and the evaporator coil.
Using the charging procedure outlined
above, charge refrigerant until the mois-
ture indicating sight glass is clear. Add
approximately 1 extra pound of refrigerant
to assure a liquid refrigerant seal at the
expansion valve under all operating condi-
tions. Block the flow of the condenser air, if
necessary, to assure a head pressure of
280 psig during the charging procedure.
NOTE: The installer should return to the job to verify
the operating charge when the ambient tem-
perature is within the conditions shown in Fig-
ure 9.
BALANCE POINT SETTING
The balance point of a heat pump is the lowest temper-
ature at which the refrigeration system can heat the
building without any supplemental resistance heat.
The balance point is dependent upon -
1. The outdoor design temperature,
2. The building heat loss at the outdoor design tem-
perature, and
3. The heating capacity of the system at the outdoor
design temperature.
Refer to Form 515.41-AD1 to determine balance point.
Refer to Form 690.63-N1V for details regarding the
outdoor ambient balance point control accessory
Model No. 2BP11700224.
FIGURE 8 - REFRIGERANT FLOW DIAGRAM

035-18550-001-A-0902
Unitary Products Group 17
START-UP
CRANKCASE HEATER
The crankcase heaters must be energized at least 8
hours before starting the compressor. To energize the
crankcase heaters, the main disconnect switch must
be closed. During this 8 hour period, the system switch
on the room thermostat must be “OFF” to prevent the
compressor from starting.
Make sure that the bottom of the compressor is warm
to the touch to prove crankcase heater operation.
PRE-START CHECK
Before starting the unit, complete the following check
list:
1. Have sufficient clearances been provided?
2. Has all foreign matter been removed from the inte-
rior of the unit (tools, construction or shipping
materials, etc.)?
3. Have the outdoor fans been rotated manually to
check for free rotation?
4. Are all wiring connections tight?
5. Does the available power supply agree with the
nameplate data on the unit?
6. Have the fuses, disconnect switch and power wire
been sized properly?
7. Are all compressor hold-down nuts properly
secured?
8. Are any refrigerant lines touching each other or any
sheet metal surface? Rubbing due to vibration
could cause a refrigerant leak.
9. Are there any visible signs of a refrigerant leak,
such as oil residue?
10. Is any electrical wire laying against a hot refrigerant
line? Keep in mind that this unit has a reverse cycle
and that different lines will be hot during the
“HEAT” and “COOL” cycles. Only two lines will
FIGURE 9 - CHARGING CURVE EF-10 (COOLING MODE)
Do not attempt to start the compressor without
at least 8 hours of crankcase heat or compres-
sor damage will occur.

035-18550-001-A-0902
18 Unitary Products Group
remain cool for all cycles - the line between the
compressor and the accumulator and the line
between the accumulator and the reversing valve.
INITIAL START-UP
1. Supply power to the unit through the disconnect
switch prior to starting the compressor.
2. Move the system switch on the room thermostat to
the “COOL” position, and lower its set point to
energize both the compressor and the reversing
valve. Cool air will be supplied to the conditioned
space.
3. Check the compressor amperage. It should not
exceed the RLA rating printed on the unit data
plate or in Table 3 unless the ambient temperature
is above 105°F.
4. Move the system switch on the room thermostat to
the “HEAT” position, and increase the set point of
the room thermostat until heating is required. The
compressor will run, but the reversing valve will be
de-energized. Warm air will be supplied to the con-
ditioned space.
5. Check the operation of the indoor unit per Form
515.41-N2.
6. Check the entire system for refrigerant leaks.
7. Check for any abnormal noises and/or vibrations,
and make the necessary adjustments to correct
(e.g. fan blade touching shroud, refrigerant lines
hitting on sheet metal, etc.)
8. After the unit has been operating for several min-
utes, shut off the main power supply at the discon-
nect switch and inspect all factory wiring
connections and bolted surfaces for tightness.
PHASING
Scroll compressors operate in one direction only. If a
three phase scroll compressor is experiencing:
• Low amperage draw
• Similar discharge and suction pressures
• Increased noise level
then the compressor is operating in reverse. To correct
this condition, switch any two (2) line voltage leads at
the contactor. Please note, single phase scroll com-
pressors will start and run in one direction only. The
reverse operation is not a concern.
OPERATION
GENERAL
During the cooling cycle, when the reversing valve
solenoid becomes energized, operation will be the
same as any conventional air conditioning system.
During the heating cycle, when the reversing valve
solenoid becomes de-energized, compressor dis-
charge gas will be diverted to the indoor coil and the
outdoor coil will become the evaporator.
Refer to Figure 8 for illustration showing the flow of
refrigerant through a heat pump system.
SYSTEM SEQUENCE OF OPERATION
The following sequences of operation are based on
using the manual changeover thermostat. Refer to the
respective unit wiring diagram.
COOLING OPERATION
1. The following controls will be energized through
terminal O on the thermostat to put the system in
the cooling mode.
• Relay RW (460 volt units) and RVS (230 volt
units) and reversing valve solenoid.
2. If the fan switch on the thermostat is in the “ON”
position, indoor section blower motor contactor
10M will be energized through terminal G to
Units equipped with scroll compressors oper-
ate in one direction only.
Incorrect scroll compressor rotation can dam-
age or fail the compressor(s).
Reversing valves and check valves are precise
mechanical devices and will not tolerate any
mechanical abuse such as hammering. If a
refrigerant system isn't properly cleaned after a
compressor burn-out, scale may build up at
these devices and prevent them from operating
properly.

035-18550-001-A-0902
Unitary Products Group 19
provide continuous blower operation. If the switch
is in the “AUTO” position, the blower will operate
only when the thermostat calls for cooling
operation.
3. When TC1 of the thermostat closes on a demand
for cooling, a circuit is made from terminal Y
through the defrost control board and safety
switches to energize contactor 1M (on 460 volt
units) and relay RY1 to start the compressor. Con-
tactor 2M is energized through the NO contacts of
RY1-1 (on 460 volt units) and the NC contacts of
K2 on the defrost control board in order to start the
outdoor fan motors.
4. Relay RY1 also prevents the 10KW portion of
accessory electric heat referenced as standby
electric heat from being utilized whenever the com-
pressor is in operation. This part of the circuit is
covered under HEATING OPERATION.
5. The thermostat will cycle the unit to satisfy the
cooling requirements of the conditioned space.
6. After the unit has shutdown from a cooling cycle or
a power interruption, the anti-short cycle feature of
the defrost control board will not permit the unit to
restart for 5 minutes. This feature prevents the unit
from short cycling.
7. If the discharge pressure reaches 430 psig, the HP
control will open and the defrost control board will
lock out the compressor. If the discharge tempera-
ture reaches 255°F, 2TH thermostat will open and
the defrost control board will lock out the compres-
sor. If the suction pressure falls to 7 psig, the low
pressure switch will open and the defrost control
will lock out the compressor.
8. If the control that caused the lockout has automati-
cally reset, the unit can be restarted by one of the
following:
a. Turning the system switch on the thermostat to the
“OFF” position and back to the “COOLING” position.
b. Increasing the set point on the thermostat above the
temperature in the conditioned space and then
returning it to its original setting.
Opening and closing the power supply main disconnect
switch.
IN ALL THREE RESET METHODS DESCRIBED
ABOVE, A FIVE MINUTE TIME DELAY WILL TAKE
PLACE AFTER THE RESET BEFORE THE UNIT
WILL RESTART.
HEATING OPERATION
1. Reversing valve is de-energized and the system
will be in the heating mode.
2. If the fan switch on the thermostat is in the “ON”
position, indoor section blower motor contactor
10M will be energized through terminal G to pro-
vide continuous blower operation. If the switch is in
“AUTO” position, the blower will operate only when
thermostat calls for heating operation.
3. When the TH1 of the thermostat closes for first-
stage heat, a circuit is made from terminal Y
through the defrost control board and safety
switches to energize contactor 1M (on 460 volt
units) and RY1 to start the compressor. Contactor
2M is energized through the NO contacts of RY1-1
(on 460 volt motors) and the NC contacts of K2 on
the defrost control board, which starts the outdoor
fan motors.
4. The thermostat will cycle the unit to satisfy the
heating requirements of the conditioned space.
5. After the unit has shutdown from a heating cycle or
a power interruption, the anti-short cycle feature of
the defrost control board will not permit the unit to
restart for 5 minutes. This feature prevents the unit
from short cycling.
6. If the discharge pressure reaches 430 psig, the HP
control will open and the defrost control board will
lock out the compressor. If the discharge tempera-
ture reaches 255°F, 2TH thermostat will open and
the defrost control board will lock out the compres-
sor. If the suction pressure falls to 7 psig, the low
pressure switch will open and the defrost control
will lock out the compressor.
7. If the control that caused the lockout has automati-
cally reset, the unit can be restarted by one of the
following:
a. Turning the system switch on the thermostat to
the “OFF” position and back to the “HEATING”
position.
b. Decreasing the set point on the thermostat
below the temperature in the conditioned space
and then returning it to its original setting.
c. Opening and closing the power supply main dis-
connect switch.
IN ALL THREE RESET METHODS DESCRIBED
ABOVE, A FIVE MINUTE TIME DELAY WILL TAKE
PLACE AFTER THE RESET BEFORE THE UNIT
WILL RESTART.

035-18550-001-A-0902
20 Unitary Products Group
8. Supplemental electric heat (if installed) will be con-
trolled by second stage TH2 of the thermostat. The
supplemental electric heat circuit is controlled
through low voltage terminals W, 60 and 66. The
standby portion of electric heat (controlled through
low voltage terminal 53) cannot operate because
relay RY1 is energized, opening the circuit to termi-
nal 53, whenever the compressor is operating.
9. When second stage heating TH2 is satisfied, the
supplemental heaters will be de-energized.
DEFROST CYCLE
When condensate freezes on the outdoor coil during
heating operation, it must be defrosted before it blocks
the flow of air across the coil.
1. A defrost cycle will be initiated by the defrost con-
trol board's timed defrost feature.
2. When the defrost cycle is initiated, the unit oper-
ates as follows:
a. The reversing valve solenoid is energized through
the defrost control board causing the unit to switch
to the cooling cycle.
b. Defrost control board de-energizes 2M contactor,
causing the outdoor section fan(s) to shut down.
c. Supplemental electric heat (if installed) will be ener-
gized through defrost control board. Only that por-
tion of electric heat controlled through low voltage
control terminal 66 will be energized by the defrost
cycle. The operation of supplemental electric heat
during unit defrost will prevent cold drafts in the con-
ditioned space.
3. The defrost cycle will be terminated when:
a. the liquid temperature exceeds 55°F, or
b. 10 minutes have passed since defrost initiation.
The 10 minute cycle time (independent of liquid line
temperature) is controlled by the defrost control board.
4. At defrost termination, the unit returns to the nor-
mal heating operation.
OPERATION BELOW 0°F OUTDOOR TEMPERATURE
1. At 0°F outdoor temperature, the low temperature
compressor cutoff thermostat 1TH contacts 1 and 3
will open, de-energizing contactor 1M which shuts
down the compressor. Contacts 1 and 2 of thermo-
stat 1TH are closed when contacts 1 and 3 are
open. This feature allows the standby electric heat
(if installed) to operate under control of first stage
heating TH1 of the room thermostat whenever the
compressor is shut-down by the 1TH control. The
supplemental electric heat will continue to be con-
trolled by the second stage TH2 of the room ther-
mostat same as described under Item 8 of
HEATING OPERATION.
2. The indoor section blower operation will be con-
trolled by the first stage heating TH1 of the room
thermostat if the fan switch is in the “AUTO” posi-
tion.
EMERGENCY HEAT OPERATION
When the system switch on the room thermostat is
placed in the EMERGENCY HEAT position, operation
is as follows:
1. The emergency heat light on the room thermostat
will be energized.
2. Compressor will not operate because the Y circuit
of the room thermostat cannot be energized.
3. Supplemental and standby electric heat (if
installed) will be controlled by first stage heating
TH1 of room thermostat.
4. Indoor section blower will also be controlled by first
stage heating TH1 if fan switch is in the “AUTO”
position.
SAFETY FEATURES
1. All condenser fan motors have inherent protection
with automatic reset.
2. Every compressor is internally protected against
over current, excessive temperature and primary
single phasing.
This protection is provided by a line break motor
protector that is mounted inside the compressor
housing and is connected between each winding
and the common terminal.
3. Every compressor is protected by crankcase heat-
ers to prevent refrigerant from accumulating in the
crankcases of the compressor during an “OFF”
cycle.
4. All condenser fan motors and the secondary of
every transformer is grounded.