Unitary products group EF-07 User manual

INSTALLATION
INSTRUCTION
CAUTION: READ ALL SAFETY GUIDES BEFORE YOU
BEGIN TO INSTALL YOUR UNIT.
SAVE THIS MANUAL
MODEL: EF-07
208/230/460
VOLT ONLY
SPLIT-SYSTEM HEAT PUMPS
OUTDOOR UNITS
035-18547-001-A-0902
CONTENTS
GENERAL 4
SAFETY CONSIDERATIONS . . . . . . . . . . . . . . . . . . . . .4
AGENCY APPROVALS. . . . . . . . . . . . . . . . . . . . . . . . . .4
INSPECTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
START-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .18
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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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. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
GROUND LEVEL LOCATIONS . . . . . . . . . . . . . . . . . . . . . . . . .6
RIGGING AND HANDLING . . . . . . . . . . . . . . . . . . . . . . . .6
CLEARANCES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7
COMPRESSORS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
COMPRESSOR CRANKCASE HEATER. . . . . . . . . . . . . . . . . .8
POWER AND CONTROL WIRING . . . . . . . . . . . . . . . . . .8
POWER WIRING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
CONTROL WIRING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
WIRE SIZING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8
REFRIGERANT PIPING . . . . . . . . . . . . . . . . . . . . . . . . .10
GENERAL GUIDELINES . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
LINE SIZING. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10
SERVICE VALVES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
EXTENDING THE SERVICE PORTS . . . . . . . . . . . . . . .12
INSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .12
EVACUATING AND CHARGING. . . . . . . . . . . . . . . . . . .14
ALTERNATE CHARGING METHODS . . . . . . . . . . . . . . . . . . .15
BALANCE POINT SETTING . . . . . . . . . . . . . . . . . . . . . .15
START-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
CRANKCASE HEATER. . . . . . . . . . . . . . . . . . . . . . . . . .17
PRE-START CHECK. . . . . . . . . . . . . . . . . . . . . . . . . . . .17
INITIAL START-UP . . . . . . . . . . . . . . . . . . . . . . . . . . . . .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 UNIT DIMENSIONS AND CLEARANCES -
7-1/2 TON . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4 TYPICAL FIELD WIRING . . . . . . . . . . . . . . . . . . . . . . 9
5 FIELD PIPING DIAGRAMS . . . . . . . . . . . . . . . . . . . . 11
6 EXTENDING THE SERVICE PORTS . . . . . . . . . . . . 14
7 REFRIGERANT FLOW DIAGRAM . . . . . . . . . . . . . . 16
8 CHARGING CURVE EF-07
(COOLING MODE . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
LIST OF TABLES
Tbl. # Pg. #
1 PHYSICAL DATA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2 UNIT APPLICATION DATA. . . . . . . . . . . . . . . . . . . . . 5
3 ELECTRICAL DATA . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4 LIQUID LINES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
5 VAPOR LINES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
6 REFRIGERANT LINE CHARGE . . . . . . . . . . . . . . . . 12

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NOMENCLATURE
PRODUCT NOMENCLATURE
OUTDOOR CONDENSING UNITS AND HEAT PUMPS
HF -10 C 00 A T A AA 1 A
Model # Model Number
Description Options
H 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
B = Disconnect
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, a filter-drier, an expansion
valve, a distributor, a check valve, 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 installation of the matching
indoor unit, refer to Part Number 035-18548-001.
All accessories come with a separate installation man-
ual. Refer to Parts Manual for complete listing of
replacement parts on this equipment.
The above form may be ordered from:
Standard Register
2101 W. Tecumseh Rd.
Norman, OK 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.
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.
Improper installation may create a condition
where the operation of the product could cause
personal injury or property damage.

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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.
3. The outdoor unit should not be installed beneath
windows or between structures where normal
operating 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.
TABLE 1: PHYSICAL DATA
MODEL EF-07
Compressor1
1. These compressors are fully hermetic.
Rating, (Tons) 7-1/2
Fans Quantity 2 Diameter, (In.)/No. Blades 24/3
Nominal CFM 7600
Fan Motors2
2. These PSC motors are directly connected to the outdoor fans and have
inherent protection, ball bearings and a 48” frame.
HP 3/4
RPM 1100
Coil
Face Area, (Sq. Ft.) 24.00
Rows Deep x Rows High 2 x 36
Finned Length, (In.) 96
Tube (Copper) OD - inches 3/8
Fins (Aluminum) per inch 16
Refrigerant-22
(Lbs.)
Holding Charge 2.25
Operating Charge3
3. Includes outdoor unit and matched indoor blower unit, but no piping. Refer to
Table 6 for refrigerant line charge.
18.8
Pumpdown Capacity4
4. Based on a 95ºF ambient.
24.6
Unit Weight
(Lbs.) Shipping 510
Operating 505
TABLE 2: UNIT APPLICATION DATA
Voltage Variation (Min/Max.)1
1. Rated in accordance with ARI Standard 100, utilization range “A”.
208/230-3-60
460-3-60 187/252 432/504
Air Temperature on OUTDOOR Coil, ºF
Minimum Maximum
Cool Heat Cool Heat
40db 0db2
2. Below 0ºF, the control system stops the compressor and allows the electric
heat accessory to cycle at its standby capacity.
115db 75db
Air Temperature on INDOOR Coil, ºF
Minimum Maximum
Cool Heat Cool Heat
57wb 50db3
3. Operation below this temperature is permissible for a short period of time
when a unit is required to heat the conditioned space up to 50ºF.
72wb 80db
Maximum Line Lengths - 125 ft.
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.

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6Unitary Products Group
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
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.
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
7-1/2 Ton 70-1/8 32 29-5/8 16-1/2
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.

035-18547-001-A-0902
Unitary Products Group 7
CLEARANCES
All units require certain minimum clearances for proper
operation and service. Refer to Figure 3 for these
clearances.
Additional height may be required for snow clearance if
winter operation is expected.
CLEARANCES
FIGURE 2 - TYPICAL RIGGING
W ARNING
B e fo re liftin g th e u n it,
m a k e s u re th a t its w e ig h t
is distributed equally on
the cables so that it w ill
lift e v e n ly
SPREADER
BAR
LIFTIN G
HOLES
Do not permit overhanging structures or shrubs
to obstruct air discharge.
Overhead (Top)1
1. Units must be installed outdoors. Overhanging structures or shrubs should
not obstruct air discharge outlet.
120”
Front
(Piping and Access Panels) 30”
Left Side 24”
Right Side 24”
Rear 24”
Bottom2
2. Adequate snow clearance must be provided if winter operation is expected.
0”
FIGURE 3 - UNIT DIMENSIONS AND CLEARANCES - 7-1/2 TON
AIR
OUT
AIR
IN
AIR
OUT
2-3/4
32
2-1/4
32-1/2 70-1/2
8-3/4
5-3/8
CONTROL BOX
ACCESS
SERVICE
PORT
LOCATION 39 1-1/8 OD
SUCTION LINE
5/8 OD
LIQUID LINE
15-3/4
7/8 DIA
CONTROL WIRING
ENTR
COMPRESSOR AND
CONDENSER FAN MOTOR
ACCESS
1-3/8 DIA.
POWER WIRING
ENTR
6-3/4
CONDENSER FAN MOTOR
ACCES S
7/8" KNOCKOUT
ACCESSOR WIRING
ENTR
7-3/4
5-7/8
EF-07
All dimensions are in inches. They are subject
to change without notice. Certified dimensions
will be provided upon request.

035-18547-001-A-0902
8Unitary Products Group
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 3 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 4 for typical field wiring.
CONTROL WIRING
Refer to Figure 3 for the location of the control wire
access opening through the front of the unit.
Route the necessary low voltage control wires from ter-
minal block 1TB of the unit control box through this
access opening to the indoor unit and to the room ther-
mostat. Refer to Figure 4 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.
*To determine the total circuit length, add the following distances:
1 - Outdoor Unit to Indoor Unit ...................... _________
2 - Indoor Unit to Thermostat......................... _________
3 - Thermostat to Indoor Unit......................... _________
4 - Indoor Unit to Outdoor Unit ...................... _________
Total Circuit Length.... _________
Both the manual and the auto changeover thermostats
have non-adjustable, voltage-type anticipators for both
cooling and heating.
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.
RECOMMENDED
WIRE SIZE MAXIMUM TOTAL CIRCUIT LENGTH - FT.*
#19 Solid
#18 Solid 130 170
#18 Stranded
#16 Stranded 180 270
#14 Stranded
#12 Stranded 455 730

035-18547-001-A-0902
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FIGURE 4 - TYPICAL FIELD WIRING
TYPICAL
NOTE: SEE PN# 036-13335-002
FOR APPLICABLE THERMOSTATS.
TABLE 3: ELECTRICAL DATA
Model
EF Compressor Outdoor Fan Motor Min. Circuit
Amps
Max.
Fuse
Size
Min. Wire
Size,1
AWG
Power
Supply RLA LRA Power Factor Power Supply Qty. FLA (Each
-07 25 200/230-3-60 25.6 190.0 0.94 @ 208V 208/230-1-60 2 3.03 38.1 60 8 0.84 @ 230V
46 460-3-60 12.8 95.0 0.86 460-1-60 2 1.6 19.2 30 10
1. Based on three, 50ºC insulated copper conductors in steel conduit.

035-18547-001-A-0902
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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 - small 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 5.
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 50 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.
Vertical Rise
(PSI/Ft.)
EF-07/FF-07 22.5 5/8 3.5 0.5