KRACK SLD Series Specification sheet

E207120
OPERATING
AND
INSTALLATION
MANUAL
INSTALLING
INSTRUCTIONS
SLD/DLD/PLD AIR COOLED CONDENSING UNITS
SLD SERIES COND. UNITS
R-22, R-404A/R-507
10-60 HP.
DLD SERIES COND. UNITS
R-22, R-404A/R-507
7-50 HP./CIRCUIT
PLD SERIES COND. UNITS
R-22, R-404A/R-507
14-100 HP.

PLD/DLD/PLD AIR COOLED CONDENSING UNITS
1
TABLE OF CONTENTS
I. Receipt of Equipment……………..3
II. Refrigeration Piping……………..3
III. System Evacuation………….…..5
IV. Electrical………………………...5
V. Charging the System..…………...5
VI. Operation Checkout…………....5
VII. Features and Controls………...6
VIII. Normal Maintenance…………7
TABLES:
Table 1 : Recommended
Line Sizes………………...8,9
Table 2 : Condensing Unit
Refrigerant Charge..10,11,12
Table 3 : Low Pressure
Control Settings………….13
Table 4 : Fan Cycling
Control Settings………….13

SLD/DLD/PLD AIR COOLED CONDENSING UNITS
2
I. RECEIPT OF EQUIPMENT
A) DAMAGE CHECK
P L I - 0700 H 2 M
Condensing Unit Family
S - Single Compressor
Voltage
P - Parallel Compressors K - 208/230/3/60
D - Dual Compressors M - 460/3/60
P - 575/3/60
Levitor Condenser U - 380/3/50
Compressor Manufacture Refrigerant
B - Bitzer Semi-Hermetic 2 - R22
C - Carlyle Semi-Hermetic 4 - R404A
D - Copeland Discus 7 - R507
I - Ingersoll-Rand Semi-Hermetic
V - Copeland Screw
Temperature
H - High
Total HP M - Medium
0100 = 10 HP w/standard comp L - Low
0101 = 10 HP w/oversized comp
0700 = (2) 35 HP w/standard comp
0701 = (2) 35 HP w/oversized comp
Large Condensing Unit Model Key

SLD/DLD/PLD AIR COOLED CONDENSING UNITS
3
All equipment should be carefully checked
for damage as soon as it is received. If any
damage is evident, a notation must be made
on the delivery receipt before it is signed
and claim should then be filed against the
freight carrier.
B) CHECK VOLTAGE
Carefully check nameplate voltage and
current characteristics to be sure unit is
compatible with power supply.
C) HANDLING
Never hoist the unit from any point
excepting the base lifting holes provided for
this purpose.
Lift with spreader and hooks as shown in
Figure 1. When moving unit by forklift, lift
from compressor end ONLY. Do not lift
from condenser end.
D) LEVELING AND BOLT DOWN
PROCEDURE
A solid level foundation should be provided
for the unit large enough to accommodate
the full length of the base rails. If the
mounting location is not sturdy and perfectly
level, place shims under low points before
tightening down with hold-down bolts.
Improper bolting-down procedure can
seriously warp the framework, particularly
with the large condenser fan units (3 fans or
more).
E) UNIT LOCATION
Large air-cooled condensing units dissipate
a tremendous amount of heat and require
large volumes of air. Short-circuiting of the
condenser air, or restricting the free entry of
air into the coil will result in reduced
capacity and highpower consumption. Take
care to reduce such negative operation
effects by providing for unrestricted free air
flow into and from the unit. At most, the
unit should not be positioned so as to have
no more than one of its sides positioned
close to a vertical building side or wall. At
that point, this should be a minimum of 3’
unit-to-wall free air clearance distance.
F) LOSS OF GAS HOLDING CHARGE
Each Condensing unit is evacuated to
remove moisture, leak tested, and then
shipped with a gas holding charge. Absence
of this charge may indicate a leak has
developed in transit. The system should not
be charged with refrigerant until it is
verified that there is no leak or the source of
the leak is located.
G) CHECK COMPRESSOR
The compressor is bolted to the base of the
condensing unit using solid mounting
techniques.
Check the compressor mounting bolts.
Tighten these bolts as much as possible to
prevent excess vibration. Check electrical
junction connections of the compressor;
tighten only those that may have come loose
during transit.
II. PIPING
1) REFRIGERATION PIPING
Use ACR grade copper tubing, or conform
otherwise to local and national codes.
Piping methods must meet these codes and
result in acceptable piping practice.
A) SUCTION LINE
Design and sizing of the suction line is
critical to maintain:
1) Proper refrigerant velocity

SLD/DLD/PLD AIR COOLED CONDENSING UNITS
4
2) Practical pressure drop (usually
equivalent to 2 F maximum)
3) For proper oil return, all horizontal lines
should be sloped downwards toward
compressor at 1 inch per 10 feet.
Suction line risers must be trapped at the
bottom of the rise and at every 20-foot
increment for proper oil return. The proper
balance is to design suction lines for
approximately 1,200 ft. per min. velocity in
risers and approximately 600 ft per min.
velocity in horizontal lines. “P” traps should
be installed at the bottom of all risers in
suction lines for proper oil return.
Table 1 lists common suction line sizing
which can be used with-but not instead of -
ASHRAE- guidelines.
Suction lines should not be exposed to heat
unless insulated. Insulation also prevents
sweating and subsequent damage to goods.
B) LIQUID LINE
Avoid excessive liquid line pressure drop by
using Table 1 and ASHRAE guidelines to
size the liquid line. Install a liquid line
solenoid valve at the evaporator.
On parallel compressor systems, if one
compressor cycles off due to part load
conditions, suction lines must be sized to
allow for oil return under reduced load
conditions.
2) LINE FABRICATION &
SOLDERING
Copper pipe should be cut with a wheel type
cutter and not with a hacksaw. Using a
hacksaw produces copper filings which can
cause problems if it gets into the system.
Also, if the pipes to be used are not capped
and perfectly clean, they should be cleaned
with a clean lint free rag before fabrication
into the system.
Soft solders should be avoided wherever
possible, as in most cases they require the
use of a flux. Most of the low temperature
solder flux consists of heavy wax type
materials which if allowed to enter the
system cause excessive service problems in
the form of wax at expansion valves which
looks like moisture but cannot be removed
by the average dryer core. Where silver
brazing must be used between copper and
brass or copper and steel joints, care should
be taken to avoid excessive use of flux lest it
be introduced into the system to create
problems at a later date. Easy-Flo or silver
solders which contain sufficient silver
content to still retain joint strength and yet
require minimum use of flux are
recommended here.
For copper to copper joints phos-copper
solders with 4 to 15% silver content are
recommended. No flux is required, and the
resultant joints are of maximum strength
without brittleness.
Nitrogen should be used to exclude the
oxygen within the pipes during soldering in
order to prevent the creation of large
quantities of copper oxide. Copper oxide is
a good abrasive and if it gets into the
compressor it can cause excessive wear
and/or shorting out of electric motor
windings.
3) LEAK TESTING
When all refrigeration connections have
been completed, the entire system must be
tested for leaks. With all valves in the
system open, pressurize the system to no
more than 175 PSIG with refrigerant and dry
nitrogen. The use of an electronic type leak
detector is highly recommended.
III. SYSTEM EVACUATION
CAUTION: DO NOT use the
compressor as a vacuum pump.
DO NOT start the
compressor while it is in vacuum.

SLD/DLD/PLD AIR COOLED CONDENSING UNITS
5
A two-stage vacuum pump is recommended
if moisture is to be removed by evacuation.
A single-stage pump will not remove
moisture. An electronic vacuum gauge
calibrated in microns is recommended for
recording vacuum. Connect the vacuum
meter to some point on the system, such as
the purge connection on the condenser, so
the actual vacuum is read rather than the
vacuum at the vacuum pump. The pump
should be connected to both the low and
high pressure sides with copper tube or high
vacuum hoses (1/2 inch I.D. minimum)
A vacuum of 500 microns and below is
recommended to effectively remove
moisture from the system. Close the valve
at the pump and watch the gauge. If the
system contains moisture or a leak is present
the vacuum gauge will show a rise in
pressure. When there is no visible rise in
system pressure for 12 hours after the
vacuum valve is shut off, evacuation is
complete.
IV. ELECTRICAL
The power supply voltage, phase and
frequency must match what is shown in the
condensing unit data plate. All wiring must
be carefully checked against the condensing
unit wiring diagram.
V. CHARGING THE SYSTEM
Weigh the refrigerant cylinder before
charging the system so an accurate record
can be made of the amount of refrigerant put
in the system.
Connect the suction service gauge to the
compressor suction service valve and the
discharge service gauge to the receiver
outlet port. The third hose from the
charging manifold should be connected to
the refrigerant cylinder.
CAUTION: NEVER charge liquid
refrigerant through the suction side of the
system.
When initially charging a system that is in a
vacuum, liquid refrigerant can be directly
added into the receiver until the system
pressure equalizes with pressure in the
refrigerant cylinder.
Start the system and finish charging until the
sight glass is clear.
Outdoor condensing units are furnished with
a condenser flooding type of head pressure
control valve for cold weather operation.
This valve should be set at 180 psig for
better performance for this unit. The correct
refrigerant charge must be added at start up.
Table 2 indicates the refrigerant charge at
different ambient temperature.
Determine the ambient temperature at the
time of charging the system and locate this
temperature at the top of table 2. Next
locate the condensing unit model number
and the refrigerant type on the left side of
the table. Read from left to right until you
reach the column for the days ambient
temperature. Record the condensing unit
charge at this set of conditions. Next locate
the column for the winter design
temperature and record the condensing unit
charge. The difference between these two
values is the additional refrigerant that must
be added to the system for proper winter
operation.
VI. OPERATION CHECKOUT
1) Check electrical connections, fan blade
set screws and refrigerant connections. Be
sure they are tight.
2) Check the low pressure control setting.
See Table 3 for proper setting.
3) With the system operating, check the
supply voltage. It must be within +/- 10%
of the voltage marked on the unit nameplate.
4) Check the room thermostat setting. Be
sure it functions properly.
5) Check the compressor amp draw. It must
not exceed the value on the unit data plate.
6) After the room temperature is reached,
the expansion valve superheat must be
checked. Too low suction superheat may

SLD/DLD/PLD AIR COOLED CONDENSING UNITS
6
cause liquid to return to the compressor.
Too high suction superheat may cause
excessive discharge temperatures. For
maximum system capacity the minimum
superheat must be 20 F and the maximum
superheat must be 30 F to 40 F at the
compressor for medium and low
temperature, respectively.
7) After several hours of operation, check
the compressor oil level. The oil level
should be 1/2 the way up on the glass with
the compressor off. Care must be taken to
be sure the proper lubricant is used.
8) On freezer system after the coil is frosted,
manually advance the defrost timer to
initiate a defrost. Observe the defrost cycle
to see if all controls are functioning properly
and that the coil is clear of all frost before
the system returns to refrigeration. Reset the
defrost timer to the correct time of day.
9) After the room has reached temperature
and the liquid line solenoid has closed,
check the compressor to be sure it has
pumped down and shut off. If the
compressor continues to run, check the low
pressure control setting as outlined in step
#2.
VII. FEATURES AND CONTROLS
1) REFRIGERANT OIL
The oil level should be 1/2 the way up on
the glass in the compressor with the
compressor off. Oil level should be checked
frequently during startup and during the first
48 hours of operating time. Since no
dependable rule of thumb can be used, the
only safe method is to carefully check the oil
level and add as little oil as needed. If oil is
required to be added, an oil pump is
recommended to pump the oil directly into
the compressor against suction pressure.
Refrigerant oil should be purchased in
sealed containers and should not be left open
to atmosphere. Exposure to air and moisture
for extended periods will result in
contamination of the oil and cause harmful
reactions in the compressor. Do not transfer
oil from one container to another.
2) HIGH AND LOW PRESSURE
CONTROLS
SLD/DLD/PLDs are furnished with
individual manual reset high-pressure and
low-pressure controls.
These are safety controls for the system.
(See Table 3).
3) OIL FAILURE SWITCH
Each compressor on the Model
SLD/PLD/DLD unit has its own electronic
oil pressure control. Should oil pump
differential pressure, measured between the
pump inlet and outlet, fall below 9 psig for a
period of two minutes, the control will open
and stop the compressor.
A trip of the oil pressure safety control is a
warning that the compressor has been
running without proper lubrication.
Repeated trips of the control are a clear
indication that something in the system
requires immediate attention and corrective
action.
If system is plagued with oil failure safety
switch tripouts, it is almost always traceable
to one of the following sources.
a) Shortage of oil in the compressor
b) Oil trapping in the system
c) Liquid slugback to the compressor for
some reason.
d) Compressor short cycling
e) Refrigerant in the oil on startup
f) Malfunctioning oil pump
g) Clogged on the oil suction screen
h) Excessively low suction pressure
i) Possibly a defective control, but not
probable
j) Low refrigerant charge in low ambient
conditions
4) CRANKCASE HEATERS
Crankcase heaters are provided to reduce the
possibility of refrigerant condensing in the
crankcase oil.

SLD/DLD/PLD AIR COOLED CONDENSING UNITS
7
NOTE: The use of a crankcase
heater installed on the compressor
does not always assure that liquid
refrigerant will not condense in the
oil under severe weather conditions.
If the compressor is subjected to extremely
low temperatures and the evaporator is in a
relatively warm location, the temperature at
the compressor may still drop below
evaporator temperature in which case liquid
refrigerant will condense in the oil.
5) ELECTRICAL POWER
Control voltage is 230/60/1 as standard.
All condensing units are factory tested for
operation before leaving the plant and
direction of rotation of all condenser fans
are checked to see that they are the same.
However, on installation, phase reversals
may cause the fans to run backward. It’s
obvious that this can only be corrected in the
field. On start-up, be sure to check that fan
rotation is according to arrow decal on or
near the fan blade. Air flow is up (vertical).
Reversing of any two wires of the power
supply to the condenser fan contactor will
change the direction of the fan rotation.
6) CONDENSER FAN CYCLING
Pressure switches are included to cycle all
but the first condenser fan(s) in response to
head pressure.
See Table 4 for suggested pressure settings
used on all multiple condenser fan systems.
7) LOW AMBIENT FLOODING
CONTROLS ARE STANDARD
Condenser Liquid Flooding utilizes a field-
adjustable (100 to 225 psig) condensate
holdback valve. Head pressure control
valve for this unit should be set at 180 psig.
8) PUMPDOWN & RESET SWITCH
With toggle switch down in the reset and
pumpdown position, the control circuit is
reset and the liquid line solenoid valve is
de-energized. This allows the compressor to
pumpdown on the low-pressure control.
With the toggle switch up in the run
position, the liquid solenoid valve is
energized and allows the system to cycle on
the room thermostat.
VIII. NORMAL MAINTENANCE
1) Check compressor oil sight glass for
proper level and check visible piping for
oil spots, which may indicate a
refrigerant leak.
2) Check liquid refrigerant sight glass for
proper charge. If refrigerant must be
added, use charging procedure outline in
section V.
3) Check inlet air side of condenser;
surface should be free of foreign matter.
TABLE 1A
RECOMMENDED LINE SIZES FOR R-22
SUCTION LINE SIZE
SUCTION TEMPERATURE

SLD/DLD/PLD AIR COOLED CONDENSING UNITS
8
SYSTEM
CAPACITY
BTU/H
+20° F
Equivalent Suction Line Length
-20° F
Equivalent Suction Line Length
Liquid Line
Receiver to Expansion Valve
25'
50'
75'
100'
25'
50'
75'
100'
25'
50'
75'
100'
R-22
36,000
7/8
1 1/8
1 1/8
1 3/8
1 1/8
1 3/8
1 3/8
1 3/8
3/8
1/2
1/2
1/2
42,000
7/8
1 1/8
1 1/8
1 1/8
1 1/8
1 3/8
1 3/8
1 5/8
3/8
1/2
1/2
1/2
48,000
7/8
1 1/8
1 1/8
1 1/8
1 1/8
1 3/8
1 3/8
1 5/8
1/2
1/2
1/2
1/2
54,000
1 1/8
1 1/8
1 1/8
1 3/8
1 3/8
1 3/8
1 5/8
1 5/8
1/2
1/2
1/2
1/2
60,000
1 1/8
1 1/8
1 1/8
1 3/8
1 3/8
1 3/8
1 5/8
1 5/8
1/2
1/2
1/2
1/2
66,000
1 1/8
1 1/8
1 3/8
1 3/8
1 3/8
1 5/8
1 5/8
1 5/8
1/2
1/2
5/8
5/8
72,000
1 1/8
1 3/8
1 3/8
1 3/8
1 3/8
1 5/8
1 5/8
2 1/8
1/2
1/2
5/8
5/8
78,000
1 1/8
1 3/8
1 3/8
1 3/8
1 3/8
1 5/8
1 5/8
2 1/8
1/2
1/2
5/8
5/8
84,000
1 1/8
1 3/8
1 3/8
1 3/8
1 3/8
1 5/8
2 1/8
2 1/8
1/2
5/8
5/8
5/8
90,000
1 1/8
1 3/8
1 3/8
1 5/8
1 3/8
1 5/8
2 1/8
2 1/8
1/2
5/8
5/8
5/8
120,000
1 3/8
1 3/8
1 5/8
1 5/8
1 5/8
2 1/8
2 1/8
2 1/8
5/8
5/8
5/8
7/8
150,000
1 3/8
1 5/8
1 5/8
2 1/8
2 1/8
2 1/8
2 1/8
2 5/8
5/8
7/8
7/8
7/8
180,000
1 3/8
1 5/8
1 5/8
2 1/8
2 1/8
2 1/8
2 5/8
2 5/8
5/8
7/8
7/8
7/8
210,000
1 5/8
2 1/8
2 1/8
2 1/8
2 1/8
2 5/8
2 5/8
2 5/8
5/8
7/8
7/8
7/8
240,000
1 5/8
2 1/8
2 1/8
2 1/8
2 1/8
2 5/8
2 5/8
2 5/8
5/8
7/8
7/8
7/8
300,000
2 1/8
2 1/8
2 1/8
2 5/8
2 1/8
2 5/8
3 1/8
3 1/8
7/8
7/8
1 1/8
1 1/8
360,000
2 1/8
2 1/8
2 5/8
2 5/8
2 5/8
2 5/8
3 1/8
3 1/8
7/8
7/8
1 1/8
1 1/8
480,000
2 1/8
2 5/8
2 5/8
2 5/8
7/8
1 1/8
1 1/8
1 1/8
600,000
2 1/8
2 5/8
3 1/8
3 1/8
7/8
1 1/8
1 1/8
1 3/8
720,000
2 5/8
3 1/8
3 1/8
3 1/8
7/8
1 1/8
1 1/8
l 3/8
840,000
2 5/8
3 1/8
3 1/8
3 5/8
1 1/8
1 1/8
1 3/8
1 3/8
960,000
2 5/8
3 1/8
3 1/8
3 5/8
1 1/8
1 3/8
1 3/8
1 3/8
Line sizes which are shaded indicate the maximum suction line size which may be used for a riser. In no case should the riser
exceed the horizontal line size. Properly placed suction traps must be used to insure proper oil return.
TABLE 1B
RECOMMENDED LINE SIZES FOR R-404A and R-507
SUCTION LINE SIZE

SLD/DLD/PLD AIR COOLED CONDENSING UNITS
9
SYSTEM
CAPACITY
BTU/H
SUCTION TEMPERATURE
+20° F
Equivalent Suction Line Length
-20° F
Equivalent Suction Line Length
Liquid Line
Receiver to Expansion Valve
25'
50'
75'
100'
25'
50'
75'
100'
25'
50'
75'
100'
R-404A and R-507
36,000
7/8
1 1/8
1 1/8
1 1/8
1 1/8
1 1/8
1 3/8
1 3/8
1/2
1/2
1/2
1/2
42,000
1 1/8
1 1/8
1 1/8
1 3/8
1 1/8
1 3/8
1 3/8
1 5/8
1/2
1/2
1/2
1/2
48,000
1 1/8
1 1/8
1 3/8
1 3/8
1 1/8
1 3/8
1 3/8
1 5/8
1/2
1/2
1/2
5/8
54,000
1 1/8
1 1/8
1 3/8
1 3/8
1 3/8
1 3/8
1 5/8
1 5/8
1/2
1/2
1/2
5/8
60,000
1 1/8
1 1/8
1 3/8
1 3/8
1 3/8
1 3/8
1 5/8
1 5/8
1/2
1/2
5/8
5/8
66,000
1 1/8
1 3/8
1 3/8
1 3/8
1 3/8
1 5/8
1 5/8
1 5/8
1/2
1/2
5/8
5/8
72,000
1 1/8
1 3/8
1 3/8
1 5/8
1 3/8
1 5/8
1 5/8
1 5/8
1/2
5/8
5/8
5/8
78,000
1 1/8
1 3/8
1 3/8
1 5/8
1 5/8
1 5/8
1 5/8
1 5/8
5/8
5/8
5/8
5/8
84,000
1 1/8
1 3/8
1 5/8
1 5/8
1 5/8
1 5/8
1 5/8
2 1/8
5/8
5/8
5/8
5/8
90,000
1 3/8
1 3/8
1 5/8
1 5/8
1 5/8
1 5/8
2 1/8
2 1/8
5/8
5/8
5/8
7/8
120,000
1 3/8
1 5/8
1 5/8
2 1/8
1 5/8
2 1/8
2 1/8
2 1/8
5/8
5/8
7/8
7/8
150,000
1 5/8
1 5/8
2 1/8
2 1/8
2 1/8
2 1/8
2 1/8
2 5/8
5/8
7/8
7/8
7/8
180,000
1 5/8
2 1/8
2 1/8
2 1/8
2 1/8
2 1/8
2 5/8
2 5/8
7/8
7/8
7/8
7/8
210,000
1 5/8
2 1/8
2 1/8
2 1/8
2 1/8
2 5/8
2 5/8
2 5/8
7/8
7/8
7/8
7/8
240,000
1 5/8
2 1/8
2 1/8
2 1/8
2 1/8
2 5/8
2 5/8
2 5/8
7/8
7/8
1 1/8
1 1/8
300,000
2 1/8
2 1/8
2 5/8
2 5/8
2 5/8
2 5/8
2 5/8
3 1/8
7/8
1 1/8
1 1/8
1 1/8
360,000
2 1/8
2 1/8
2 5/8
2 5/8
1 1/8
1 1/8
1 1/8
1 3/8
480,000
2 1/8
2 5/8
2 5/8
3 1/8
1 1/8
1 1/8
1 3/8
1 3/8
600,000
2 5/8
2 5/8
3 1/8
3 1/8
1 1/8
1 3/8
1 3/8
1 5/8
Line sizes which are shaded indicate the maximum suction line size which may be used for a riser. In no case should the riser
exceed the horizontal line size. Properly placed suction traps must be used to insure proper oil return.