DISCHARGETEMPSUCTIONDISCHARGEAMPSLOCKEDCHARGE INCHARGE IN
AIRDROP °FROTOR AMPSOUNCESFLUID OZ.
SH14J30B-A
SH14J30B-A
SH20J30B-A
SH20J30B-A
* Rating Conditions: 80° F. Room Air Temperature and 59% Relative Humidity with 95° F. Outside Air Temperature at 40% Relative Humidity.
56.7823.22792967.8432832
8.5
52.8327.1679.52829.8523932
10.4
3
COMPONENT OPERATION AND TESTING
WARNING
COMPRESSOR WINDING TEST
(See Figure 2.)
DISCONNECT ELECTRICAL POWER TO
THE UNIT BEFORE SERVICING OR
TESTING
COMPRESSORS
Compressors are single phase, 208/230 volt. All
compressor motors are permanent split capacitor
type, using only a running capacitor across the
start and run terminal.
All compressors are internally spring mounted and
externally mounted on rubber isolators.
Line Voltage Overload
The compressor is equipped with an internal line
voltage overload. This overload is embedded in
the windings of the motor to sense the motor
temperature. The overload will open and
disconnect the power to the motor due to high
temperatures caused by:
Remove the compressor terminal box cover and
disconnect the wires from the terminals. Using
an ohmmeter, check continuity across the
following:
FIGURE 2 COMPRESSOR WINDING TEST
Testing Procedures
1.Terminal "C" and "S" - no continuity open winding - replace compressor.
2.Terminal "C" and "R" - no continuity open winding - replace compressor.
1.A locked rotor.
2.Excessive running amps.
3.High discharge temperature.
4.Low refrigerant charge.
FIGURE 1 INTERNAL OVERLOAD
LINE BREAK
INTERNAL OVERLOAD
OHMMETER
4
3.Terminal "R" and "S" - no continuity
open winding - replace compressor.
4.Terminal "C" and the shell of the
compressor – continuity – grounded
motor – replace compressor.
5. Should continuity exist between
terminals "R" and "S", but not between
terminals "C" and "S" and "C" and "R",
the internal overload may be open. If
the compressor is extremely hot, allow
it sufficient time to cool. It may require
as long as one hour for the compressor
to cool sufficiently for the internal
overload to close.
GROUND TEST
FAN MOTOR (Figure 4)
Use an ohmmeter set on its highest scale. Touch
one lead to the compressor body (clean point of
contact, as a good connection is a must) and the
other probe in turn to each compressor terminal.
(See Figure 3.) If a reading is obtained, the
compressor is grounded and must be replaced.
FIGURE 3 TYPICAL GROUND TEST
CHECKING COMPRESSOR EFFICIENCY
The reason for compressor inefficiency is
normally due to broken or damaged suction
and/or discharge valves, reducing the ability of
the compressor to pump refrigerant gas.
This condition can be checked as
follows:
1. Install a piercing valve on the suction and
discharge or liquid process tube.
A 230 volt single phase permanent split capacitor
motor is used to drive the evaporator blower and
condenser fan. A running capacitor is wired
across the start and run terminals of the motor.
The motor is totally enclosed and is protected with
a line voltage overload located internally of the
motor. The motor shaft is stainless steel to resist
corrosion.
FIGURE 4 FAN MOTOR
FAN MOTOR – TEST
Disconnect power to the unit.
1. Determine that the capacitor is serviceable.
2. Disconnect the black lead from the circuit
board.
3. Apply "live" test cord leads to the common
terminal of the capacitor and the black lead.
The motor should run at high speed.
2. Attach gages to the high and low sides of the
system.
3. Start the system and run a "cooling or
heating performance test."
If test shows:
A. Below normal high side pressure.
B. Above normal low side pressure.
C. Low temperature difference across the coil.
The compressor valves are faulty replace the compressor.
5
SYSTEM CONTROL SWITCH
(Figure 5)
This switch is double pole, single throw. Check
for continuity between terminals 2 and 3, and 5
and 6.
CAPACITOR – TEST
1. Remove the capacitor from the unit.
2. Check for visual damage such as bulges,
cracks, or leaks.
FIGURE 5 SWITCH, ON-OFF
CAPACITOR, RUN
A run capacitor is wired across the auxiliary and
main winding of a single phase permanent split
capacitor motor such as the compressor and fan
motors. A single capacitor can be used for each
motor or a dual rated capacitor can be used for
both.
The capacitor’s primary function is to reduce the
line current while greatly improving the torque
characteristics of a motor. The capacitor also
reduces the line current to the motor by improving
the power factor of the load. The line side of the
capacitor is marked with a red dot and is wired to
the line side of the circuit. (See Figure 6.)
FIGURE 6 RUN CAPACITOR HOOK–UP
COMPRESSOR
FA N
MOTOR
3. For dual rated capacitors, apply an ohmmeter
lead to the common (C) terminal and the other
probe to the compressor (HERM) terminal.
A satisfactory capacitor will cause a deflection
on the pointer, then gradually move back to
infinity.
4. Reverse the leads of the probe and
momentarily touch the capacitor terminals.
The deflection of the pointer should be two
times that of the first check if the capacitor is
good.
5. Repeat steps 3 and 4 to check the fan motor
capacitor.
NOTE: A shorted capacitor will indicate a low
resistance and the pointer will move more
to the “0” end of the scale and remain there
as long as the probes are connected. An
open capacitor will show no movement of
the pointer when placed across the terminals
of the capacitor.
THERMOSTAT
A cross ambient
thermostat is used
to maintain the desired
comfort level. The
thermostat reacts only to
a change in temperature
at the bulb location.
Important to the
successful operation
of the unit is the position
of the sensing bulb in
relation to the evaporator.
FIGURE 7
SENSING BULB
LOCATION
See Figure 7.
RED DOT
Thermostat
(Part No. 618-225-02)
RANGE:
RUN CAPACITOR
6
60° F ( ± 2° ) to 90° F( ± 4° )
TEST
Remove the wires from the thermostat. Turn the
thermostat to its coldest position. Check to see
if there is continuity between the two terminals.
Turn the thermostat to its warmest position.
Check continuity to see if the thermostat contacts
open.
(More Follows)
Note: The temperature must be within the
range listed to check the thermostat. Refer to
the troubleshooting section in this manual for
additional information on thermostat testing.
7
LOW AMBIENT BY–PASS VALVE
The HazardGard unit is designed to operate at
low outside ambient temperatures. This is
accomplished by the use of a bypass valve
installed in the refrigeration circuit. The valve is
connected between the discharge line at the
compressor and the suction process tube. The
valve responds to suction pressure which, when
reduced in the system, causes the valve to open
and bypass hot gas from the high pressure side
to the low pressure side of the system. The hot
gas entering the compressor mixes with the cool
gas returned through the suction line, thus
increasing the suction pressure. The valve is
preset to open when the suction pressure reaches
50 psig. This pressure setting cannot be altered.
The system can be operated at outdoor
temperatures as low as 45°
F before the
evaporator coil will begin to accumulate frost.
To determine if the valve operates, block the return
air to the evaporator coil. Turn on the unit and
touch the tube at the bypass valve outlet which
connects to the suction process tube. When the
low side pressure reaches approximately 50 psig,
the valve will begin to open and the tube will get
hot. This method will determine if the valve is
responding to the suction pressure change.
SEALED REFRIGERATION SYSTEM
REPAIRS
EQUIPMENT REQUIRED
1. Voltmeter
2. Ammeter
3. Ohmmeter
4. E.P.A Approved Refrigerant Recovery System
5. Vacuum Pump (capable of 200 microns or
less vacuum).
6. Acetylene Welder
7. Electronic Halogen Leak Detector G.E. Type
H-6 or equivalent).
8. Accurate refrigerant charge measuring device
such as:
a. Balance Scales - 1/2 oz. accuracy
b. Charging Board - 1/2 oz. accuracy
9. High Pressure Gauge - (0-400 lbs.)
10. Low Pressure Gauge - (30" - 150 lbs.)
11. Vacuum Gauge - (0-1000 microns)
EQUIPMENT MUST BE CAPABLE OF:
1. Recovering CFC’s as low as 5%.
2. Evacuation from both the high side and low
side of the system simultaneously.
3. Introducing refrigerant charge into the high
side of the system.
4. Accurately weighing the refrigerant charge
actually introduced into the system.
FIGURE 8
LOW AMBIENT Bypass VALVE
5. Facilities for flowing nitrogen through the
refrigeration tubing during all brazing
processes.
8
HERMETIC COMPONENT REPLACEMENT
The following procedure applies when replacing
components in the sealed refrigeration circuit or
repairing refrigerant leaks. (Compressor,
condenser, evaporator, capillary tube, refrigerant
leaks, etc.)
1. Recover the refrigerant from the system at the
process tube located on the high side of the
system by installing a line tap on the process
tube. Apply the gauge from the process tube
to EPA approved gauges from the process
tube to the EPA approved recovery system.
Recover the CFC’s in the system to at least
5%.
2. Cut the process tube below the pinch off in
the suction side of the compressor.
10.Evacuate the system to an absolute holding
pressure of 200 microns or less.
NOTE: This procedure can be speeded up by
the use of heat lamps, or by breaking the
vacuum with refrigerant or dry nitrogen at
5,000 microns. Pressure system to 5 PSIG
and leave in the system a minimum of 10
minutes. Recover refrigerant, and proceed
with evacuation to a pressure of 200 microns
or a minimum of 10%.
11. Break the vacuum by charging the system
from the high side with the correct amount of
refrigerant specified. This will prevent boiling
the oil out of the crankcase.
NOTE: If the entire charge will not enter the
high side, allow the remainder to enter the
low side in small increments while operating
the unit.
3. Connect the line from the nitrogen tank to the
suction process tube.
4. Drift dry nitrogen through the system and
unsolder the more distant connection first.
(Filter drier, high side process tube, etc.)
5. Replace the inoperative component, and
always install a new filter drier. Drift dry
nitrogen through the system when making
these connections.
6. Pressurize the system to 30 PSIG with proper
refrigerant and boost the refrigerant pressure
to 150 PSIG with dry nitrogen.
7. Leak test the complete system with the electric
halogen leak detector, correcting any leaks
found.
8. Reduce the system to zero gauge pressure.
12.Restart the unit several times after allowing
pressures to stabilize. Pinch off the process
tubes, cut and solder the ends. Remove the
pinch off tool, and leak check the process tube
ends.
SPECIAL PROCEDURES IN THE CASE OF
COMPRESSOR MOTOR BURNOUT
1. Recover all refrigerant and oil from the system.
2. Remove the compressor, capillary tube and
filter drier from the system.
3. Flush the evaporator, condenser and all
connecting tubing with dry nitrogen, or
equivalent, to remove all contamination from
the system. Inspect the suction and discharge
lines for carbon deposits. Remove and clean
if necessary.
4. Reassemble the system, including a new drierstrainer and capillary tube.
9. Connect the vacuum pump to the high side
and low side of the system with deep vacuum
hoses, or copper tubing. (Do not use regular
hoses.)
5. Proceed with processing as outlined under
hermetic component replacement.
9
ROTARY COMPRESSOR SPECIAL
TROUBLESHOOTING AND SERVICE
Basically, troubleshooting and servicing rotary
compressors is the same as on the
reciprocating compressor with only a few
exceptions.
1. Because of the spinning motion of the rotary,
the mounts are critical. If vibration is present,
check the mounts carefully.
REFRIGERANT CHARGE
1. The refrigerant charge is extremely critical.
Measure the charge carefully and as exactly
as possible to the nameplate charge.
2. The correct method for charging the rotary is
to introduce liquid refrigerant into the high side
of the system with the unit off. Then start the
compressor and enter the balance of the
charge, gas only, into the low side.
2. The electrical terminals on the rotary are in a
different order than the reciprocating
compressors. The terminal markings are on
the cover gasket. Use your wiring diagram to
insure the correct connections.
All inoperative compressors returned to
Friedrich must have all lines properly plugged
with the plugs from the replacement
compressor.
The introduction of liquid into the low side,
without the use of a capillary tube, will cause
damage to the discharge valve of the rotary
compressor.
NOTE:
10
TROUBLESHOOTING
PROBLEMPOSSIBLE CAUSETO CORRECT
Power disconnected.
System switch in “Off” position.
Unit does not
run.
PROBLEMPOSSIBLE CAUSETO CORRECT
Branch circuit fuse blown or
circuit breaker tripped.
Inoperative system switch.
Loose or disconnected wiring at
switch.
Inoperative switch (On-Off).
Check power source.
Set switch correctly.
Replace fuse, reset breaker. If repeats, check fuse or breaker
size. Check for shorts in unit wiring and components.
Test for continuity.
Check wiring and connections. Connect per wiring diagram.
Test for continuity, 3 and 2, 5 and 6.
Dirty Filter.
Restricted air flow.
Inoperative thermostat.
Evaporator
coil freezes
up.
PROBLEMPOSSIBLE CAUSETO CORRECT
Compressor
runs
continually.
Does not
cycle off.
PROBLEMPOSSIBLE CAUSETO CORRECT
Short of refrigerant.
Partially restricted capillary.
Inoperative fan motor.
Excessive heat load.
Restriction in line.
Refrigerant leak.
Thermostat contacts stuck.
Clean as recommended in Owner’s Manual.
Check for dirty or obstructed coil - clean as required.
Test for shorted thermostat or stuck contacts.
Deice coil and check for leak.
Deice coil. Check temperature differential across coil. Touch
test coil return bends for same temperature. Test for low
running current.
Test and replace if inoperative.
Test cooling performance of unit. Unit undersized.
Check for partially iced coil. Check temperature split across
coil.
Check for presence of oil on silver soldered connections.
Check for partially iced coil. Check split across coil. Check
for low running amperage.
Check operation of thermostat. Replace if contacts remain
closed.
Loss of charge in thermostat bulb.
Thermostat
does not turn
unit on.
PROBLEMPOSSIBLE CAUSETO CORRECT
Thermostat
does not
turn unit off.
Loose or broken parts in
thermostat.
Incorrect wiring.
System switch open.
Thermostat set at coldest point
Thermostat contacts stuck.
Switch (On - Off) shorted.
Place jumper across thermostat terminals. If unit operates,
replace thermostat.
Check as above.
Connect per wiring diagram.
Test for continuity at switch terminals 2 and 3.
Turn to highest temperature setting to see of unit will cycle off.
Disconnect power to the unit. Remove cover of thermostat
and check if contact is stuck, if so replace thermostat.
Test switch for open contacts at terminals 2 and 3 with switch
in “Off” position.
11
TROUBLESHOOTING (Continued)
PROBLEMPOSSIBLE CAUSETO CORRECT
Compressor attempts to start
Compressor
attempts to
start, or runs
for short
periods only.
Cycles on
overload.
PROBLEMPOSSIBLE CAUSETO CORRECT
Compressor
does not
start - fan
motor
runs.
before system pressures are
equalized.
Low or fluctuating voltage.
Incorrect wiring.
Shorted or incorrect capacitor.
Restricted or low air flow through
condenser coil.
Compressor running abnormally
hot.
Overload opens too soon.
Thermostat contacts not closing.
Low voltage supply.
Switch (On-Off) inoperative.
Open capacitor.
Internal overload open.
Open or shorted compressor
windings
Allow a minimum of two (2) minutes to allow pressures to
equalize before attempting to start.
Check voltage with unit operating. Check for other appliances
on the circuit. Unit should be on separate circuit for proper
voltage, and be fused separately.
Connect per wiring diagram.
Check by substituting a known good capacitor of correct rating.
Check for proper fan speed or blocked condenser.
Check for kinked discharge line or restricted condenser. Check
amperage.
Change compressor if all other corrections above are normal.
Check continuity of thermostat at coldest setting. Jump
contacts, if compressor runs, replace thermostat.
Check for nameplate voltage.
Test for continuity.
Check by substituting a known good capacitor of correct rating.
Check voltage at compressor terminals. If voltage is satisfactory,
replace compressor.
Check windings for continuity and resistance. Direct test
compressor. If direct test fails, replace compressor.
PROBLEMPOSSIBLE CAUSETO CORRECT
Thermostat open or inoperative.
Does not
cool, or
cools only
slightly
PROBLEMPOSSIBLE CAUSETO CORRECT
Fan motor
does not
run.
Dirty air filter.
Dirty or plugged condenser or
evaporator coil.
Poor air circulation in area being
cooled.
Low capacity - undercharge.
Compressor not pumping
properly.
Defective switch (On-Off).
Fan capacitor open.
Inoperative fan motor.
Incorrect wiring of fan circuit.
Relay open.
Check for seized motor bearings.
Bound fan blade or blower wheel.
Set to coldest position. Test thermostat and replace if
necessary.
Clean as recommended in Owner’s Manual.
Use steam or detergents to clean.
Adjust air louvers.
Clean, check for leak and make repair.
Check amperage draw against nameplate. If not conclusive,
make pressure test.
Check continuity across terminals 2 and 3.
Check by substituting a known good capacitor of the same
rating.
Direct test fan motor.
Connect per wiring diagram.
Replace Relay.
Rotate by hand, add oil, if noisy, replace.
Adjust for proper clearance.
Evaporator drain pan
overflowing.
Condensation forming on
bottom of base pan.
Water dripping from discharge
air grilles.
Evaporator drain pan cracked or
obstructed.
Water in center section of base
pan (compressor area).
Dirty Condenser coil.
Fan blade and slinger ring
improperly positioned.
Refer to Installation Instructions for proper installation.
Adjust motor mount to attain proper fan blade and blower
wheel clearance.
Check for deteriorated compressor grommets, or missing
mounting parts.
Adjust and tighten as required.
Clean obstructed drain trough.
Evaporator drain pan broken or cracked. Reseal or replace.
Dirty evaporator coil, or extremely high humidity conditions.
Clean coil with steam or detergent.
Repair and clean, or replace as required.
Remove condenser shroud, Clean and remove old sealer from
base pan and shroud. Apply new sealer, reinstall and check.
Clean with steam or detergent.
Adjust fan blade to 1/2" clearance from condenser coil.
13
WIRING DIAGRAM FOR SH14J30B-A & SH20J30B-A
14
HazardGard Cabinet Parts
15
HazardGard Chassis Parts
16
HAZARDGARD PARTS LIST
REF.PART NO.DESCRIPTIONAPPLICATION
SS
HH
12
40
JJ
33
ELECTRICAL PARTS
1611-935-49Compressor, Tecumseh, 230/208V; 60 Hz 1 Ph, Model AWG5515EXN ......................11