International comfort products RGS Series Installation and user guide

1
TABLE OF CONTENTS
SAFETY CONSIDERATIONS 2...................
UNIT ARRANGEMENT AND ACCESS 3...........
SUPPLY FAN (BLOWER) SECTION 5.............
COOLING 6....................................
R−410A REFRIGERANT 8.......................
COOLING CHARGING CHARTS 10...............
CONVENIENCE OUTLETS 14....................
SMOKE DETECTORS 16........................
SENSOR AND CONTROLLER 16.................
INDICATORS 21................................
TROUBLESHOOTING 21........................
PROTECTIVE DEVICES 22......................
GAS HEATING SYSTEM 23......................
ECONOMIZER SYSTEMS 33....................
WIRING DIAGRAMS 42.........................
PRE START−UP 44.............................
START−UP, GENERAL 44.......................
OPERATING SEQUENCES 46...................
FASTENER TORQUE VALUES 47................
APPENDIX I. MODEL NUMBER SIGNIFICANCE 48
APPENDIX II. PHYSICAL DATA 49...............
APPENDIX III. FAN PERFORMANCE 51..........
APPENDIX IV. ELECTRICAL DATA 55............
APPENDIX V. MOTORMASTER SENSOR
LOCATIONS 57.................................
UNIT START-UP CHECKLIST 58.................
RGS Series
7.5 to 12.5 Ton
Package Gas/Electric Cooling Units
With R−410A Refrigerant
And Micro−channel Condenser Coils
Service and Maintenance Instructions
509 08 3601 00
06/14/10

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SAFETY CONSIDERATIONS
Installation and servicing of air-conditioning
equipment can be hazardous due to system pressure
and electrical components. Only trained and qualified
service personnel should install, repair, or service
air-conditioning equipment. Untrained personnel can
perform the basic maintenance functions of replacing
filters. Trained service personnel should perform all
other operations.
When working on air-conditioning equipment, observe
precautions in the literature, tags and labels attached
to the unit, and other safety precautions that may
apply. Follow all safety codes. Wear safety glasses
and work gloves. Use quenching cloth for unbrazing
operations. Have fire extinguishers available for all
brazing operations.
Follow all safety codes. Wear safety glasses and
work gloves. Use quenching cloth for brazing
operations. Have fire extinguisher available. Read
these instructions thoroughly and follow all warnings
or cautions attached to the unit. Consult local building
codes and National Electrical Code (NEC) for special
requirements.
Recognize safety information. This is the safety−alert
symbol . When you see this symbol on the unit
and in instructions or manuals, be alert to the
potential for personal injury.
Understand the signal words DANGER, WARNING,
and CAUTION. These words are used with the
safety−alert symbol. DANGER identifies the most
serious hazards which will result in severe personal
injury or death. WARNING signifies a hazard which
could result in personal injury or death. CAUTION is
used to identify unsafe practices which may result in
minor personal injury or product and property
damage. NOTE is used to highlight suggestions
which will result in enhanced installation, reliability, or
operation.
FIRE, EXPLOSION HAZARD
Failure to follow this warning could result in
personal injury, death and/or property damage.
Refer to the User’s Information Manual provided
with this unit for more details.
Do not store or use gasoline or other flammable
vapors and liquids in the vicinity of this or any
other appliance.
What to do if you smell gas:
DO NOT try to light any appliance.
DO NOT touch any electrical switch, or use any
phone in your building.
IMMEDIATELY call your gas supplier from a
neighbor’s phone. Follow the gas supplier’s
instructions.
If you cannot reach your gas supplier, call the
fire department.
!WARNING
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in
personal injury or death.
Before performing service or maintenance
operations on unit, turn off main power switch to
unit. Electrical shock and rotating equipment could
cause injury.
!WARNING
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in
personal injury or death.
Units with convenience outlet circuits may use
multiple disconnects. Check convenience outlet
for power status before opening unit for service.
Locate its disconnect switch, if appropriate, and
open it. Tag−out this switch, if necessary.
!WARNING
UNIT OPERATION AND SAFETY HAZARD
Failure to follow this warning could cause personal
injury, death and/or equipment damage. R−410A
refrigerant systems operate at higher pressures
than standard R−22 systems. Do not use R−22
service equipment or components on refrigerant
equipment.
!WARNING

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509 08 3601 00
FIRE, EXPLOSION HAZARD
Failure to follow this warning could result in
personal injury or death.
Disconnect gas piping from unit when pressure
testing at pressure greater than 0.5 psig.
Pressures greater than 0.5 psig will cause gas
valve damage resulting in hazardous condition. If
gas valve is subjected to pressure greater than
0.5 psig, it must be replaced before use. When
pressure testing field-supplied gas piping at
pressures of 0.5 psig or less, a unit connected to
such piping must be isolated by closing the
manual gas valve(s).
!WARNING
CUT HAZARD
Failure to follow this caution may result in
personal injury.
Sheet metal parts may have sharp edges or
burrs. Use care and wear appropriate protective
clothing, safety glasses and gloves when handling
parts and servicing air conditioning units.
CAUTION
!
UNIT ARRANGEMENT AND ACCESS
General
Fig.1 and Fig.2 show general unit arrangement and
access locations.
FILTER ACCESS PANEL
INDOOR COIL ACCESS PANEL
Fig.1 −Typical Access Panel Locations (Back)
BLOWER
ACCESS
PANEL
FLUE OPENING
CONTROL BOX
COMPRESSOR
Fig.2−Typical Access Panel Location (Front)
Routine Maintenance
These items should be part of a routine maintenance
program, to be checked every month or two, until a
specific schedule for each can be identified for this
installation:
Quarterly Inspection (and 30 days after initial
start)
Return air filter replacement
Outdoor hood inlet filters cleaned
Belt tension checked
Belt condition checked
Pulley alignment checked
Fan shaft bearing locking collar tightness checked
Condenser coil cleanliness checked
Condensate drain checked
Seasonal Maintenance
These items should be checked at the beginning of
each season (or more often if local conditions and
usage patterns dictate):
Air Conditioning
Condenser fan motor mounting bolts tightness
Compressor mounting bolts
Condenser fan blade positioning
Control box cleanliness and wiring condition
Wire terminal tightness
Refrigerant charge level
Evaporator coil cleaning
Evaporator blower motor amperage

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509 08 3601 00
Heating
Heat exchanger flue passageways cleanliness
Gas burner condition
Gas manifold pressure
Heating temperature rise
Economizer or Outside Air Damper
Inlet filters condition
Check damper travel (economizer)
Check gear and dampers for debris and dirt
Air Filters and Screens
Each unit is equipped with return air filters. If the unit
has an economizer, it will also have an outside air
screen. If a manual outside air damper is added, an
inlet air screen will also be present.
Each of these filters and screens will need to be
periodically replaced or cleaned.
Return Air Filters
Return air filters are disposable fiberglass media type.
Access to the filters is through the small lift−out panel
located on the rear side of the unit, above the
evaporator/return air access panel. (See Fig.3.)
To remove the filters:
1. Grasp the bottom flange of the upper panel.
2. Lift up and swing the bottom out until the panel
disengages and pulls out.
3. Reach inside and extract the filters from the filter
rack.
4. Replace these filters as required with similar re-
placement filters of same size.
To re−install the access panel:
1. Slide the top of the panel up under the unit top
panel.
2. Slide the bottom into the side channels.
3. Push the bottom flange down until it contacts the
top of the lower panel (or economizer top).
IMPORTANT: DO NOT OPERATE THE UNIT
WITHOUT THESE FILTERS!
Outside Air Hood
Outside air hood inlet screens are permanent
aluminum−mesh type filters. Check these for
cleanliness. Remove the screens when cleaning is
required. Clean by washing with hot low−pressure
water and soft detergent and replace all screens
before restarting the unit. Observe the flow direction
arrows on the side of each filter frame.
Economizer Inlet Air Screen
This air screen is retained by spring clips under the
top edge of the hood. (See Fig.3.)
22 3/8 (569 mm)
HOOD
DIVIDER
OUTSIDE
AIR
CLEANABLE
ALUMINUM
FILTER
BAROMETRIC
RELIEF FILTER
CAP
FILTER
Fig. 3 −Filter Installation
To remove the filter, open the spring clips. Re−install
the filter by placing the frame in its track, then closing
the spring clips.
Manual Outside Air Hood Screen
This inlet screen is secured by a retainer angle
across the top edge of the hood. (See Fig.4.)
Fig. 4 −Screens Installed on Outdoor−Air Hood
(Sizes 7-1/2 to 12-1/2 Tons Shown)
To remove the screen, loosen the screws in the top
retainer and slip the retainer up until the filter can be
removed. Re-install by placing the frame in its track,
rotating the retainer back down and tighten all
screws.

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509 08 3601 00
SUPPLY FAN (BLOWER) SECTION
ELECTRICAL SHOCK HAZARD
Failure to follow this warning could cause personal
injury or death.
Before performing service or maintenance
operations on the fan system, shut off all unit
power and tag−out the unit disconnect switch. Do
not reach into the fan section with power still
applied to unit.
!WARNING
Supply Fan (Belt−Drive)
The supply fan system consists of a forward−curved
centrifugal blower wheel on a solid shaft with two
concentric type bearings, one on each side of the
blower housing. A fixed−pitch driven pulley is
attached to the fan shaft and an adjustable−pitch
driver pulley is on the motor. The pulleys are
connected using a “V” type belt. (See Fig.5.)
Fig. 5 −Belt Drive Motor Mounting
Belt
Check the belt condition and tension quarterly.
Inspect the belt for signs of cracking, fraying or
glazing along the inside surfaces. Check belt tension
by using a spring-force tool (such as Browning’s Part
Number “Belt Tension Checker” or equivalent tool);
tension should be 6-lbs at a 5/8-in. deflection when
measured at the centerline of the belt span. This point
is at the center of the belt when measuring the
distance between the motor shaft and the blower
shaft.
NOTE: Without the spring−tension tool, place a
straight edge across the belt surface at the pulleys,
then deflect the belt at mid−span using one finger to a
1/2-in. deflection.
Adjust belt tension by loosening the motor mounting
plate front bolts and rear bolt and sliding the plate
toward the fan (to reduce tension) or away from fan
(to increase tension). Ensure the blower shaft and the
motor shaft are parallel to each other (pulleys
aligned). Tighten all bolts when finished.
To replace the belt:
1. Use a belt with same section type or similar size.
Do not substitute a “FHP” type belt. When in-
stalling the new belt, do not use a tool (screw-
driver or pry−bar) to force the belt over the pulley
flanges, this will stress the belt and cause a re-
duction in belt life.
2. Loosen the motor mounting plate front bolts and
rear bolts.
3. Push the motor and its mounting plate towards
the blower housing as close as possible to reduce
the center distance between fan shaft and motor
shaft.
4. Remove the belt by gently lifting the old belt over
one of the pulleys.
5. Install the new belt by gently sliding the belt over
both pulleys and then sliding the motor and plate
away from the fan housing until proper tension is
achieved.
6. Check the alignment of the pulleys, adjust if ne-
cessary.
7. Tighten all bolts.
8. Check the tension after a few hours of runtime
and re−adjust as required.
Adjustable−Pitch Pulley on Motor
The motor pulley is an adjustable−pitch type that
allows a servicer to implement changes in the fan
wheel speed to match as−installed ductwork systems.
The pulley consists of a fixed flange side that faces
the motor (secured to the motor shaft) and a movable
flange side that can be rotated around the fixed
flange side that increases or reduces the pitch
diameter of this driver pulley. (See Fig.6.)
As the pitch diameter is changed by adjusting the
position of the movable flange, the centerline on this
pulley shifts laterally (along the motor shaft). This
creates a requirement for a realignment of the pulleys
after any adjustment of the movable flange. Also
reset the belt tension after each realignment.
Check the condition of the motor pulley for signs of
wear. Glazing of the belt contact surfaces and erosion
on these surfaces are signs of improper belt tension
and/or belt slippage. Pulley replacement may be
necessary.
To change fan speed:
1. Shut off unit power supply.
2. Loosen belt by loosening fan motor mounting
nuts. (See Fig.5.)
3. Loosen movable pulley flange setscrew.
(See Fig.6.)
4. Screw movable flange toward fixed flange to in-
crease speed and away from fixed flange to de-
crease speed. Increasing fan speed increases
load on motor. Do not exceed maximum speed
specified.
5. Set movable flange at nearest keyway of pulley
hub and tighten setscrew to torque specifications.

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509 08 3601 00
To align fan and motor pulleys:
1. Loosen fan pulley setscrews.
2. Slide fan pulley along fan shaft. Make angular
alignment by loosening motor from mounting.
3. Tighten fan pulley setscrews and motor mounting
bolts to torque specifications.
4. Recheck belt tension.
Fig. 6 −Supply−Fan Pulley Adjustment
Bearings
This fan system uses bearings featuring concentric
split locking collars. The collars are tightened through
a cap screw bridging the split portion of the collar.
The cap screw has a Torx T25 socket head. To
tighten the locking collar: Hold the locking collar
tightly against the inner race of the bearing and
torque the cap screw to 65−70 in-lb (7.4−7.9 Nm).
(See Fig.7.)
Fig. 7 −Tightening Locking Collar
Motor
When replacing the motor, also replace the
external−tooth lock washer (star washer) under the
motor mounting base; this is part of the motor
grounding system. Ensure the teeth on the lock
washer are in contact with the motor’s painted base.
Tighten motor mounting bolts to 120 +/−12 in−lbs.
Changing fan wheel speed by changing pulleys: The
horsepower rating of the belt is primarily dictated by
the pitch diameter of the smaller pulley in the drive
system (typically the motor pulley in these units). Do
not install a replacement motor pulley with a smaller
pitch diameter than provided on the original factory
pulley. Change fan wheel speed by changing the fan
pulley (larger pitch diameter to reduce wheel speed,
smaller pitch diameter to increase wheel speed) or
select a new system (both pulleys and matching
belt(s)).
Before changing pulleys to increase fan wheel speed,
check the fan performance at the target speed and
airflow rate to determine new motor loading (bhp).
Using the fan performance tables, confirm that the
motor in this unit is capable of operating at the new
operating condition. Fan shaft loading increases
dramatically as wheel speed is increased.
To reduce vibration, replace the motor’s adjustable
pitch pulley with a fixed pitch pulley (after the final
airflow balance adjustment). This will reduce the
amount of vibration generated by the motor/belt−drive
system.
COOLING
UNIT OPERATION AND SAFETY HAZARD
Failure to follow this warning could cause
personal injury, death and/or equipment damage.
This system uses refrigerant which has higher
pressures than R−410A and other refrigerants. No
other refrigerant may be used in this system.
Gauge set, hoses, and recovery system must be
designed to handle refrigerant. If unsure about
equipment, consult the equipment manufacturer.
!WARNING
Condenser Coil
The condenser coil is new Micro−channel Heat
Exchanger Technology. This is an all−aluminum
construction with louvered fins over single−depth
crosstubes. The crosstubes have multiple small
passages through which the refrigerant passes from
header to header on each end. Tubes and fins are
both aluminum construction. Connection tube joints
are copper. The coil may be one−row or two−row.
Two−row coils are spaced apart to assist in cleaning.

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509 08 3601 00
TUBES
FINS
MANIFOLD
MICROCHANNELS
Fig. 8 −Micro−channel Coils
Evaporator Coil
The evaporator coil is traditional round−tube, plate−fin
technology. Tube and fin construction is of various
optional materials and coatings (see Model Number
Format). Coils are multiple−row.
Coil Maintenance and Cleaning Recommendation
Routine cleaning of coil surfaces is essential to
maintain proper operation of the unit. Elimination of
contamination and removal of harmful residues will
greatly increase the life of the coil and extend the life
of the unit. The following maintenance and cleaning
procedures are recommended as part of the routine
maintenance activities to extend the life of the coil.
Remove Surface Loaded Fibers
Surface loaded fibers or dirt should be removed with
a vacuum cleaner. If a vacuum cleaner is not
available, a soft non−metallic bristle brush may be
used. In either case, the tool should be applied in the
direction of the fins. Coil surfaces can be easily
damaged (fin edges can be easily bent over and
damage to the coating of a protected coil) if the tool is
applied across the fins.
NOTE: Use of a water stream, such as a garden
hose, against a surface loaded coil will drive the fibers
and dirt into the coil. This will make cleaning efforts
more difficult. Surface loaded fibers must be
completely removed prior to using low velocity clean
water rinse.
Periodic Clean Water Rinse
A periodic clean water rinse is very beneficial for coils
that are applied in coastal or industrial environments.
However, it is very important that the water rinse is
made with very low velocity water stream to avoid
damaging the fin edges. Monthly cleaning as
described below is recommended.
Routine Cleaning of Micro−channel Condenser
Coil Surfaces
To clean the Micro−channel condenser coil, chemicals
are NOT to be used; only water is approved as the
cleaning solution. Only clean potable water is
authorized for cleaning Micro−channel condensers.
Carefully remove any foreign objects or debris
attached to the coil face or trapped within the
mounting frame and brackets. Using a high pressure
water sprayer, purge any soap or industial cleaners
from hose and/or dilution tank prior to wetting the coil.
Clean condenser face by spraying the coil core
steadily and uniformly from top to bottom, directing
the spray straight into or toward the coil face. Do not
exceed 900 psig or a 45 degree angle; nozzle must
be at least 12 in. (30 cm) from the coil face. Reduce
pressure and use caution to prevent damage to air
centers (fins). Do not fracture the braze between air
centers and refrigerant tubes. Allow water to drain
from the coil core and check for refrigerant leaks prior
to start−up.
NOTE: Please see the Micro−channel Condenser
Service section for specific information on the coil.
PERSONAL INJURY HAZARD
Failure to follow this caution may result in
personal injury or equipment damage.
Chemical cleaning should NOT be used on the
aluminum Micro−channel condenser. Damage to
the coil may occur. Only approved cleaning is
recommended.
CAUTION
!
Routine Cleaning of Evaporator Coil Sufaces
Monthly cleaning with environmentally sound coil
cleaner is essential to extend the life of coils. This
cleaner is available from FAST Replacement parts
division as part number 1178704 for one gallon
container, and part number 1178705 for a 5 gallon
container. It is recommended that all round tube coil
cleaner as described below. Coil cleaning should be
part of the unit’s regularly scheduled maintenance
procedures to ensure long life of the coil. Failure to
clean the coils may result in reduced durability in the
environment.
Avoid the use of
coil brighteners
acid cleaning prior to painting
high pressure washers
poor quality water for cleaning
Environmentaiiy sound coil cleaner is non−flammable,
hypoallergenic, non−bacterial, and a USDA accepted
biodegradable agent that will not harm coil or
surrounding components such as electrical wiring,
painted metal surfaces, or insulation. Use of
non−recommended coil cleaners is strongly
discouraged since coil and unit durability could be
affected.
Environmentally Sound Coil Cleaner Application
Equipment
2-1/2 gallon garden sprayer

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509 08 3601 00
water rinse with low velocity spray nozzle
PERSONAL INJURY HAZARD
Failure to follow this caution may result in
corrosion and damage to the unit.
Harsh chemicals, household bleach or acid or
basic cleaners should not be used to clean
outdoor or indoor coils of any kind. These
cleaners can be very difficult to rinse out of the
coil and can accelerate corrosion at the fin/tube
interface where dissimilar materials are in contact.
If there is dirt below the surface of the coil, use
the environmentally sound coil cleaner as
described above.
CAUTION
!
PERSONAL INJURY HAZARD
Failure to follow this caution may result in reduced
unit performance.
High velocity water from a pressure washer,
garden hose, or compressed air should never be
used to clean a coil. The force of the wter or air jet
will bend the fin edges and icrease airside
pressure drop.
CAUTION
!
1. Proper eye protection such as safety glasses is
recommended during mixing and application.
2. Remove all surface loaded fibers and dirt with a
vacuum cleaner as described above.
3. Thoroughly wet finned surfaces with clean water
and a low velocity garden hose, being carefull not
to bend fins.
4. Mix environmentally sound coil cleaner in a 2 1/2
gallon garden spryer according to the instructions
included with the cleaner. The optimum solution
temperature is 100°F (38°C).
NOTE: Do NOT USE water in excess of 130°F
(54°C), as the enzymatic activity will be destroyed.
1. Thoroughly apply environmentally sound coil
cleaner solution to all coil surfaces including
finned area, tube sheets and coil headers.
2. Hold garden sprayer nozzle close to finned areas
and apply cleaner with a vertical, up−and−down
motion. Avoid spraying in horizontal pattern to
minimize potential for fin damage.
3. Ensure cleaner thoroughly penetrates deep into
finned areas.
4. Interior and exterior finned areas must be thor-
oughly cleaned.
5. Finned surfaces should remain wet with cleaning
solution for 10 minutes.
6. Ensure surfaces are not allowed to dry before
rinsing. Reapply cleaner as needed to ensure
10−minute saturation is achieved.
7. Thoroghly rinse all surfaces with low velocity
clean water using downward rinsing motion of wa-
ter spray nozzle. Protect fins from damage from
the spray nozzle.
Evaporator Coil Metering Devices
The metering devices are multiple fixed−bore devices
fixed metering device swaged into the horizontal
outlet tubes from the liquid header, located at the
entrance to each evaporator coil circuit path. These
are non−adjustable. Service requires replacing the
entire liquid header assembly.
To check for possible blockage of one or more of
these metering devices, disconnect the supply fan
contactor (IFC) coil, then start the compressor and
observe the frosting pattern on the face of the
evaporator coil. A frost pattern should develop
uniformly across the face of the coil starting at each
horizontal header tube. Failure to develop frost at an
outlet tube can indicate a plugged or a missing orifice.
Refrigerant System Pressure Access Ports
There are two access ports in the system −on the
suction tube near the compressor and on the
discharge tube near the compressor. These are brass
fittings with black plastic caps. The hose connection
fittings are standard 1/4 SAE male flare couplings.
The brass fittings are two−piece High Flow valves,
with a receptacle base brazed to the tubing and an
integral spring-closed check valve core screwed into
the base. (See Fig.9.) This check valve is
permanently assembled into this core body and
cannot be serviced separately; replace the entire core
body if necessary. Service tools are available from
RCD that allow the replacement of the check valve
core without having to recover the entire system
refrigerant charge. Apply compressor refrigerant oil to
the check valve core’s bottom O-ring. Install the fitting
body with 96 +/−10 in-lbs of torque; do not
overtighten.
R−410A REFRIGERANT
This unit is designed for use with R−410A refrigerant.
Do not use any other refrigerant in this system.
R−410A refrigerant is provided in pink (rose) colored
cylinders. These cylinders are available with and
without dip tubes; cylinders with dip tubes will have a
label indicating this feature. For a cylinder with a dip
tube, place the cylinder in the upright position (access
valve at the top) when removing liquid refrigerant for
charging. For a cylinder without a dip tube, invert the
cylinder (access valve on the bottom) when removing
liquid refrigerant.

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509 08 3601 00
Because R−410A refrigerant is a blend, it is strongly
recommended that refrigerant always be removed
from the cylinder as a liquid. Admit liquid refrigerant
into the system in the discharge line. If adding
refrigerant into the suction line, use a commercial
metering/expansion device at the gauge manifold;
remove liquid from the cylinder, pass it through the
metering device at the gauge set and then pass it into
the suction line as a vapor. Do not remove R−410A
refrigerant from the cylinder as a vapor.
Refrigerant Charge
Amount of refrigerant charge is listed on the unit’s
nameplate. Refer to FAST Charging, Recovery,
Recycling and Reclamation training manual and the
following procedures.
Unit panels must be in place when unit is operating
during the charging procedure. To prepare the unit for
charge adjustment.
No Charge
Use standard evacuating techniques. After
evacuating system, weigh in the specified amount of
refrigerant.
Low−Charge Cooling
Using Cooling Charging Charts (Figs.10, 11, 12, and
13), vary refrigerant until the conditions of the
appropriate chart are met. Note the charging charts
are different from the type normally used. Charts are
based on charging the units to the correct superheat
for the various operating conditions. Accurate
pressure gauge and temperature sensing device are
required. Connect the pressure gauge to the service
port on the suction line. Mount the temperature
sensing device on the suction line and insulate it so
that outdoor ambient temperature does not affect the
reading. Indoor−air cfm must be within the normal
operating range of the unit.
To Use Cooling Charging Charts
Select the appropriate unit charging chart from
Figs.10, 11, 12, and 13.
Sizes RGS090 and RGS120 each have one cooling
charging chart
Size RGS150 has two cooling charging charts:
Circuit A and Circuit B
Take the outdoor ambient temperature and read the
suction pressure gauge. Refer to chart to determine
what suction temperature should be. If suction
temperature is high, add refrigerant. If suction
temperature is low, carefully recover some of the
charge. Recheck the suction pressure as charge is
adjusted.
For RGS150 size, perform this procedure once for
Circuit A (using the Circuit A chart) and once for
Circuit B (using the Circuit B chart).
Fig. 9 −CoreMax Access Port Assembly
1/2-20 UNF RH
30
0.596
SEAT CORE
WASHER DEPRESSOR PER ARI 720
+.01/-.035
FROM FACE OF BODY
7/16-20 UNF RH
O-RING
45
torqued into the seat. Appropriate handling is
required to not scratch or dent the surface.
1/2” HEX
This surface provides a metal to metal seal when
o
o
(Part No. 1173177)
⅝” HEX .47
EXAMPLE:
Model RGS120
Circuit A:
Outdoor Temperature 85F (29C)................
Suction Pressure 125 psig (860 kPa)..............
Suction Temperature should be 58F (14C).......
Circuit B:
Outdoor Temperature 85F (29C)................
Suction Pressure 120 psig (830 kPa)..............
Suction Temperature should be 60F (16C).......

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COOLING CHARGING CHARTS
Fig. 10 −Cooling Charging Charts

11
509 08 3601 00
COOLING CHARGING CHARTS
Fig. 11 −Cooling Charging Chart

12
509 08 3601 00
COOLING CHARGING CHARTS
Fig. 12 −Cooling Charging Chart (Circuit A)
12.5 Ton

13
509 08 3601 00
COOLING CHARGING CHARTS
Fig. 13 −Cooling Charging Chart (Circuit B)
12.5 Ton

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509 08 3601 00
Table 1 – Cooling Service Analysis
PROBLEM CAUSE REMEDY
Compressor and Condenser
Fan Will Not Start.
Power failure. Call power company.
Fuse blown or circuit breaker tripped. Replace fuse or reset circuit breaker.
Defective thermostat, contactor,
transformer, or control relay. Replace component.
Insufficient line voltage. Determine cause and correct.
Incorrect or faulty wiring. Check wiring diagram and rewire correctly.
Thermostat setting too high. Lower thermostat setting below room
temperature.
Compressor Will Not Start
But Condenser Fan Runs.
Faulty wiring or loose connections in
compressor circuit. Check wiring and repair or replace.
Compressor motor burned out, seized, or
internal overload open. Determine cause. Replace compressor.
Defective run/start capacitor, overload,
start relay. Determine cause and replace.
One leg of three−phase power dead. Replace fuse or reset circuit breaker.
Determine cause.
Compressor Cycles (other
than normally satisfying
thermostat).
Refrigerant overcharge or undercharge. Recover refrigerant, evacuate system, and
recharge to nameplate.
Defective compressor. Replace and determine cause.
Insufficient line voltage. Determine cause and correct.
Blocked condenser. Determine cause and correct.
Defective run/start capacitor, overload, or
start relay. Determine cause and replace.
Defective thermostat. Replace thermostat.
Faulty condenser−fan motor or capacitor. Replace.
Restriction in refrigerant system. Locate restriction and remove.
Compressor Operates
Continuously.
Dirty air filter. Replace filter.
Unit undersized for load. Decrease load or increase unit size.
Thermostat set too low. Reset thermostat.
Low refrigerant charge. Locate leak; repair and recharge.
Leaking valves in compressor. Replace compressor.
Air in system. Recover refrigerant, evacuate system, and
recharge.
Condenser coil dirty or restricted. Clean coil or remove restriction.
Excessive Head Pressure.
Dirty air filter. Replace filter.
Dirty condenser coil. Clean coil.
Refrigerant overcharged. Recover excess refrigerant.
Air in system. Recover refrigerant, evacuate system, and
recharge.
Condenser air restricted or air
short−cycling. Determine cause and correct.
Head Pressure Too Low.
Low refrigerant charge. Check for leaks; repair and recharge.
Compressor valves leaking. Replace compressor.
Restriction in liquid tube. Remove restriction.
Excessive Suction Pressure.
High head load. Check for source and eliminate.
Compressor valves leaking. Replace compressor.
Refrigerant overcharged. Recover excess refrigerant.
Suction Pressure Too Low.
Dirty air filter. Replace filter.
Low refrigerant charge. Check for leaks; repair and recharge.
Metering device or low side restricted. Remove source of restriction.
Insufficient evaporator airflow. Increase air quantity. Check filter and replace if
necessary.
Temperature too low in conditioned area. Reset thermostat.
Outdoor ambient below 25 F. Install low−ambient kit.
Evaporator Fan Will Not Shut
Off. Time off delay not finished. Wait for 30−second off delay.
Compressor Makes
Excessive Noise. Compressor rotating in wrong direction. Reverse the 3−phase power leads.

15
509 08 3601 00
Compressors
Lubrication
Compressors are charged with the correct amount of
oil at the factory.
UNIT DAMAGE HAZARD
Failure to follow this caution may result in damage
to components.
The compressor is in a refrigerant system and
uses a polyolester (POE) oil. This oil is extremely
hygroscopic, meaning it absorbs water readily.
POE oils can absorb 15 times as much water as
other oils designed for HCFC and CFC
refrigerants. Avoid exposure of the oil to the
atmosphere.
CAUTION
!
PERSONAL INJURY AND ENVIRONMENTAL
HAZARD
Failure to follow this warning could result in
personal injury or death.
Relieve pressure and recover all refrigerant before
system repair or final unit disposal.
Wear safety glasses and gloves when handling
refrigerants.
Keep torches and other ignition sources away
from refrigerants and oils.
!WARNING
Replacing Compressor
The compressor used with refrigerant contains a POE
oil. This oil has a high affinity for moisture. Do not
remove the compressor’s tube plugs until ready to
insert the unit suction and discharge tube ends.
Compressor mounting bolt torque is 65−75 in-lbs
(7.3−8.5 N-m).
Compressor Rotation
On 3-phase units with scroll compressors, it is
important to be certain compressor is rotating in the
proper direction. To determine whether or not
compressor is rotating in the proper direction:
1. Connect service gauges to suction and discharge
pressure fittings.
2. Energize the compressor.
3. The suction pressure should drop and the dis-
charge pressure should rise, as is normal on any
start−up.
NOTE: If the suction pressure does not drop and the
discharge pressure does not rise to normal levels:
4. Note that the evaporator fan is probably also ro-
tating in the wrong direction.
5. Turn off power to the unit.
6. Reverse any two of the unit power leads.
7. Reapply power to the compressor.
The suction and discharge pressure levels should
now move to their normal start−up levels.
NOTE: When the compressor is rotating in the wrong
direction, the unit makes an elevated level of noise
and does not provide cooling.
Filter Drier
Replace whenever refrigerant system is exposed to
atmosphere. Only use factory specified liquid−line
filter driers with working pressures no less than 650
psig. Do not install a suction−line filter drier in liquid
line. A liquid−line filter drier designed for use with
refrigerant is required on every unit.
Condenser−Fan Adjustment (RGS090−120)
1. Shut off unit power supply. Install lockout tag.
2. Remove condenser-fan assembly (grille, motor,
and fan).
3. Loosen fan hub setscrews.
4. Adjust fan height as shown in Fig.14.
5. Tighten setscrews to 84 in-lbs (9.5 N-m).
6. Replace condenser-fan assembly.
CONDUI
T
0.14 in +0.0/−0.03
Fig. 14 −Condenser Fan Adjustment (090−120)
Condenser−Fan Adjustment (RGS150)
1. Shut off unit power supply. Install lockout tag.
2. Remove condenser fan grille.
3. Loosen fan hub setscrews.
4. Adjust fan height as shown in Fig.15.
5. Tighten set screws to 84 in-lbs (9.5 N-m).
6. Replace fan grille.
Fig. 15 −Condenser Fan Adjustment (150)
Troubleshooting Cooling System
Refer to Table 1 for additional troubleshooting topics.

16
509 08 3601 00
CONVENIENCE OUTLET
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in
personal injury or death.
Units with convenience outlet circuits may use
multiple disconnects. Check convenience outlet
for power status before opening unit for service.
Locate its disconnect switch, if appropriate, and
open it. Tag−out this switch, if necessary.
!WARNING
A Non−powered convenience outlets is offered and
provides a 125-volt GFCI (ground−fault
circuit−interrupter) duplex receptacle rated at 15-A
behind a hinged waterproof access cover, located on
the end panel of the unit. (See Fig.16.)
Conv Outlet
GFCI
Fig. 16 −Convenience Outlet Location
Non−Powered Type
This type requires the field installation of a
general−purpose 125−volt 15−A circuit powered from
a source elsewhere in the building. Observe national
and local codes when selecting wire size, fuse or
breaker requirements and disconnect switch size and
location. Route 125−v power supply conductors into
the bottom of the utility box containing the duplex
receptacle.
Duty Cycle
The unit−powered convenience outlet has a duty
cycle limitation. The transformer is intended to
provide power on an intermittent basis for service
tools, lamps, etc; it is not intended to provide
15−amps loading for continuous duty loads (such as
electric heaters for overnight use). Observe a 50%
limit on circuit loading above 8−amps (i.e., limit loads
exceeding 8−amps to 30 minutes of operation every
hour).
Maintenance
Periodically test the GFCI receptacle by pressing the
TEST button on the face of the receptacle. This
should cause the internal circuit of the receptacle to
trip and open the receptacle. Check for proper
grounding wires and power line phasing if the GFCI
receptacle does not trip as required. Press the
RESET button to clear the tripped condition.
Using Unit−Mounted Convenience Outlets
Units with unit−mounted convenience outlet circuits
will often require that two disconnects be opened to
de−energize all power to the unit. Treat all units as
electrically energized until the convenience outlet
power is also checked and de−energization is
confirmed. Observe National Electrical Code Article
210, Branch Circuits, for use of convenience outlets.
SMOKE DETECTORS
Supply Air Smoke detectors are available as
factory−installed options without or with economizer .
All components necessary for operation are
factory−provided and mounted. The unit is
factory−configured for immediate smoke detector
shutdown operation; additional wiring or modifications
to unit terminal board may be necessary to complete
the unit and smoke detector configuration to meet
project requirements.
System
The smoke detector system consists of a four−wire
controller and one or two sensors. Its primary function
is to shut down the rooftop unit in order to prevent
smoke from circulating throughout the building. It is
not to be used as a life saving device.
Controller
The controller (see Fig.17) includes a controller
housing, a printed circuit board, and a clear plastic
cover. The controller can be connected to one or two
compatible duct smoke sensors. The clear plastic
cover is secured to the housing with a single captive
screw for easy access to the wiring terminals. The
controller has three LEDs (for Power, Trouble and
Alarm) and a manual test/reset button (on the cover
face).

17
509 08 3601 00
Duct smoke sensor
controller
Fastener
(2X)
Contr oll er cover
Condui t support pl ate
Terminal block cover
Contr oll er housi ng
and electronics
Al arm Power
Test/reset
switch
Tr o ub l e
Fig. 17 −Controller Assembly
Conduit couplings
(supplied by installer)
Terminal block cover
Conduit nuts
(supplied by installer)
Sensor
The sensor (see Fig.18) includes a plastic housing, a
printed circuit board, a clear plastic cover, a sampling
tube inlet and an exhaust tube. The sampling tube
(when used) and exhaust tube are attached during
installation. The sampling tube varies in length
depending on the size of the rooftop unit. The clear
plastic cover permits visual inspections without having
to disassemble the sensor. The cover attaches to the
sensor housing using four captive screws and forms
an airtight chamber around the sensing electronics.
Each sensor includes a harness with an RJ45
terminal for connecting to the controller. Each sensor
has four LEDs (for Power, Trouble, Alarm and Dirty)
and a manual test/reset button (on the left−side of the
housing).
Air is introduced to the duct smoke detector sensor’s
sensing chamber through a sampling tube that
extends into the HVAC duct and is directed back into
the ventilation system through a (shorter) exhaust
tube. The difference in air pressure between the two
tubes pulls the sampled air through the sensing
chamber. When a sufficient amount of smoke is
detected in the sensing chamber, the sensor signals
an alarm state and the controller automatically takes
the appropriate action to shut down fans and blowers,
change over air handling systems, notify the fire
alarm control panel, etc.
The sensor uses a process called differential sensing
to prevent gradual environmental changes from
triggering false alarms. A rapid change in
environmental conditions, such as smoke from a fire,
causes the sensor to signal an alarm state but dust
and debris accumulated over time does not.
Duct smoke sensor
Exhaust tube
Pl ug
Sensor housing
and electronics
Exhaust gasket
Coupli ng
Sensor cover
Detail A
Magnetic
test/reset
switch
Al arm
Tr o ub l e
Power
Dirty
Fig. 18 −Smoke Detector Sensor
Sampling tube
(ordered separately)
TSD-CO2
(ordering option)
Intake
gasket
See
Detail A
Cover gasket
(ordering option)
For installations using two sensors, the duct smoke
detector does not differentiate which sensor signals
an alarm or trouble condition.
Smoke Detector Locations
Supply Air — The Supply Air smoke detector sensor
is located to the left of the unit’s indoor (supply) fan.
(See Fig.19.) Access is through the fan access panel.
There is no sampling tube used at this location. The
sampling tube inlet extends through the side plate of
the fan housing (into a high pressure area). The
controller is located on a bracket to the right of the
return filter, accessed through the lift−off filter panel.

18
509 08 3601 00
Smoke Detector Sensor
Fig. 19 −Typical Supply Air Smoke Detector
Sensor Location
FIOP Smoke Detector Wiring and Response
All units: FIOP smoke detector is configured to
automatically shut down all unit operations when
smoke condition is detected. See Fig.20, Smoke
Detector Wiring.
Highlight A: JMP 3 is factory−cut, transferring unit
control to smoke detector.
Highlight B: Smoke detector NC contact set will open
on smoke alarm condition, de−energizing the ORN
conductor.
A
E
F
C
D
B
Fig. 20 −Typical Smoke Detector System Wiring
Highlight C: 24−v power signal via ORN lead is
removed at Smoke Detector input on LCTB; all unit
operations cease immediately.
Highlight D: On smoke alarm condition, the smoke
detector NO Alarm contact will close, supplying 24−v
power to GRA conductor.
Highlight E: GRA lead at Smoke Alarm input on LCTB
provides 24−v signal to FIOP DDC control.
Using Remote Logic: Five conductors are provided
for field use (see Highlight F) for additional
annunciation functions.
Additional Application Data — Refer to Catalog No.
HKRNKA−1XA for discussions on additional control
features of these smoke detectors including multiple
unit coordination. (See Fig.20.)
Sensor and Controller Tests
Sensor Alarm Test
The sensor alarm test checks a sensor’s ability to
signal an alarm state. This test requires that you use
a field provided SD−MAG test magnet.
OPERATIONAL TEST HAZARD
Failure to follow this caution may result in
personnel and authority concern.
This test places the duct detector into the alarm
state. Unless part of the test, disconnect all
auxiliary equipment from the controller before
performing the test. If the duct detector is
connected to a fire alarm system, notify the
proper authorities before performing the test.
CAUTION
!

19
509 08 3601 00
Sensor Alarm Test Procedure
1. Hold the test magnet where indicated on the side
of the sensor housing for seven seconds.
2. Verify that the sensor’s Alarm LED turns on.
3. Reset the sensor by holding the test magnet
against the sensor housing for two seconds.
4. Verify that the sensor’s Alarm LED turns off.
Controller Alarm Test
The controller alarm test checks the controller’s ability
to initiate and indicate an alarm state.
OPERATIONAL TEST HAZARD
Failure to follow this caution may result in
personnel and authority concern.
This test places the duct detector into the alarm
state. Disconnect all auxiliary equipment from the
controller before performing the test. If the duct
detector is connected to a fire alarm system,
notify the proper authorities before performing the
test.
CAUTION
!
Controller Alarm Test Procedure
1. Press the controller’s test/reset switch for seven
seconds.
2. Verify that the controller’s Alarm LED turns on.
3. Reset the sensor by pressing the test/reset
switch for two seconds.
4. Verify that the controller’s Alarm LED turns off.
Dirty Controller Test
The dirty controller test checks the controller’s ability
to initiate a dirty sensor test and indicate its results.
OPERATIONAL TEST HAZARD
Failure to follow this caution may result in
personnel and authority concern.
Pressing the controller’s test/reset switch for
longer than seven seconds will put the duct
detector into the alarm state and activate all
automatic alarm responses.
CAUTION
!
Dirty Controller Test Procedure
Press the controller’s test/reset switch for two
seconds.
Verify that the controller’s Trouble LED flashes.
Dirty Sensor Test
The dirty sensor test provides an indication of the
sensor’s ability to compensate for gradual
environmental changes. A sensor that can no longer
compensate for environmental changes is considered
100% dirty and requires cleaning or replacing. You
must use a field provided SD−MAG test magnet to
initiate a sensor dirty test. The sensor’s Dirty LED
indicates the results of the dirty test as shown in
Table 2.
OPERATIONAL TEST HAZARD
Failure to follow this caution may result in
personnel and authority concern.
Holding the test magnet against the sensor
housing for more than seven seconds will put the
duct detector into the alarm state and activate all
automatic alarm responses.
CAUTION
!
Table 2 – Dirty LED Test
FLASHES DESCRIPTION
10-25% dirty. (Typical of a newly installed detector)
225-50% dirty
351-75% dirty
476-99% dirty
Dirty Sensor Test Procedure
1. Hold the test magnet where indicated on the side
of the sensor housing for two seconds.
2. Verify that the sensor’s Dirty LED flashes.
OPERATIONAL TEST HAZARD
Failure to follow this caution may result in
personnel and authority concern.
Changing the dirty sensor test operation will put
the detector into the alarm state and activate all
automatic alarm responses. Before changing dirty
sensor test operation, disconnect all auxiliary
equipment from the controller and notify the
proper authorities if connected to a fire alarm
system.
CAUTION
!
Changing the Dirty Sensor Test
By default, sensor dirty test results are indicated by:
The sensor’s Dirty LED flashing.
The controller’s Trouble LED flashing.
The controller’s supervision relay contacts toggle.
The operation of a sensor’s dirty test can be changed
so that the controller’s supervision relay is not used to
indicate test results. When two detectors are
connected to a controller, sensor dirty test operation
on both sensors must be configured to operate in the
same manner.
To Configure the Dirty Sensor Test Operation
1. Hold the test magnet where indicated on the side
of the sensor housing until the sensor’s Alarm
LED turns on and its Dirty LED flashes twice (ap-
proximately 60 seconds).
2. Reset the sensor by removing the test magnet
then holding it against the sensor housing again
until the sensor’s Alarm LED turns off (approxim-
ately 2 seconds).
Remote Station Test
The remote station alarm test checks a test/reset
station’s ability to initiate and indicate an alarm state.

20
509 08 3601 00
OPERATIONAL TEST HAZARD
Failure to follow this caution may result in
personnel and authority concern.
This test places the duct detector into the alarm
state. Unless part of the test, disconnect all
auxiliary equipment from the controller before
performing the test. If the duct detector is
connected to a fire alarm system, notify the
proper authorities before performing the test.
CAUTION
!
SD−TRK4 Remote Alarm Test Procedure
1. Turn the key switch to the RESET/TEST position
for seven seconds.
2. Verify that the test/reset station’s Alarm LED
turns on.
3. Reset the sensor by turning the key switch to the
RESET/TEST position for two seconds.
4. Verify that the test/reset station’s Alarm LED
turns off.
Remote Test/Reset Station Dirty Sensor Test
The test/reset station dirty sensor test checks the
test/reset station’s ability to initiate a sensor dirty test
and indicate the results. It must be wired to the
controller as shown in Fig. 21 and configured to
operate the controller’s supervision relay. For more
information, see “Changing the Dirty Sensor Test.”
1
12
14
13
19
15
2
20
3
Reset/Test
Trouble
Power
Alarm
Supervision relay
contacts [3]
5
4
1
3
2
SD-TRK4
2
1
TB3
18 Vdc ( )
+
18 Vdc ( )
−
Auxiliary
equipment
+
−
Wire must be
added by installer
Smoke Detector Controller
Fig. 21 −Remote Test/Reset Station Connections
OPERATIONAL TEST HAZARD
Failure to follow this caution may result in
personnel and authority concern.
If the test/reset station’s key switch is left in the
RESET/TEST position for longer than seven
seconds, the detector will automatically go into
the alarm state and activate all automatic alarm
responses.
CAUTION
!
OPERATIONAL TEST HAZARD
Failure to follow this caution may result in
personnel and authority concern.
Holding the test magnet to the target area for
longer than seven seconds will put the detector
into the alarm state and activate all automatic
alarm responses.
CAUTION
!
Dirty Sensor Test Using an SD−TRK4
1. Turn the key switch to the RESET/TEST position
for two seconds.
2. Verify that the test/reset station’s Trouble LED
flashes.
Detector Cleaning
Cleaning the Smoke Detector
Clean the duct smoke sensor when the Dirty LED is
flashing continuously or sooner if conditions warrant.
OPERATIONAL TEST HAZARD
Failure to follow this caution may result in
personnel and authority concern.
If the smoke detector is connected to a fire alarm
system, first notify the proper authorities that the
detector is undergoing maintenance then disable
the relevant circuit to avoid generating a false
alarm.
CAUTION
!
1. Disconnect power from the duct detector then re-
move the sensor’s cover. (See Fig.22.)
Airow
HVAC duct
Sampling
tube
Retainer
clip
Optic
plate
Optic
housing
Sensor
housing
Fig. 22 −Sensor Cleaning Diagram