American Standard YCY024G1L Owner's manual

All phases of this installation must comply with the NATIONAL, STATE & LOCAL CODES. In the absence of local codes, the
installation must conform with National Electric Code -- ANSI/NFPA 70 or "LATEST REVISION."
© 2003 American Standard Inc. All rights reserved
YCY-IOM-1E
18-EB21D7-6
INSTALLATION
OPERATION
MAINTENANCE
ALL phases of this installation must comply with
NATIONAL, STATE AND LOCAL CODES
IMPORTANT — This Document is customer property and is to remain with this unit. Please return to service information pack upon completion of work.
Single Package Gas/Electric
14 SEER Convertible
2 - 5Ton
Model: YCY024G1L
YCY024G1M
YCY030G1L
YCY030G1M
YCY036G1M
YCY036G1H
YCY042G1M
YCY048G1H
YCY060G1M
BAYLIFT002A
LIFTING LUG KIT
HAZARDOUS VOLTAGE - DISCONNECT POWER BEFORE SERVICING
WARNING:
Since The Trane Companyhas a policy of continuous product and product data improvement,
it reserves the right to change design and specification without notice. 11/12

Page 2
GENERAL INFORMATION
IMPORTANT: Read this entire manual before
beginning installation procedures.
▲WARNING:BODILY INJURY CAN RESULT FROM
HIGH VOLTAGE ELECTRICAL COMPONENTS, FAST MOVING FANS,
AND COMBUSTIBLE GAS. FOR PROTECTION FROM THESE
INHERENT HAZARDS DURING INSTALLATION AND SERVICING,
THE ELECTRICAL SUPPLY MUST BE DISCONNECTED AND THE
MAIN GAS VALVE MUST BE TURNED OFF. IF OPERATING CHECKS
MUST BE PERFORMED WITH THE UNIT OPERATING, IT IS THE
TECHNICIANS RESPONSIBILTY TO RECOGNIZE THESE HAZARDS
AND PROCEED SAFELY.
Readthismanualcarefullybeforeattemptingtoinstall,operate,
or perform maintenance on this unit. Installation and mainte-
nance should be performed by qualified service technicians
only.
As shipped from the factory, this unit is for use with natural gas
only, and is listed by Underwriters Laboratory.
Model YCY-G heating/cooling units are designed for outdoor
mounting with a vertical condenser discharge. They can be
located either at ground level or on a roof, in accordance with
local codes or National Fuel Gas Code (ANSI-Z223.1A) Latest
Revision.Sincetheseunitsaredesignedexclusivelyforoutdoor
operation, additional flue venting systems are not required.
Each unit contains an operating charge of Refrigerant-22 as
shipped.
INSPECTION
1. Checkfordamageaftertheunitisunloaded.Reportpromptly,
to the carrier, any damage found to the unit. Do not drop the
unit.
IMPORTANT: The use of “spreader bars” is required
whenhoistingtheunit(topreventdamageto sides and
top).
2. Check the unit’s nameplate to determine if the unit is correct
for the intended application. The power supply must be
adequate for both the unit and all accessories.
3. Check to be sure the refrigerant charge has been retained
during shipment. Access to 1/4" flare pressure taps may be
gained by removing the furnace compartment access panel.
Indicates a potentially hazardous situation which, if not avoided, could
result in death or serious injury.
WARNING:
CAUTION: Indicates a potentially hazardous situation which, if not avoided, may
result in minor or moderate injury.It may also be used to alert against unsafe practices
and where property-damage-only accidents could occur.
▲
▲
Warnings and Cautions appear at appropriate locations throughout this manual.
Read these carefully.
NOTICE
IMPORTANT: DONOTCONNECTGASPIPINGTOTHEUNIT
UNTIL A LINE PRESSURE TEST HAS BEEN COMPLETED.
DAMAGE TO THE GAS VALVE MAY RESULT IN AN UNSAFE
CONDITION. THIS UNIT SHOULD NEVER BE EXPOSED TO
GAS LINE PRESSURE IN EXCESS OF 14 INCHES WATER
COLUMN. (1/2 PSIG)
IMPORTANT: RECONNECT ALL GROUNDING DEVICES.
ALLPARTSOFTHISPRODUCTCAPABLEOFCONDUCTING
ELECTRICAL CURRENT ARE GROUNDED. IF GROUNDING
WIRES, SCREWS, STRAPS, CLIPS NUTS OR WASHERS
USED TO COMPLETE A PATH TO GROUND ARE REMOVED
FORSERVICE,THEYMUSTBERETURNEDTOTHEIRORIGI-
NAL POSITION AND PROPERLY FASTENED.
IMPORTANT: ALLPOWERLEGSMAYNOTBE BROKENBY
CONTACTORS. SEE WIRING DIAGRAM ON UNIT CONTROL
BOX COVER.
THIS UNIT, AS SHIPPED FROM THE FACTORY, IS DE-
SIGNED FOR NATURAL GAS ONLY.
BEFORESTARTINGTHECOMPRESSOR,THECRANKCASE
HEATER SHOULD BE ENERGIZED FOR EIGHT HOURS
The following warning complies with State of California law, Proposition 65.
▲ WARNING: Hazardous Gasses!
Exposure to fuel substances or by-products of incomplete
fuel combustion is believed by the state of California to
cause cancer, birth defects, or other reproductive harm.

Page 3
ROOF INSULATION
ROOF DECK
FIELD SUPPLIED
RIGID INSULATION
SUPPLY AIR
DUCT RETURN AIR
DUCT
ROOF MOUNTING
CURB
FIELD SUPPLIED
CANT STRIP
FIELD SUPPLIE
D
SUPPORTS
AT EACH END
OF CURB
ROOFING
SEE NOTE 1
SEE NOTE 2
TYPICAL ROOFTOP INSTALLATION WITH BAYCURB030A
(YCY024-060G Models)
TYPICAL ROOFTOP INSTALLATION WITH FULL PERIMETER CURBS
(YCY024-060G Models)
1
2
NOTES:
1. The YCY024,030,036,042G models extend out past
this end of the curb ONLY.
2. Only the YCY048,060G models extend past both the
end and the side of the curb as illustrated.
ROOF INSULATION
ROOF DECK
FIELD SUPPLIED
RIGID INSULATION
SUPPLY AIR
DUCT RETURN AIR
DUCT
ROOF MOUNTING
CURB
FIELD SUPPLIED
CANT STRIP
FIELD SUPPLIE
D
SUPPORTS
AT EACH END
OF CURB
ROOFING

Page 4
DIMENSIONAL DATA
3 YCY024-060G OUTLINE – BACK
MODEL CORNER WEIGHT (LBS) UNIT
WEIGHT ABCDE FGH J KLMNP
W1 W2 W3 W4
YCY024G-L 91 77 99 117 384
64 36 29-3/16 18-9/16 11-1/16 6-9/16 11-1/8 17
20-5/16 29-1/2
17-1/2 10 3 8-3/4
YCY024G-M 86 73 108 128 395 21-1/2 29-1/2
YCY030G-L 115 91 92 116 414 19-5/16 28-1/2
YCY030G-M 110 87 101 127 425 19-5/16 28-1/2
YCY036G-M 115 90 107 136 448 19-1/2 28-7/32
YCY036G-H 114 91 110 138 453 19-13/16 28-1/2
YCY042G-M 114 91 110 138 453 19-13/16 28-1/2
YCY048G-H 140 114 142 176 572 65-1/8 45 33-3/8 21-1/16 15-1/16 4-15/16 9-1/8 21-15/16 25 29-7/32 20 14 3-1/2 8-5/16
YCY060G-M 145 118 147 182 592 25 29-7/32

Page 5
4
DIMENSIONAL DATA
YCY024-060G OUTLINE – FRONT
MODEL A B C D
YCY024G-L,-M
YCY030G-L,-M
YCY036G-M,-H
YCY042G-M
64 36 29-3/16 27-1/2
YCY048G-H
YCY060G-M 65-1/8 45 33-3/8 27-15/1
6
RECOMMENDED SERVICE CLEARANC
E
BACK * 6.0"
LEFT SIDE 30.0"
RIGHT SIDE 24.0"
FRONT SIDE 42.0"
* 18" WITH FRESH AIR ACCESSORY
* 30" WITH ECONOMIZER
CLEARANCE TO
COMBUSTIBLE MATERIAL
BOTTOM 0.0"
BACK 1.0"
LEFT SIDE 6.0"
RIGHT SIDE 6.0"
FRONT SIDE 12.0"
TOP 36.0"

Page 6
5
6
CONVERTING HORIZONTAL TO DOWNFLOW
REQUIRED CLEARANCE FOR UNIT INSTALLATION
AND ROOF PENETRATION HOLE SIZE REQUIRED
HEATER EXCHANGER
TUBES
HORIZONTAL SUPPLY
AIR COVER
HORIZONTAL RETURN
AIR COVER
SHEET METAL
SCREWS
EF
HOLE IN ROOF
WOOD NAILER
SIDE RAIL
SERVICE
CLEARANCE
LINES
SERVICE
CLEARANCE
LINES
A
B
C
D
SUPPLY AIR
RETURN AIR
NOTE
SUPPLY OPENING
1. REMOVE SCREW NEAREST TO THE
OPENINGANDPULLTHEPANELFIRMLY
TOWARDTHEOUTSIDEOFTHEUNITTO
DISENGAGE THE BACK ATTACHMENT.
RETURN OPENING
2. REMOVE RIGHT HAND SCREW AND
MOVE PANEL TO THE RIGHT OR RE-
MOVE BOTH SCREWS.
3.REMOVEEXTERIORGASKETMATERIAL.
SERVICE CLEARANCE & PENETRATION DIMENSIONS
MODEL NO. A B C D E F
YCY024-042G 42" 30" *12" 30" 44" 25
"
YCY048-060G 42" 30" *12" 36" 50" 25
"
* 18" WITH FRESH AIR ACCESSORY
* 30" WITH ECONOMIZER

Page 7
LOCATIONS AND RECOMMENDATIONS
HORIZONTAL AIRFLOW APPLICATION
1. Theseunitsaredesigncertifiedforoutdoorinstallations. These
units may be installed directly on wood flooring or on Class A,
Class B, or Class C roof covering material. The discharge air
from the condenser fans must be unrestricted for a minimum of
3 feet above the unit.
NOTE: The unit is shipped for horizontal installation.
TheAirInlet Hood in the combustionblower access panelmust
have adequate clearance around the air opening into the
combustion area. See Outline Drawing, Figure 3.
Examine all flue product-carrying areas of the furnace, its vent
system, and the main burner for safe operation. A periodic
inspectionof the furnaceshould bemadeby a qualified service
agency at the start of each heating season.
ReplacementpartslistforthisGas/ElectricAirConditioner,maybe
obtained by contacting your local manufacturer representative.
NOTE: If any internal accessories are to be added to the unit,
install them at the shop if at all practical.
2. Location of the unit must allow service clearance around it.
Clearance of the unit must be given careful consideration. See
Figures 2, 3, and 4.
IMPORTANT: Air outlet duct must have 1" clearance to
combustible material downstream from the unit.
3. Check the handling facilities to ensure the safety of personnel
and the unit(s).
4. CAUTION MUST BE TAKEN AT ALL TIMES TO AVOID
PERSONAL INJURIES AND/OR DAMAGE TO EQUIPMENT
5. The unit must be mounted level for proper drainage of water
through the holes in the base pan.
6. The unit must not be exposed to direct roof water runoff.
7. Flexible duct connectors must be of a flame retardant material.
All duct work outside of the structure must be insulated and
weatherproofed in accordance with local codes.
8. Holesthroughexteriorwallsmustbe sealed in accordance with
local codes.
9. All fabricated outdoor ducts should be as short as possible.
CLEARANCES
1. The recommended clearances for single-unit installations are
illustrated in Figure 4. These minimum requirements are not
only an important consideration when determining unit place-
ment, but they are also essential to ensure adequate service-
ability, maximum capacity, and peak operating efficiency.
2. Any reduction of the unit clearances indicated in these illustra-
tionsmayresultin condenser coil starvation or the recirculation
of warm condenser air. Actual clearances which appear to be
inadequate should be reviewed with a local engineer.
3. See the unit’s nameplate for the absolute minimum clearance
between the unit and any combustible surface(s).
IMPORTANT:
1. Removethe FlueandAirInlet Hoodwithgasket fromthereturn
air section of the unit.
Thescrewsthatattachtheflueandairinlethoodwillbeinstalled
in their proper location at the factory. Therefore, they must be
removedand then used toattach theflue andthe airinlet hood.
2. Remove the packaging material from the components and
secure the Flue and Air Inlet Hood with the gasket to the unit
with sheet metal screws as illustrated in Figure 5. See “Firing
Rate Selection” section for additional information.
NOTE: Outdoor air or other requirements during heating
operation that result in supply air temperatures below 80
degrees F or return air temperatures below 50 degrees F may
cause flue gas condensate to form and is to be avoided.
DOWNFLOW APPLICATION -- CURB MOUNTING
1. The Roof Mounting Curb, (field assembled
BAYCURB030,038,033,034A), or a field fabricated curb must
be in place before the unit is hoisted to the roof top.
2. TheRoofMounting Curb(frame)mustbeinstalled onaflat,
level section of the roof (maximum of 1/4" per foot pitch)
and provide a level mounting surface for the unit. In
addition,besuretoprovidesufficientheightabovetheroof
to prevent water from entering the unit.
NOTE: This unit was shipped for horizontal installation. Con-
vert to downflow per instructions:
Remove covers from the downflow supply and return air open-
ings and place them over the horizontal supply return air
openings(paintedsideout)andsecurewithsheetmetalscrews.
See Figure 6.
3. Be sure the mounting curb spans structural members (trusses)
oftheroof, thereby providing sufficient supportfor the weightof
the unit, the curb, the duct(s), and any factory or field installed
accessories. See Figures 1, 7, 8, 9, 10, and 11.
4. Be sure the hole in the structure for the ducts is large enough
to accommodate the fabricated ducts and the insulation sur-
rounding them. See Figure 4.
Note: If any internal accessories are to be added to the unit,
install them at the shop if at all practical.
5. These units are design certified for outdoor installation. These
units may be installed directly on wood flooring or on Class A,
Class B, or Class C roof covering material. The discharge air
from the condenser fans must be unrestricted for a minimum of
3 feet above the unit.
The air inlet hood in the combustion blower access panel must
haveadequateclearancearoundairopeningsintothecombus-
tion area. See Outline Drawing, Figure 3. continued on next page

Page 8
LOCATIONS AND RECOMMENDATIONS
15. Access and service clearances for the unit must be given
careful consideration when locating the duct entrance open-
ings. Figure 4 provides unit dimensions.
16. All fabricated outdoor ducts should be as short as possible.
CLEARANCES
1. The recommended clearances for single-unit installations are
illustrated in Figure 4. These minimum requirements are not
only an important consideration when determining unit place-
ment, but they are also essential to ensure adequate service-
ability, maximum capacity, and peak operating efficiency.
2. Any reduction of the unit clearances indicated in these illustra-
tionsmayresultin condenser coil starvation or the recirculation
of warm condenser air. Actual clearances which appear to be
inadequate should be reviewed with a local sales engineer.
IMPORTANT:
1. Remove the Flue and Air Inlet Hood with the gasket from the
return air section of the unit.
Thescrewsthatattachtheflueandairinlethoodwillbeinstalled
in their proper location at the factory. Therefore, they must be
removed and then used to attach the flue and air inlet hood.
2. Remove the packaging material from the components and
secure the Flue and Air Inlet Hood with the gasket to the unit
with sheet metal screws as illustrated in Figure 16 on page 14.
NOTE: Outdoor air or other requirements during heating
operation that result in supply air temperatures below 80
degrees F or return air temperatures below 50 degrees F may
cause flue gas condensate to form and is to be avoided.
INSTALLATION
UNIT SUPPORT
If the unit is to be roof mounted, check the appropriate building
codes for weight distribution requirements. Refer to the applicable
roof curb mounting instruction. Check the unit’s nameplate for
supply voltage required. Determine if adequate electrical power is
available. The furnace may be installed on Class A, B, or C roofing
material.
LOCATION AND CLEARANCES
Installation of the unit should conform to local building codes or, in
the absence of local codes, to the National Fuel Gas Code,
ANSIZ223.1, Latest Revision, and the National Electrical Code.
Canadian installations must conform to CSA and local codes.
Select a location that will permit adequate combustion and ventila-
tion air in accordance with Section 5.3, Air For Combustion and
Ventilation, of the National Fuel Gas Code, ANSIZ223.1, Latest
Revision, or applicable provisions of the local building code.
PLACING AND RIGGING
1. Beforepreparingtheunitforlifting,checktheoutlinedrawingfor
center of gravity for lifting safety. Because of placement of
internalcomponents,theunit’sweightmaybeunevenlydistrib-
uted. Approximate unit weights are given in Figure 2, page 3.
NOTE: Accessory BAYLIFT002AA,akitoffour(4)liftinglugs,is
required for rigging the unit for hoisting. See Figure 7, insert B.
2. Insert the four lifting lugs in the openings provided in the drip lip
ontheperimeteroftheunit. SeeFigure7,insertB. A taporjerk
to the lug will overcome the interference that arises due to the
nipple on the lug.
3. Before hoisting the unit, be sure that the proper method of
rigging is used, with straps or slings and spreader bars for
protectionduringlifting. Alwaystest-lifttheunittodeterminethe
exact unit balance and stability before hoisting it to the installa-
tion location.
continued from page 7
Examine all flue product-carrying areas of the furnace, its vent
system, and the main burner for safe operation. A periodic
inspection of the furnace should be made at the start of each
heating season.
Replacementpartslist for thisGas/ElectricAirConditionermay
be obtained by contacting your local manufacturer representa-
tive.
6. Location of the unit must allow for service clearance around it.
Clearance of the unit must be given careful consideration. See
Figure 4.
7. IMPORTANT: The air outlet duct must have one (1) inch
clearance to combustible material downstream from the
unit.
8. Exhaust vents or other sources of contaminated air should not
be near the unit’s air inlet, if outside air is to be introduced as
make-up air or a ventilation feature is to be used.
9. Check the handling facilities to ensure the safety of personnel
and the unit(s).
10. Caution must be taken at all times to avoid personal
injuries and/or damage to the equipment.
11. The unit must be mounted level for proper drainage of water
through the holes in the base pan.
12. The unit must not be exposed to direct roof water runoff.
13. Flexible duct connectors must be of a flame retardant material.
All duct work outside of the structure must be insulated and
weatherproofed in accordance with local codes.
14. Roof flashing must be installed to seal the roof curb cavity and
must conform to local building codes.

Page 9
INSTALLATION
IMPORTANT: Do not lift the unit without test lifting for
balanceandrigging. Donotlifttheunitinwindyconditions
or above personnel. Do not lift the unit by attaching a
clevis, hooks, pins, or bolts to the unit casing, casing
hardware, corner lugs, angles, tabs, or flanges. Failure to
observe these warnings may result in equipment damage.
4. When the curb and air ducts have been properly installed, the
unit is ready to be hoisted to the roof and set in position.
IMPORTANT: “Spreader Bars” must be used when hoist-
ing the unit.
5. IMPORTANT: The unit must be lowered into position. The
P.V.C. rubber tape on the curb flange permits the unit to be
repositioned if required without destroying the P.V.C. rub-
ber seals affixed to the mounting curb.
PLACING THE UNIT ON A MOUNTING CURB
1. The unit is designed with a perimeter drip lip that is lower that
the unit base bar, see Figure 7, inset A.
2. Position the unit drip lip down over and in contact with the
outside corner of the curb, as illustrated in Figure 8, insert A.
Continue to lower the unit on top of the curb, with the unit drip
lipastraddleandincontactwithboththeendandsiderailofthe
curb. The unit should now rest on top of the curb.
3. Take the two (2) hold-down brackets shipped with the curb and
secure the unit to the curb with hold-down brackets as illus-
trated in Figure 8, insert A.
7
8
SPREADER BARS
OUTDOOR COIL
END OF UNIT
GASKET SEAL
BASE OF UNIT
REST ON TOP OF
CURB RAILS
DRIP LIP
DIMPLE BAYLIFT002A
LIFTING LUGS
SEE DETAIL “A”
“B”
“A”
DRIP LIP ON
PERIMETER OF UNIT
UNIT CORNER
CURB CORNER
EXISTING
SHEET METAL
SCREW
HOLD-DOWN
BRACKET WITH
CURB
FLANGE OF
CURB
“A”
NOTE:
THE INNER PERIMETER OF THE DRIP LIP ON ALL UNITS
SHOULD BE FLUSH WITH THE OUTER PERIMETER OF THE
CURBONTHETWOSIDES SHOWNHERE. SEEFIGURE 2FOR
THE LOCATION OF THE UNIT OVERHANG ON THE
YCY024-060G MODELS.

Page 10
INSTALLATION
ROOFTOP -- UNITS
For roof top applications using a field fabricated frame and ducts,
use the following procedure:
1. The frame must be located and secured by bolting or welding
to the roof. Flashing is required.
2. The hole in the roof must be prepared in advance of installing
the unit.
3. Secure the ducts to the roof.
TYPICAL ROOFTOP APPLICATION WITH FRAME
(YCY024-060G MODELS)
0
TYPICAL ROOFTOP APPLICATION WITH FRAME
(YCY024-060G)
9
4. Place the unit on the frame or roof curb. Refer to Figures 9 or
10.
5. Secure the unit to the frame or roof curb.
6. Insulate any ductwork outside of the structure with at least two
(2) inches of insulation and then weatherproof. There must be
a weatherproof seal where the duct enters the structure.
7. Complete the installation according to the instructions in the
following sections of this manual.
R
OOF FLASHING
WEATHER-PROOF
DUCT
RETURN AIR SUPPLY AIR
ANGLE IRON
FRAME
FLUE
INLET HOO
D
ANGLE IRON
FRAME
SUPPLY AIR
ROOF FLASHING
WEATHER-PROOF
DUCT
RETURN AIR
ROOF FLASHING
FLUE
INLET HOO
D

Page 11
INSTALLATION
GROUND LEVEL -- HORIZONTAL UNITS
Forgroundlevelinstallations,theunitshouldbepositionedonapad
thesizeoftheunitor larger. The unit must be level on the pad. The
padmustnotcomeincontactwiththestructure(SeeFigure11.) Be
sure the outdoor portion of the supply and return air ducts are as
short as possible.
Proceed with the installation as follows:
1. Place the unit on the pad and the five (5) rubber isolators
provided.
CONDENSATE DRAIN PIPING
A3/4-inch female NPT condensatedrainconnection is provided on
the evaporator access panel end of the unit. See Figure 4. Provide
a trap and fill it with water before starting the unit to avoid air from
being drawn through. Follow local codes and standard piping
practiceswhenrunningthedrainline.Pitchthelinedownwardaway
from the unit. Avoid long horizontal runs. See Figure 12.
NOTE: Do not use reducing fittings in the drain lines. The
condensate drain must be:
●Made of 3/4" pipe size.
●Pitched1/4"per foot toprovidefreedrainageto convenient drain
system.
●Trapped.
●Must not be connected to closed drain system.
TYPICAL CONDENSATE DRAIN PIPING
2. Attach the supply and return air ducts to the unit.
3. Insulate any ductwork outside of the structure with at least 2
inchesofinsulationandweatherproof.Theremustbeaweather-
proof seal where the duct enters the structure.
4. Complete the installation according to the instructions in the
following sections of this manual.
3
/
4
" PVC OR COPPER
TUBING AND FITTINGS
1-1/2" MIN.
TYPICAL GROUND LEVEL APPLICATION
(YCY024-060G MODELS)
SIDING
E
XTERIOR
WALL
INSULATE
WEATHERPROOF
OR RAIN SHIELD FLEXIBLE DUCT
CONNECTORS
RETURN AIR
DUCT
SUPPLY AIR
DUCT
OUTDOOR AIR
DISCHARGE
OUTDOOR AI
R
INTAKE
SUPPORT PAD
FOUNDATION
FLUE
INLET HOOD
ISOLATORS
(1 PER CORNER
AND 1 UNDER
UNIT CONTROL BOX)
q
w

Page 12
ATTACHING HORIZONTAL DUCTWORK TO UNIT
Allconditionedairductworkshouldbeinsulatedtominimizeheating
and cooling duct losses. Use a minimum of two (2) inches of
insulation with a vapor barrier. The outside ductwork must be
weatherproofed between the unit and the building.
When attaching ductwork to a horizontal unit, provide a flexible
watertightconnectiontoprevent noise transmission from the unit to
the ducts. The flexible connection must be indoors and made out
of heavy canvas.
NOTE: Donotdrawthe canvas taut between the solid ducts.
DUCTWORK
ATTACHING DOWNFLOW DUCTWORKTOROOFCURB
Supply and return air flanges are provided on the roof curb for easy
duct installation. All ductwork must be run and attached to the curb
before the unit is set into place.
Follow these guidelines for ductwork construction:
Connections to the unit should be made with three-inch canvas
connectors to minimize noise and vibration transmission.
Elbows with turning vanes or splitters are recommended to mini-
mize air noise and resistance.
The first elbow in the ductwork leaving the unit should be no closer
than two feet from the unit, to minimize noise and resistance.
The following warning complies with State of California law, Proposition 65.
WARNING: This product contains
fiberglass wool insulation! Fiberglass dust and ceramic
fibers are believed by the State of California to cause
cancer through inhalation. Glasswool fibers may also
cause respiratory, skin, or eye irritation.
PRECAUTIONARY MEASURES
●Avoid breathing fiberglass dust.
●Use a NIOSH approved dust/mist respirator.
●Avoid contact with the skin or eyes. Wear long-
sleeved, loose-fitting clothing, gloves, and eye
protection.
●Wash clothes separately from other clothing: rinse
washer thoroughly.
●Operations such as sawing, blowing, tear-out, and
spraying may generate fiber concentrations requiring
additional respiratory protection. Use the appropriate
NIOSH approved respirator in these situations.
FIRST AID MEASURES
Eye Contact - Flush eyes with water to remove dust.
If symptoms persist, seek medical
attention.
Skin Contact - Wash affected areas gently with soap
and warm water after handling.
FIELD DUCT
UNIT DUCT
FLANGE
UNIT BASE
AIR PROOF
THIS SEAM
FIELD DUCT
UNIT DUCT
FLANGE UNIT BASE
AIR PROOF
THIS SEAM
FIELD
DUCT UNIT DUCT FLANGE
UNIT BASE
AIR PROOF
THIS SEAM
FIELD DUCT
UNIT DUCT
FLANGE
UNIT BASE
N
OT RECOMMENDED
WATERPROOF SEA
M
WITH BUTYL OR
SILICONE
DOWNFLOW
FIELD DUCT
U
NIT DUCT
FLANGE
UNIT EXTERIO
R
WEATHERPROOF
THIS SEAM
FIELD DUCT
UNIT DUCT FLANGE
UNIT EXTERIOR
WEATHERPROOF
THIS SEAM
FIELD DUCT
U
NIT DUCT
FLANGE
UNIT EXTERIOR
WEATHERPROOF
THIS SEAM
HORIZONTAL

Page 13
IMPORTANT: Before making the gas pipe connection give
serious consideration to providing the required clearance nec-
essary to remove the access panels on the unit
(e.g., economizer and filter access panels).
NOTE:In the absence of local codes, the installation must
conformwithAmericanNationalStandard--Z223.1--NationalFuel
Gas Code, Latest Revision.
The available gas supply must agree with the required gas supply
marked on the unit nameplate. Minimum permissible gas supply
pressure for purpose of input adjustment must be at least 5.0" W.
C. (inches Water Column) for natural gas and 11' W.C. for propane.
PIPE DELIVERY SCHEDULE (NATURAL GAS ONLY)
NOTE: The following procedure and tables below apply to
Natural Gas only.
1.Obtain from the gas company the heating value and specific
gravity of the gas delivered.
2.Determine the exact length of pipe needed.
3.Read the BTUH input nameplate on the furnace.
4.Use the multiplier opposite the specific gravity of the gas given in
Table 1 below and insert in the following formula:
TABLE 1
GAS PIPING INSTALLATION
CFH = Furnace Input in BTUH
Gas Heat Content in BTU/Cu. Ft. X Multiplier
This will give the factor for columns 2 through 6 in Table 2.
5.Using Table 2, select the pipe length nearest to yours.
6.Followthis line verticallydown tothe exactCFHfound in Step 4
above or the next highest value.
7.Read horizontally to the left of this column for the required pipe
size diameter.
TABLE 2
NATURAL GAS ONLY
TABLE OF CUBIC FEET PER HOUR OF GAS
FOR VARIOUS PIPE SIZES AND LENGTHS
PIPE
SIZE
(inch)
LENGTH OF PIPE (feet)
10 20 30 40 50 60 70
1/2 132 92 73 63 56 50 46
3/4 278 190 152 130 115 105 96
1520 350 285 245 215 195 180
1-1/4 1050 730 590 520 440 400 370
THIS TABLE IS BASED ON PRESSURE DROP OF 0.3 INCH W.C. AND 0.6 SP.GR. GAS
NOTE: If this is an propane application, consult your propane
supplier for pipe sizes and deliveries.
GAS PRESSURE SET-UP PRECAUTIONS
IMPORTANT: The furnace and its individual shut-off valve
must be disconnected from the gas supply piping system
duringany pressuretesting ofthatsystem attest pressures
exceeding 1/2 psig (3.48 kPa).
The furnace must be isolated from the gas supply piping system by
closing its individual manual shut-off valve during any pressure
testing of the gas supply piping system at test pressures less than
or equal to 1/2 psig (3.48 kPa).
GAS SUPPLY LINE PRESSURE (ALL FUELS)
Before connecting the unit to the gas supply line, be sure to
determine the gas pressure in the line.
If the gas supply pressure is excessive (above 13.8 inches water
column or 1/2 psig), install a pressure regulator either at the supply
source or in the branch circuit serving the unit. Once the regulator
is installed, set it to provide a maximum pressure of 13.8" W.C. to
thegasvalvefornaturalgaswithaminimumsupplypressureof5.0"
W.C. Maximum supply pressure of 13.8" W.C. to the gas valve for
propane with a minimum pressure of 11.0" W.C.
NOTE: Maximum pressure to the gas valve for natural gas
is 13.8" W.C. Minimum pressure is 5.0" W.C. Maximum
pressureto thegas valveforpropaneis13.8"W.C.Minimum
pressure to the gas valve is 11.0" W.C.
If the supply line pressure is below the minimum supply pressure
indicated on the unit nameplate, contact the gas supply company.
Followthesestepstocompletetheinstallationoftheunitgaspiping.
See Figure 14.
1. Install a tapped, Style A (1/8-inch NPT tap) shut-off gas cock at
the end of the gas supply line near the unit. Be sure the tapped
gas cock is downstream of the pressure regulator, if used.
SPECIFIC
GRAVITY MULTIPIER
MULTIPIERS TO BE USED
WHEN THE SPECIFIC
GRAVITY OF THE GAS IS
OTHER THAN 0.60
.50 1.10
.55 1.04
.60 1.00
.65 .962
DEALER INSTALLED
GROUND UNION
1/8" N.P.T.PLUGGED
ACCESS FOR TEST
GAUGE CONNECTION
FROM
G
AS SUPPLY
DRIP LEG
FIELD SUPPLIED MAIN
GAS VALVE, MUST BE
INSTALLED BY DEALER
OUTSIDE UNIT.
UNIT
TO MAIN
CONTRO
L
VALVE
6"
MIN
r
▲WARNING: NEVER USE AN OPEN FLAME
TO TEST FOR GAS LEAKS: AN EXPLOSION COULD
OCCUR, CAUSING INJURY OR DEATH.

Page 14
FLUE AND HOOD ILLUSTRATION
C66439
9
C664399
y
GAS PIPING INSTALLATION
BURNER & VALVE ILLUSTRATION
t
NOTE: The shut-off gas cock must be installed outside of
the unit and should meet the specifications of all appli-
cable national and local codes.
2.Installagroundunionjointdownstreamoftheshut-offcock.
This joint must also be installed outside of the unit.
3.Install a drip leg at least six (6) inches in depth next to the
union as shown in Figure 14. This drip leg is required to
collect any sediment that may be deposited in the line.
4.Beforeconnectingthepiping circuit to the unit, bleed theair
from the supply line. Then cap or plug the line and test the
pressureatthetappedshut-offcock. Thepressurereading
should not exceed 13.8 inches water column.
5.Using an appropriate backup wrench on the gas valve inlet
boss, connect the gas piping to the unit. Check the
completed piping for leaks using a soap and water solution
or the equivalent.
6.After installation of the gas pipe in the unit, the pipe chase
opening should be closed with the filler/barrier plug pro-
vided.
MANIFOLD PRESSURE
Check the manifold pressure at the unit gas valve. Do not
exceedthe recommended pressure shown onthe unit name-
plate.

Page 15
INPUT CHECK AND ADJUSTMENT
1. Make sure all gas appliances are off except the furnace.
2. Clock the gas meter with the furnace operating (determine the
dial rating of the meter) for one revolution.
3. Match the “Sec” column in the gas flow (in cfh) Table 3 with the
time clocked.
4. Read the “Flow” column opposite the number of seconds
clocked.
5. Use the following factors if necessary.
For 1 Cu. Ft. Dial Gas Flow CFH =
Chart Flow Reading / 2
For 1/2 Cu Ft. Dial Gas Flow CFH =
Chart Flow Reading / 4
For 5 Cu. Ft. Dial Gas Flow CFH =
10X Chart Flow Reading / 4
6. Multiply the final figure by the heating value of the gas obtained
from the utility company and compare to the nameplate rating.
This must not exceed the nameplate rating.
7. Changes can be made by adjusting the manifold pressure.
a. Attach a manifold pressure gauge.
b. Remove the slot screw on top of the gas valve for 1st stage
manifold pressure adjustment. Remove slot screw on outlet
side for 2nd stage adjustment (See Figure 17).
c. Turn the adjustment nut in to increase the gas flow rate, and
out to decrease the gas flow rate using a 3/32" hex wrench.
GAS PIPING INSTALLATION
GAS FLOW IN CUBIC FEET PER HOUR
2 CUBIC FOOT DIAL
Sec. Flow Sec. Flow Sec. Flow Sec. Flow
8 900 29 248 50 144 82 88
9 800 30 240 51 141 84 86
10 720 31 232 52 138 86 84
11 655 32 225 53 136 88 82
12 600 33 218 54 133 90 80
13 555 34 212 55 131 92 78
14 514 35 206 56 129 94 76
15 480 36 200 57 126 96 75
16 450 37 195 58 124 98 73
17 424 38 189 59 122 100 72
18 400 39 185 60 120 104 69
19 379 40 180 62 116 108 67
20 360 41 176 64 112 112 64
21 343 42 172 66 109 116 62
22 327 43 167 68 106 120 60
23 313 44 164 70 103 124 58
24 300 45 160 72 100 128 56
25 288 46 157 74 97 132 54
26 277 47 153 76 95 136 53
27 267 48 150 78 92 140 51
28 257 49 147 80 90 144 50
HIGH ALTITUDE INSTALLATION
Unitnameplateratingsare based on equipment operation from sea
level to 2000 feet elevation above sea level. If the unit installation
isfrom2000-4500feetelevation, itwillbenecessarytochangethe
burnerorificestothenotedsizes,(ref.National Fuel Gas Code, sec
8.1.2, Appendix F, Table F4).
SAG EPYT SSERP.NAM ).C.W.ni( EZISECIFIRO tf0002-0 EZISECIFIRO tf0054-0002
LARUTAN3.3 24 *34
ENAPORP0.014555
*DEPPIHSYROTCAF
TABLE 3
Switch Toggles
"ON" or "OFF"
2nd Stage (Hi)
Manifold
Pressure
Adjustment
1st Stage (Lo)
Manifold
Pressure
Adjustment
u

Page 16
ELECTRICAL CONNECTIONS
Electricalwiringandgroundingmustbeinstalledinaccordancewith
local codes or, in the absence of local codes, with the National
Electrical Code ANSI/NFPA 70, Latest Revision.
ELECTRICAL POWER
It is important that proper electrical power be available for the unit.
Voltagevariationshouldremainwithinthelimitsstampedontheunit
nameplate.
DISCONNECT SWITCH
Provide an approved weatherproof disconnect either on the side of
the unit or within close proximity and within sight of the unit.
OVER CURRENT PROTECTION
The branch circuit feeding the unit must be protected as shown on
the unit rating plate.
POWER WIRING
The power supply lines must be run in weathertight conduit to the
disconnectandintothebottomoftheunitcontrolbox. Providestrain
relief for all conduit with suitable connectors.
Provide flexible conduit supports whenever vibration transmission
may cause a noise problem within the building structure.
Be sure all connections are made tight. See Figure 18.
NOTES: For branch circuit wiring (main power supply to unit
disconnect),wiresizeforthelengthofrunshouldbedetermined
using the circuit ampacity found on the unit nameplate and the
N.E.C.
For more than 3 conductors in a raceway or cable, see the
N.E.C. for derating the ampacity of each conductor.
GROUNDING: THEUNITMUSTBEELECTRICALLYGROUNDED
IN ACCORDANCE WITH LOCAL CODES OR THE NATIONAL
ELECTRIC CODE.
ELECTRICAL WIRING
FILTER INSTALLATION
AIR FILTERS
Filters are to be used with the YCY024-060G heating/cooling units.
The basic unit does not have filters in it. However, a filter frame
accessory is offered that will allow filters to be installed within the
unit.
Otherwise a filter rack must be installed by the installer in the duct
work.
Affix the filter label supplied with the unit adjacent to the filter area.
TABLE 4
UNIT NOMINAL
CFM FILTER* (Sq Ft) SIZE FILTER RESISTANC
E
YCY024F 800 2.67 0.05
YCY030F 1000 3.33 0.05
YCY036F 1200 4.00 0.05
YCY042F 1400 4.67 0.05
YCY048F 1600 5.33 0.05
YCY060F 2000 6.67 0.05
*Filters must be installed in the return air system. The above square
footagesarebased on300F.P.M.facevelocity. Ifpermanentfiltersare
used,size per mfg.recommendationwith clearresistanceof 0.05"WC.
THERMOSTAT HEAT ANTICIPATOR
Thethermostat heat anticipators should beset to.4 amps onsingle
or two stage thermostats.
IMPORTANT: Upon completion of wiring check all electrical
connections, including factory wiring within the unit, make
sureallconnectionsaretight. Replaceandsecureall electrical box
covers and access doors before leaving the unit or turning on the
power to the unit.
NOTE: Unit must be grounded for ignitor to operate prop-
erly. Gas pipe to unit is not an adequate ground. Ground
the unit internally as provided. See wiring diagram for
location.
CONTROL WIRING (CLASS II)
Low voltage control wiring should not be run in conduit with power
wiring unless Class 1 wire of proper voltage rating is used. Route
the thermostat cable or equivalent single leads of No. 18 AWG
colored wire from the thermostat subbase terminals through the
rubber gromment on the unit. See Figures 3 and 4 for the control
entry location. Make connections as shown on the unit wiring
diagram and in Figure 18.
Do not short thermostat wires since this will damage the control
transformer.
Recommendedwire sizesandlengthsfor installingtheunitthermo-
stat are provided in Table 5. The total resistance of these low
voltage wires must not exceed one (1) ohm. Any resistance in
excess of 1 ohm may cause the control to malfunction because of
the excessive voltage drop.
WIRE SIZE MAXIMUM LENTGH (Ft)
18 75
16 125
14 200
TABLE 5
THERMOSTAT WIRE SIZE AND MAXIMUM LENGTH

Page 17
YCY-G FIELD WIRING DIAGRAM
the Thermostat System Switch until power has been applied long
enough to evaporate any liquid R-22 in the compressor. It is
recommendedthatthesumpheaterbeenergizedforeight(8)hours
prior to starting.
After all electrical wiring is complete, set the thermostat system
switch in the OFF position so that the compressor will not run
and then apply power by closing the system main disconnect
switch.Thiswillactivatethecompressorsumpheat. Donotchange
ELECTRICAL WIRING
C 757192
i

Page 18
START - UP
PRE-START QUICK CHECKLIST
●Is the unit properly located and level with the proper clearance?
See Figure 4.
●Is the duct work correctly sized, run, taped, insulated, and
weatherproofed with proper unit arrangement? See Ductwork
Installation section.
●Isthegas piping correctly sized, run, trapped, andpurged of air?
See Gas Piping section.
●Isthecondensatelineproperlysized,run,trapped,andpitched?
●Isthefilterofthecorrectsizeandnumber? Isitcleanandinplace?
●Is the wiring properly sized and run according to the unit wiring
diagram?
●Are all the wiring connections, including those in the unit, tight?
●Has the unit been properly grounded and fused with the recom-
mended fuse size? See Wiring Data.
●Is the thermostat level, correctly wired, well located, and set for
the proper heat anticipation?
●Have the air conditioning systems been checked at the service
ports for charge and leak tested if necessary?
●Does the condenser fan and indoor blower turn free without
rubbing, and are they tight on the shafts?
●Has the indoor blower speed been determined and the proper
speed been set? See the Unit Wiring Diagram.
●Has all work been done in accordance with applicable local and
national codes?
●Are all covers and access panels in place to prevent air loss and
safety hazards?
STARTING THE UNIT IN THE COOLING MODE
CAUTION: Before starting the system on the cooling cycle, turn the
thermostat switch to OFF and close the unit disconnect switch. This
procedure energizes the compressor crankcase heater, vaporizing
any liquid refrigerant in the crankcase. This is a precaution against
foaming at startup which could damage the compressor bearings.
Allow the heater to operate a minimum of eight (8) hours.
NOTE: See the section on “Sequence of Operation” for a
description of the cooling operating sequence.
To start the unit in the cooling mode, set the thermostat system
switch to COOL and move the thermostat COOL indicator to a
setting below room temperature. The condenser (outdoor) fan
motor compressor and evaporator (indoor) fan motor will operate
automatically.
OPERATING PRESSURES
After the unit has operated in the cooling mode for a short period of
time, install pressure gauges on the gauge ports of the discharge
andsuctionlinevalves. Checkthesuctionanddischargepressures
and compare them to the normal operating pressures provided in
the unit’s SERVICE FACTS.
NOTE: Donotusethepressuresfromtheunit'sSERVICEFACTS
to determine the unit refrigerant charge. The correct charge is
shown on the unit nameplate. To charge the system accurately,
weigh in the charge according to the unit nameplate.
VOLTAGE
With the compressor operating, check the line voltage at the unit.
The voltage should be within the range shown on the unit name-
plate. Iflowvoltageisencountered,checkthesizeandlengthofthe
supply line from the main disconnect to the unit. The line may be
undersized for the length of the run.
COOLING SHUT DOWN
Placethesystemselector in the OFFpositionorresetthermostatat
a setting above room temperature.
Do not de-energize the main power disconnect except when unit is
to be serviced. Power is required to keep the heat pump compres-
sor warm and boil off refrigerant in the compressor.
HEATING CYCLE
NOTE: See Sequence of Heating Operation.
These units are equipped with a solid-state ignition control that
lights the burners each time the thermostat calls for heat. The
burners are extinguished during the OFF cycle.
Thegasheatingsectionoftheunitcanbestartedusingthefollowing
procedure:
1. Be sure the thermostat is at its lowest setting and the power to
the unit is off.
a. Turn the main shutoff valve on the gas supply line ON.
b. Turn or switch the manual valve on the combination gas
valve ON position.
2. Be sure the burner compartment access panel is in place.
a. Turn on the electrical power to the unit.
b. Turn the thermostat to the highest setting in the heating
cycle.
3. As the thermostat calls for heat, the system cycles as follows:
a. The combustion blower is energized.
b. The pressure switch is closed.
c. The gas valve opens and the ignitor lights the burner.
d. Cycle the thermostat on and off a few times to check out the
control system and burner operation characteristics.
4. With the burners operating, check the manifold pressure with a
manometer. Do not exceed recommended pressures.
5. Adjust the unit to obtain an air temperature rise with that
specified on the unit nameplate.
6. NOTE: For manifold pressures and orifice sizes for gas with
other BTU ratings, contact the local gas utility. Manifold
pressureshouldbe3.5incheswatercolumn (+0.1). Inputmust
not exceed the value shown on the rating plate.
7. Settheheatanticipatorofthethermostattoequaltheamperage
draw of the gas valve, approximately 0.7.

Page 19
FINAL INSTALLATION CHECKLIST
START - UP
8. Set the thermostat at the desired temperature setting and the
unit will function automatically.
STARTING THE UNIT IN THE GAS HEATING MODE
1. Checktomakesureallgrillesandregistersareopenandallunit
access doors are closed before start-up.
2. Purge the gas supply line of air by opening the union ahead of
the unit. When the odor of gas is detected, retighten the union
and wait five (5) minutes before proceeding.
3. Set the wall thermostat to its lowest position and place the fan
switch in the AUTO or ON position.
4. Open the main gas valve(s) and turn on the unit power supply.
5. Reset the heating temperature lever on the room thermostat at
the highest value above room temperature. The combustion
blower motor should energize. The main burners should light
within 20-25 seconds. Initial start may be delayed somewhat if
the unit has not been purged and air is trapped in the gas line.
NOTE: Bluesmokeproducedbytheheatexchangerduringthe
initial burner firing is caused by a thin film of oil on the surface
of the heat exchanger. This oil will burn off quickly.
6. Cycle the thermostat OFF and ON a few times at a rate of not
more than once every thirty (30) seconds. Check both the
control operation and the burner operating conditions.
MANIFOLD PRESSURE
1. Connect a manometer to the pressure tap at the outlet side of
the unit’s gas valve. Read the manifold pressure with the main
burners firing.
2. If the manifold pressure reading does not match the value
indicated on the unit nameplate, the unit pressure regulator
must be adjusted as follows:
a. Removethe cover screw on thegas regulator locatedon the
front side of the unit’s gas valve.
b. Turn the adjusting screw clockwise to increase manifold
pressure or counterclockwise to decrease manifold pres-
sure.
3. Check the temperature rise during furnace operation to insure
that it falls within the range specified on the unit nameplate.
4. If the temperature rise noted is outside of the specified limits,
adjust the indoor air flow to cause the temperature rise of the
heat exchanger to fall within the required range.
●Does the unit run and operate as described in the section on
“Sequence of Operation” in response to the room thermostat?
●Arethecondenserfanandindoorbloweroperatingcorrectlywith
proper rotation and without undue noise?
●Is the compressor operating correctly and has the system been
checked with a charging chart?
●Has the voltage and running current been checked to determine
if it is within limits?
●Has the thermostat been checked for calibration and the air
discharge grilles adjusted to balance the system?
●Hasthe ductwork been checked forair leaks andcondensation?
●Has the furnace manifold pressure been checked and adjusted
if necessary?
●Has the heating air temperature rise been checked?
●Has the unit been checked for tubing and sheet metal rattles?
Are there any other unusual noises to be checked?
●Are all covers and panels in place and properly fastened?
●Hastheownerormaintenancepersonnelbeengiventhismanual
and the warranty? Has the owner or maintenance been in-
structed on proper operation and maintenance of this unit?
IGN LED DIAGNOSTIC INDICATOR
FLASHING SLOW NORMAL CALL FOR HEAT
CONTINUOUS ON NORMAL
CONTINUOUS OFF CHECK POWER / INTERNAL FAILURE
2 FLASHES SYSTEM LOCKOUT ( NO FLAME )
3 FLASHES PRESSURE SWITCH PROBLEM
4 FLASHES HIGH LIMIT (TCO) OPEN
5 FLASHES FLAME SENSED WITH GAS VALVE OFF
6 FLASHES FLAME ROLLOUT SWITCH (FL) OPEN
7 FLASHES W1 & W2 SWAPPED

Page 20
SEQUENCE OF OPERATION
Operationoftheunitheatingorcoolingcyclesiscontrolledbythe
setting of the system switch on the room thermostat. Once the
systemswitchisplacedeitherinthe“HEAT”or“COOL”position,
unit operation is automatic. A fan switch on the thermostat also
provides for it continuous operation of the evaporator fan when
desired. The fan switch “ON” position provides continuous
operation while the “AUTO” position provides operation during
the heating or cooling cycles.
HEATING CYCLE
Thermostat call for heat (2-stage thermostat)
Call for 1st stage only:
(R) and (W1) thermostat contacts close signaling the control
module (IGN) to run its self-check routine. After the control has
verifiedthatthepressureswitch(PS)contactsareopen,thelimit
switch (TCO) contacts are closed, and the flame rollout (FL)
switch is closed, the induced draft blower (CBM) will be ener-
gized on high speed for approximately 5 seconds.
Aftertheinduced draftblower (CBM)hascomeupto speed,the
control will verify that the pressure switch (PS) contacts are
closed and switch the induced draft blower to low speed for 10
second prepurge. The gas valve (GV) is energized in the first
stage to permit gas flow and the spark ignitor (IP) is energized.
Theflamedetector(FD)confirmsthatignitionhasbeenachieved
within the 7 second trial period.
As the flame detector confirms that ignition has been achieved
the delay to indoor fan on period begins timing and after
approximately45seconds,theindoorblowermotor(IDM)willbe
energized at low speed and will continue to run during the
heating cycle.
Call for 2nd stage after 1st stage:
(R) and (W2) thermostat contacts close signaling a call for
secondstageheat.Theinduced draft motor(CBM) is energized
on high speed and the gas valve on second stage. After
approximately 30 seconds the control energizes the indoor
blower on high speed.
2nd stage satisfied, 1st stage still called:
(R) and (W2) opens, the induced draft blower is reduced to low
speed the gas valve is reduced to first stage. After aprox. 30
seconds the indoor blower motor is reduced to low speed.
1st stage satisfied:
(R) and (W1) opens, the gas valve (GV) will close. The induced
draft blower (CBM) will be de-energized after approximately 5
secondspostpurge.Theindoorblowermotor(IDM)willcontinue
torunforthefanoffperiod(fieldselectable60or90seconds[by
dip switch]), then will be de-energized by the control module.
Thermostat call for heat (1-stage Thermostat)
(R) and (W1/W2) (jumpered) thermostat contacts close signal-
ing a call for heat. 1st stage sequence of operation remains the
same as above. 2nd stage heat has a 10 minute delay from the
time of 1st stage ignition.
Thermostat satisfied:
(R)and(W1/W2)(jumpered)contactsopensignalingthecontrol
moduletoclosethegasvalveandde-energizetheinduceddraft
blowerafterapproximately5secondspostpurge.TheI.D.blower
motor will continue to operate at the current speed for 60 or 90
seconds after the flames are extinguished .
SAFETY SEQUENCES
This product is equipped with safety devices to protect against
abnormal conditions.
The temperature limit switch (TCO) is located in the gas com-
partmentonthevestibulepanelabovetheburnerassembly.This
automatic reset device protects against excessive leaving air
temperature. If this device opens, the gas valve is immediately
closed and will not permit operation until the limit switch closes.
The rollout switch (FS) is located in the gas compartment near
the inlet of the burners. This is a single use device designed to
protectagainstany formof flamerollout. Ifthisdeviceis opened
thegasvalveisimmediatelyde-energizedandthecontrol(IGN)
willlockoutthesystem.Therolloutswitch(FS)mustbereplaced
before operation is allowed to continue.
Thepressureswitch(PS) islocated inthe upperright sideof the
gas compartment. This automatic device assures adequate
combustion air pressure. If pressure against the induced draft
bloweroutlet becomesexcessive,the pressureswitchwill react
andshutoffthegasvalve,untilacceptablecombustionpressure
is again available.
If the control (IGN) does not sense flame within the first trial for
ignition period, the gas valve will be de-energized. The control
(IGN) will initiate a 60 seconds interpurge. Following the
interpurge,onthesecondtrialthegasvalvewillbeenergizedon
second stage (high heat input). If the flame is sensed within 10
secondsafterthesecond tryand only acall forfirst stageexists,
the gas valve will be reduced to first stage. If the second try is
not successful, the control will start other 60 second interpurge.
After the interpurge, a third attempt will be tried. The gas valve
will be energized on second stage (high heat input). If the flame
is sensed within 10 seconds after the third try and only a call for
first stage exists, the gas valve will be reduced to first stage. If
the third try is not successful, the control will lock out.
If loss of flame occurs during a heating cycle, the control (IGN)
will close the gas valve and cycle through the ignition trial as
stated above.
If control lock out occurs, the control (IGN) will retry a complete
ignition sequence in 2 hours
The control (IGN) can be reset by removing power to the unit or
by turning the thermostat from “on” to “off" for approximately
three seconds, then back “on.”
COOLING CYCLE
With the room thermostat system switch in the “COOLING”
position and the fan switch in the “AUTO” position, the com-
pressor contactor (CC) and the G-IGN are energized.
Theenergizedcompressorcontactor(CC)completesthecircuit
to the compressor (CPR) and a secondary circuit to the outdoor
fan motor (ODM). If the compressor safety controls are closed,
the compressor (CPR) will operate with the outdoor fan motor
(ODM).Theindoorfanmotor(IDM)willoperate.Thethermostat
will continue to cycle the compressor and fans to maintain the
desired temperature.
Withthethermostatfanswitchinthe“ON”position,theindoorfan
motor (IDM) will continue to run regardless of compressor and
condenser fan operation.
ICM FAN MOTOR ADJUSTMENTS
Iftheairflowneedstobeincreasedordecreased,seetheIndoor
BlowerPerformanceTableintheServiceFacts.. Informationon
changing the dip switch settings for speed control of the blower
motor is in this table.
Blower speed changes are made on the ICM Fan Control
mounted in the control box. The ICM Fan Control controls the
variable speed motor.
Thereis abankof 8dip switches (SeeFigure 19), locatedat the
upper left side of the board. The dip switches work in pairs to
select the cooling/heat airflow (CFM/TON), and Fan off-delay
options.