Single-Package Rooftop Heat PumpUnit with the Following InnovativeStandard Features:• Cycle-LOC™ compressor anticycleprotection

• Chronotemp™ defrost controls• high- and low-pressure cutoutswitches and freeze protectionthermostat

• suction line accumulators on eachindependent circuit

• two-in. return-air filters• refrigerant filter driers• galvanized steel cabinet with pre-painted protection on allexternally-exposed surfaces

• single power entry to unit

Features/BenefitsCompact, vertical discharge unitseasily convert to horizontal discharge,combining installation flexibility withefficient performance and easymaintenance.

Easy maintenance andconversionAll units are factory shipped in thevertical discharge configuration forfit-up to standard roof curbs, but canbe easily converted to horizontaldischarge with the use of one of thehorizontal supply/return curbs oradapter.Compact and self contained, the

unit is readily transported, rigged, andinstalled. Prepunched lifting holesand factory-supplied lifting hardwaremake the rigging job easier still.The terminal board located in the

base unit control box allows easy con-nection to room thermostat, out-door thermostat(s), economizer, andelectric heat. Self-supporting pan-els allow quick removal for easyservicing.

ProductData

50PQSingle-Package Rooftop

Heat Pump Units50 Hz

Nominal 52.8 kW (15 Tons)

Copyright 1995 Carrier Corporation Form 50PQ-C1PD

The convenient slide-in filter trackholds 51 mm (2-in.) filters, permittingeasy maintenance.

Efficient operation, depend-able performanceBuilt with energy efficiency in mind,the 50PQ cooling coils use coppertubing and mechanically bonded alu-minum plate fins. All coils arecompletely degreased at the factory toeliminate coil blowoff problems.The 50PQ016 unit features two

rugged semi-hermetic compressorswith positive lubrication, vibration iso-lators, crankcase heater, and reli-able, internal motor protection.Two independent refrigerant and

electrical circuits, each with its owncompressor, reversing valve, expansiondevice, coil circuit, and Cycle-LOC™device protection, improve part-loadefficiency and reduce operating costswhile providing standby reliability.Special check valves and capillary

tube refrigerant metering provideimproved heat transfer for the bestperformance possible during bothheating and cooling modes.The patented Chronotemp™ defrost

system uses time and temperature tokeep the outdoor coil frost-free foreconomical, dependable cooling opera-tion at temperatures down to 4.4 C(40 F) as shipped from the factory.Accessory Motormastert head pressurecontrol permits unit operation in cool-ing at outdoor ambient temperaturesdown to −29 C (−20 F).Refrigerant circuit protection as-

sures dependability. Loss-of-charge/low-pressure cutout protection allowsoperation at lower ambient condi-tions while protecting againstlow-charge operation. Freeze protec-tion thermostat protects against in-door coil frost buildup. High-pressureswitch protects against above nor-mal operating pressure. Replaceablefilter driers trap moisture and dirt.Capillary tube refrigerant meteringprecisely controls refrigerant flow,preventing slugging and floodback,while maintaining optimum unitperformance.Units equipped with economizer

have a thermostatically controlled,fully modulating damper which admitsup to 100% outdoor air and pro-vides low-cost cooling. Dry bulb ther-mostat governs economizer cooling

changeover to provide lowest costoperation in mild weather.Belt-driven indoor-air fans provide

quiet and efficient operation. The belt-driven indoor-fan motor allows avail-able static pressure to be adjustedto meet job requirements. In addition,indoor fans are capable of movingample air quantities and achievinghigh external static pressures suitablefor the most demanding applications.Direct-drive outdoor-air fans are fac-

tory lubricated and positioned forquiet, efficient vertical discharge.Carrier-specified semi-hermetic com-

pressors are equipped with crankcaseheaters and internal linebreak forprotection against overcurrent andover-temperature conditions, as wellas Cycle-LOC™ compressor

protection. If any safety device trips,Cycle-LOC compressor protectionprevents short cycling by shutting offthe compressor until the Cycle-LOCprotection mechanism is reset.Compressor restart is accomplished atthe space thermostat.The crankcase heater prevents

refrigerant dilution of oil during offcycles, ensuring proper lubrication atall times and prolonging compres-sor life.The weather-resistant cabinet is

designed for durability under all climaticconditions. The unit cabinet is madeof Carrier Weather Armort galvanizedsteel, which is bonderized and pre-painted for long life and attractiveappearance, and provides protectionon all externally exposed surfaces.

Table of contentsPage

Features/Benefits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1,2Model Number Nomenclature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2Physical Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3Standard Capacity Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4Options and Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4,5Base Unit Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6Accessory Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7,8Selection Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9,10Performance Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11-15Electrical Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16Typical Piping and Wiring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16Typical Wiring Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18Application Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19,20Guide Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21-23

Model number nomenclature

2

Physical data — SIOPERATING WEIGHT (Kg)Base Unit 795Unit with Economizer 864Roof Curb 91

COMPRESSORQuantity...Type 2...06DA8180Oil (L) 2.6 (each)

REFRIGERANT (Capillary Control) R-22Charge (Kg)System 1 7.65System 2 7.65

OUTDOOR COIL Copper Tubes, Aluminum FinsRows 3Fins/m 550Total Face Area (m 2) 2.06

OUTDOOR AIR FAN Propeller Type, Direct DriveNominal Airflow (L/s) 4760Quantity...Diameter (mm) 2...660Motor (kW) 0.75

INDOOR COIL Copper Tubes, Aluminum FinsRows 3Total Face Area (m 2) 1.7

INDOOR AIR FAN Centrifugal, Adjustable, Belt DrivenQuantity...Size (mm) 2...254 x 254Nominal Airflow (L/s) 2450Speed Range (r/s) 15.9-20.6Maximum Allowable Speed (r/s) 24.15Fan Pulley Pitch Diameter (mm) 132Speed Change per Full Turn ofMovable Pulley Flange (r/s) 0.87

Movable Pulley Max Full Turnsfrom Closed Position 5.4

Factory Speed Setting (r/s) 19.0INDOOR AIR FILTER, Type Fiberglass

Quantity...Size (mm) 4...508 x 508 x 504...406 x 508 x 50

NOTE: System 1 consists of upper portion of outdoor coil and lower portion of indoor coil, andSystem 2 consists of upper portion of the indoor coil and lower portion of outdoor coil.

Physical data — EnglishOPERATING WEIGHT (lb)Base Unit 1750Unit with Economizer 1900Roof Curb 200

COMPRESSORQuantity...Type 2...06DA8180Oil (oz) 88 (each)

REFRIGERANT (Capillary Control) R-22Charge (lb)System 1 16.8System 2 16.8

OUTDOOR COIL Copper Tubes, Aluminum FinsRows 3Fins/in. 14Total Face Area (sq ft) 22.2

OUTDOOR AIR FAN Propeller Type, Direct DriveNominal Airflow (Cfm) 10,100Quantity...Diameter (in.) 2...26Motor (Hp) 1.0

INDOOR COIL Copper Tubes, Aluminum FinsRows 3Total Face Area (sq ft) 18.3

INDOOR AIR FAN Centrifugal, Adjustable, Belt DrivenQuantity...Size (in.) 2...10 x 10Nominal Airflow (Cfm) 5200Speed Range (rpm) 953-1234Maximum Allowable Speed (rpm) 1450Fan Pulley Pitch Diameter (in.) 5.2Speed Change per Full Turn ofMovable Pulley Flange (rpm) 52

Movable Pulley Max Full Turnsfrom Closed Position 5.4

Factory Speed Setting (rpm) 1140INDOOR AIR FILTER, Type Fiberglass

Quantity...Size (in.) 4...20 x 20 x 24...16 x 20 x 2

NOTE: System 1 consists of upper portion of outdoor coil and lower portion of indoor coil, andSystem 2 consists of upper portion of the indoor coil and lower portion of outdoor coil.

3

Standard capacity ratings — SI and English

STANDARDAIRFLOW

COOLING HIGH-TEMPERATURE HEATING LOW-TEMPERATURE HEATING

Capacity PowerInput(kW)

Capacity PowerInput(kW)

COPCapacity Power

Input(kW)

COPL/s Cfm kW 1000 Btuh kW 1000 Btuh kW 1000 Btuh

2450 5200 45.1 154,000 14.8 43.7 149,000 12.4 3.5 23.2 79,000 9.8 2.4

COP — Coefficient of PerformanceNOTE: Standard ratings are net values, reflecting the effects of circu-lating fan motor power and heat.Cooling Standard: 26.7 C (80 F) db, 19.4 C (67 F) wb indoor enteringair temperature and 35 C (95 F) db air entering outdoor unit.

High-Temperature Heating Standard: 21.2 C (70 F) indoor enteringair temperature and 8.3 C (47 F) db, 6.1 C (43 F) wb air entering out-door unit.Low-Temperature Heating Standard: 21.1 C (70 F) indoor entering airtemperature and −8.3 C (17 F) db, −9.4 C (15 F) wb air entering outdoorunit.

Options and accessoriesITEM OPTION* ACCESSORY†Integrated Economizer X XElectric Heater X XEmergency Heat Package and Relays XRoof Curbs (Vertical and Horizontal) XHorizontal Adapter XRemote Control Panel XThermostat and Subbase XTime Guard T Control Device XPower Exhaust XTwo-Position Damper XBarometric Relief Damper XMotormaster T Head Pressure Control XGlycol Coil X

*Factory Installed.†Field Installed.

HEAD PRESSURE CONTROLThe 50PQ016 standard units are designed to operate at out-door temperatures down to 1.7 C (35 F). With accessory Motor-master control (condenser-fan speed modulation), units canoperate at outdoor temperatures down to −29 C (−20 F). Thehead pressure control, which mounts in the outdoor-air section,modulates the outdoor-fan motor to maintain correct condens-ing temperature. Refer to price pages for more details, or con-tact your local Carrier representative.

THERMOSTAT

Zone thermostat (24 v) provides one- or 2-stage cool-ing for control of unit. Matching subbases are availablewith or without tamperproof switches and automaticchangeover.

GLYCOL COIL

Glycol coil is intended for add-on type applications or new work wherea boiler system is available. Glycol coil and electric heat cannot beinstalled together.NOTE: Dimensions in ( ) are in millimeters.

4

ELECTRIC HEATER

Available either as a factory-installed option or for field instal-lation with high-temperature limit switches and overcurrentprotection.Nominal heating capacity of this heater is 36 kW. An emer-

gency heat subbase and relay are included to allow the com-pressor to be switched off manually and electric heat to beswitched on manually if the system malfunctions. This featurecan also be used for quick morning warm-up or to lock outcompressor.

POWER EXHAUST

When used with accessory/optional economizer, power exhaust helpsto relieve building overpressurization.

5

Base unit dimensions

NOTES:1. Space required for service clearance and airflow: Allow 1.8 m (68-09) above the unit; 2.1 m (78-09) on filter access

panel end; and 1.2 m (48-09) on remaining sides of unit.2. Dimensions in ( ) are in millimeters.

6

Accessory dimensions

ROOF CURBS AND HORIZONTAL ADAPTER

ACCESSORYPACKAGE NO.

CURBHEIGHT DESCRIPTION ‘‘A’’ ‘‘B’’ ‘‘C’’

50PQ900221 18-29 (305) Standard Curb — 149 High — — —

50PQ900141 28-09 (610) Standard Curb for UnitsRequiring High Installation — — —

50PQ900151 28-09 (610) Horizontal Supplyand Return Curb 58-69 (1676) 08-21⁄29 (64) 18-69 (457)

50DP900211 18-119 (584) Pre-Assembled, High-Static,Horizontal Adapter 68-29 (1880) 08-61⁄49 (159) 18-25⁄89 (371)

NOTE: To prevent the hazard of stagnant water build-up inthe drain pan of the indoor-air section, unit can only be pitchedas shown.

LEGENDCOMP SECT. — Compressor Section

NOTES:1. Roof curb accessory is shipped unassembled.2. Insulated panels, 1⁄2-in. thick neoprene-coated, 2 lb

density.3. Dimensions in ( ) are in millimeters.

4. Direction of airflow.

5. Roof curb: 18 gage steel.6. Attach all ductwork to roof curb.

7

Accessory dimensions (cont)

HORIZONTAL SUPPLY/RETURN ADAPTER

NOTES:1. The 50DP900211 is a fully factory preassembled horizontal

adapter which includes an insulated high static regain transi-tion duct to substantially improve fan static performance.

2. Dimensions in ( ) are in millimeters.

ACCESSORY REMOTE CONTROL PACKAGE(Accessory Remote Control Panel and Accessory Thermostat Shown)

NOTE: Dimensions in ( ) are in millimeters.

8

Selection procedure — SI

I Determine job requirements.Estimated cooling requirements:Cooling loadTotal Capacity (TC) . . . . . . . . . . . . . . . . . . . . . . 40 kWSensible Capacity (SHC) . . . . . . . . . . . . . . . . . . 30 kWOutdoor-Air Temperature (OAT) . . . . . . . . . . . . . 36 CTemperature of Air Entering Indoor CoilDry-bulb (Edb) . . . . . . . . . . . . . . . . . . . . . . . . . . 27 CWet-bulb (Ewb) . . . . . . . . . . . . . . . . . . . . . . . . . . 20 C

Air Quantity (flow rate) . . . . . . . . . . . . . . . . . 2500 L/sExternal Static Pressure (ESP)(loss in ducts and diffuser) . . . . . . . . . . . . . . 0.20 kPaEstimated heating requirements:Heating load . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35 kWat Winter Design Temperature . . . . . . . . . . . . −8 C

Temperature of Air Entering Indoor Coil . . . . . 21 CPower Supply . . . . . . . . . . . . . . . . . . . . . . . . 400-3-50Options: Economizer, Electric Heat.

II Determine unit size.Select unit on cooling capacity required.Enter cooling capacity table at required air quantity(2500 L/s) and indoor coil entering wet-bulb tempera-ture (20 C). Read down table for gross total capacity(TC) and gross sensible capacity (SHC) opposite thecondenser entering air temperature (36 C).Read a TC of 46 kW and SHC of 33.4 kW. Unit powerrequirements is 15.2 kW. (These gross capacities mustbe adjusted for the effects of indoor fan motor heat andthe sensible heat capacity needs to be further adjustedfor dry-bulb temperature other than 26.7 C. See sec-tions IV and V.) To correct gross sensible heat capacityfor an entering air dry-bulb of 27 C, use the formula(Note 3, Cooling Capacity table).Corrected SHC kW = SHC + [1.23 x 10-3 (1 − BF)

x (Cdb − 26.7) x L/s]SHC = 33.4 + [1.23 x 10-3 x (1 − 0.06)

x (27 − 26.7) 2500] kW= 33.4 + 0.867= 34.3 kW

III Heating requirements.To obtain indoor fan motor heat (kW), all accessorypressure drops must be considered, including any re-quirement for accessory electric heat. Enter integratedheating ratings at 2500 L/s and 21 C Edb. At −8 C(air entering outdoor coil) find 23.5 kW integrated heat-ing capacity at 9.8 kW input. The heating load require-ment is 35 kW at −8 C, thus 11.5 kW of supplemen-tary electric heat is needed.The 36 kW heater will easily meet the requirements.

IV Determine indoor fan performance.To obtain the ESP of the fan, the ESP of the ductworkmust be added to the pressure drops of the accesso-ries. Air requirement of system is 2500 L/s at0.20 kPa ESP (duct resistance). The electric heater pres-sure loss is 0.023 kPa and loss in economizer optionis 0.014 kPa; the total fan ESP is the sum of these, or0.237 kPa. From the fan performance table,0.237 Pa ESP at 2500 L/s of air requires 2.11 kW at21.6 r/s (by interpolation).

V Adjust capacities for effects of indoor fan mo-tor heat.Net adjusted capacities are obtained by adding fan heatto integrated heating capacity and subtracting fan heatfrom gross cooling capacities. Total power require-ments are increased by the fan kW.

kW shaft 2.11kW input = = = 2.64 kW

motor efficiency 0.80Adjusted Integrated Heating Capacity

= 23.5 + 2.64= 26.14 kW

Unit power required (heating)= 9.8 + 2.64= 12.44 kW (plus any electric heat)

Net Total Cooling Capacity= 46 − 2.64= 43.36 kW

Net Sensible Heat Capacity= 34.3 − 2.64= 31.66 kW

Total unit power required (cooling)= 15.2 + 2.64= 17.84 kW

9

Selection procedure — English

I Determine job requirements.Estimated cooling requirements:Cooling loadTotal Capacity (TC) . . . . . . . . . . . . . . . 112,000 BtuhSensible Capacity (SHC) . . . . . . . . . . . . 90,000 BtuhOutdoor-Air Temperature (OAT) . . . . . . . . . . . . . 95 FTemperature of Air Entering Indoor CoilDry-bulb (Edb) . . . . . . . . . . . . . . . . . . . . . . . . . . 81 FWet-bulb (Ewb) . . . . . . . . . . . . . . . . . . . . . . . . . . 67 F

Air Quantity (flow rate) . . . . . . . . . . . . . . . . 5000 cfmExternal Static Pressure (ESP)(loss in ducts and diffuser) . . . . . . . . . . . . . 0.8 in. wgEstimated heating requirements:Heating load . . . . . . . . . . . . . . . . . . . . . 115,000 Btuhat Winter Design Temperature . . . . . . . . . . . . 17 F

Temperature of Air Entering Indoor Coil . . . . . . 70 FPower Supply . . . . . . . . . . . . . . . . . . . . . . . . 400-3-50Options: Economizer, Electric Heat.

II Determine unit size.Select unit on cooling capacity required.Enter cooling capacity table at required air quantity(5000 cfm) and indoor coil entering wet-bulb tempera-ture (67 F). Read down table for gross total capacity(TC) and gross sensible capacity (SHC) opposite thecondenser entering air temperature (95 F).Read a TC of 155,000Btuh and SHCof 116,000Btuh.Unit power requirements is 14.8 kW. (These gross ca-pacities must be adjusted for the effects of indoor fanmotor heat and the sensible heat capacity needs to befurther adjusted for dry-bulb temperature other than80 F. See sections IV and V.) To correct gross sensibleheat capacity for an entering dry-bulb of 81 F, use theformula (Note 3, Cooling Capacity table).Corrected SHC Btuh = SHC + [1.10 x (1 − BF)

x (Fdb − 80) x cfm] BtuhSHC = 116,000 + (1.10) x (1 − 0.05)

x (81 − 80) x 5000= 116,000 + 5225= 121,225 Btuh

III Heating requirements.To obtain indoor fan motor heat (kW), all accessorypressure drops must be considered, including any re-quirement for accessory electric heat. Enter integratedheating ratings for the unit at 5000 cfm, 70 F Edb. At17 F (air entering outdoor coil) find 79,000 Btuh in-tegrated heating capacity at 9.8 kW input. The heat-ing load requirement is 115,000 Btuh at 17 F. Thus36,000 Btuh of supplementary electric heat is needed.The 36 kW (123,000 Btuh) heater will easily meet therequirements.

IV Determine indoor fan performance.To obtain the ESP of the fan, the ESP of the ductworkmust be added to the pressure drops of the accesso-ries. Air requirement of system is 5000 cfm at0.8 in. wg ESP (duct resistance). The electric heaterpressure loss is 0.08 in. wg and loss in economizeroption is 0.05 in. wg; the total fan ESP is the sum ofthese, or 0.93 in. wg. From the fan performance table,0.93 in. wg ESP at 5000 cfm of air requires 2.50 Bhpat 1251 rpm (by interpolation).

V Adjust capacities for effects of indoor fan mo-tor heat.Net adjusted capacities are obtained by adding fan heatto integrated heating capacity and subtracting fan heatfrom gross cooling capacities. Total power require-ments are increased by the fan kW.

Bhp x 0.7457 kW/BhpkW input =

motor efficiency2.50 x 0.7457

= = 2.33 kW0.80

Heat equivalent (Btuh)= 2.33 kW x 3412 Btuh per kW= 7950 Btuh

Adjusted Integrated Heating Capacity= 79,000 + 7950= 86,950 Btuh

Unit power required (heating)= 9.8 + 2.33= 12.13 kW (plus any electric heat)

Net Total Cooling Capacity= 155,000 − 7950= 147,050 Btuh

Net Sensible Heat Capacity= 121,225 − 7950= 113,275 Btuh

Total unit power required (cooling)= 14.8 + 2.33= 17.13 kW

10

Performance data

GROSS COOLING CAPACITIES — SI

TEMP (C)AIR ENTOUTDOOR

COIL

INDOOR AIR — L/s / BF2000/0.04 2500/0.06 3000/0.07

Indoor Air — Ewb (C)16 18 20 22 16 18 20 22 16 18 20 22

20TC 45.0 47.0 49.8 52.4 46.6 48.0 49.8 51.4 47.6 49.0 50.8 52.2SHC 39.8 35.2 30.0 26.0 43.8 39.4 33.0 26.8 46.4 42.0 35.4 27.6kW 11.8 12.0 12.2 12.5 11.9 12.0 12.2 12.3 12.0 12.1 12.3 12.4

24TC 43.6 45.8 48.4 51.2 45.4 47.0 49.0 50.8 46.8 48.0 50.0 51.6SHC 39.2 35.0 29.8 25.8 43.2 39.2 33.2 27.0 45.6 41.8 35.8 28.0kW 12.4 12.6 12.9 13.2 12.6 12.7 12.9 13.1 12.7 12.9 13.0 13.2

28TC 42.2 44.4 47.2 50.0 44.2 45.8 48.0 50.2 46.0 47.2 49.0 51.0SHC 38.4 34.6 29.8 25.6 42.6 38.8 33.2 27.2 44.6 41.4 36.0 28.4kW 13.1 13.3 13.6 13.9 13.3 13.5 13.7 13.9 13.5 13.6 13.8 14.0

32TC 41.0 43.2 46.0 48.8 43.0 44.8 47.2 49.6 45.2 46.4 48.2 50.4SHC 37.8 34.2 29.8 25.4 42.0 38.6 33.4 27.4 43.8 41.2 36.2 28.8kW 13.7 14.0 14.3 14.6 14.0 14.2 14.4 14.7 14.2 14.3 14.5 14.8

36TC 39.6 41.8 44.6 47.6 41.8 43.6 46.0 48.8 44.2 45.2 47.0 49.6SHC 37.0 33.8 29.6 25.0 41.2 38.2 33.4 27.4 43.0 40.8 36.4 29.0kW 14.4 14.6 15.0 15.3 14.7 14.9 15.2 15.5 15.0 15.1 15.3 15.6

40TC 38.0 40.0 42.8 45.8 40.4 41.8 44.2 47.2 42.6 43.4 45.2 48.0SHC 35.8 33.0 28.8 24.2 39.8 37.2 32.8 27.0 41.8 40.0 36.0 28.8kW 15.0 15.3 15.7 16.1 15.4 15.5 15.9 16.2 15.7 15.8 16.0 16.3

44TC 36.4 38.2 41.0 44.2 38.8 40.0 42.4 45.4 41.0 41.8 43.4 46.2SHC 34.6 32.2 28.2 23.4 38.4 36.4 32.4 26.4 40.6 39.2 35.8 28.6kW 15.6 15.9 16.3 16.8 16.1 16.2 16.5 17.0 16.4 16.5 16.7 17.1

48TC 34.6 36.4 39.2 42.6 37.4 38.4 40.4 43.8 39.4 40.0 41.4 44.8SHC 33.4 31.4 27.6 22.4 37.0 35.4 32.0 26.0 39.4 38.6 35.4 28.4kW 16.3 16.6 17.0 17.5 16.7 16.9 17.2 17.7 17.1 17.2 17.4 17.9

LEGENDBF — Bypass FactorEwb — Entering Wet-Bulb Temperature (C)kW — Compressor and Outdoor Fan Power InputTC — Total Capacity (kW)SHC — Sensible Heat Capacity (kW)NOTES:1. Ratings are gross, and do not account for the effects of the indoor

fan motor power and heat.2. Direct interpolation is permissible. Do not extrapolate.3. SHC is based on 26.7 C (80 F) db temperature of air entering the

indoor unit. At any other temperature, correct the SHC read from thetable of cooling capacities as follows:Corrected SHCkW = SHC + [1.23 x 10-3 x (1 − BF)

x (Cdb − 26.7) x L/s]Observe the rule of signs. Above 26.7 C (80 F), SHC correction willbe positive; add it to SHC. Below 26.7 C (80 F), SHC correctionwill be negative; subtract it from SHC.

4. Formulas:SHC x 1000kW

Ldb C = Edb C −1.23 x L/s

Leaving wet-bulb = wet-bulb temperature corresponding to enthalpyof air leaving coil (h lwb)

TC x 1000kWhlwb = hewb −

1.20 x L/sWhere hewb is enthalpy of air entering indoor coil (kJ/kg).

11

Performance data (cont)

GROSS COOLING CAPACITIES — ENGLISH

TEMP (F)AIR ENTOUTDOOR

COIL

INDOOR AIR — CFM/BF4400/0.04 5000/0.05 6200/0.07

Indoor Air — Ewb (F)57 62 67 72 57 62 67 72 57 62 67 72

70TC 149 154 166 178 154 157 167 174 161 161 171 178SHC 145 136 108 87 149 145 116 89 159 155 127 91kW 11.9 12.0 12.3 12.7 12.0 12.1 12.3 12.5 12.2 12.2 12.4 12.6

85TC 141 144 158 170 147 148 160 171 155 155 164 174SHC 136 132 108 86 142 142 116 90 151 150 129 94kW 13.3 13.4 13.8 14.2 13.4 13.5 13.9 14.2 13.7 13.7 14.0 14.3

95TC 136 138 152 165 142 142 155 168 151 151 159 171SHC 131 129 108 86 138 138 116 90 145 145 129 96kW 14.2 14.3 14.7 15.2 14.4 14.4 14.8 15.3 14.7 14.7 15.0 15.4

105TC 130 130 143 158 135 135 146 160 144 144 150 164SHC 124 124 105 82 132 132 114 88 140 140 128 94.6kW 15.1 15.2 15.7 16.2 15.4 15.4 15.8 16.3 15.7 15.7 16.0 16.5

115TC 122 122 134 150 128 128 137 152 136 136 141 156SHC 118 118 102 78 126 126 112 85 136 136 126 94kW 16.1 16.1 16.6 17.3 16.3 16.3 16.7 17.4 16.7 16.7 17.0 17.6

LEGENDBF — Bypass FactorEwb — Entering Wet-Bulb Temperature (F)kW — Compressor and Outdoor Fan Power Input (kW)TC — Total Capacity (1000 Btuh)SHC — Sensible Heat Capacity (1000 Btuh)NOTES:1. Ratings are gross, and do not account for the effects of the indoor

fan motor power and heat.2. Direct interpolation is permissible. Do not extrapolate.3. SHC is based on 80 F db temperature of air entering the indoor unit.

At any other temperature, correct the SHC read from the table ofcooling capacities as follows:Corrected SHCBtuh = SHC + [1.10 x (1 − BF)

x (Fdb − 80) x cfm]Observe the rule of signs. Above 80 F, SHC correction will be posi-tive; add it to SHC. Below 80 F, SHC correction will be negative; sub-tract it from SHC.

4. Formulas:SHCBtuh

Ldb (F) = Edb (F) −1.10 x cfm

Leaving wet-bulb = wet-bulb temperature corresponding to enthalpyof air leaving coil (h lwb).

TCBtuhh lwb = hewb −

4.50 x cfmWhere hewb is enthalpy of air entering indoor coil (Btu/lb).

12

FAN PERFORMANCE — SI

AIR VOLUME(L/s)

EXTERNAL STATIC PRESSURE (kPa)0.05 0.08 0.11 0.14 0.17 0.20 0.23 0.26 0.29 0.32 0.35 0.38 0.41 0.44

2000 r/s — — 16.37 17.00 17.82 18.47 19.12 19.73 20.37 21.05 21.72 22.62 22.85 23.45kW — — 0.98 1.05 1.16 1.21 1.27 1.36 1.44 1.56 1.64 1.71 1.78 1.85

2100 r/s — — 16.72 17.47 18.20 18.83 19.47 20.10 20.73 21.42 22.02 22.62 23.02 23.62kW — — 1.15 1.19 1.26 1.33 1.41 1.49 1.59 1.69 1.78 1.93 1.89 1.98

2200 r/s — 16.50 17.23 17.93 18.62 19.23 19.88 20.55 21.23 21.82 22.28 22.75 23.20 —kW — 1.15 1.23 1.31 1.39 1.48 1.56 1.67 1.77 1.88 1.92 1.98 2.05 —

2300 r/s 16.43 17.18 17.78 18.40 19.07 19.70 20.38 21.07 21.70 22.13 22.57 23.00 23.45 —kW 1.21 1.31 1.38 1.46 1.55 1.64 1.74 1.85 1.95 2.02 2.08 2.15 2.22 —

2400 r/s 17.23 17.78 18.28 18.98 19.62 20.27 20.97 21.62 22.04 22.45 22.87 23.27 — —kW 1.41 1.48 1.55 1.65 1.73 1.83 1.94 2.04 2.11 2.16 2.25 2.31 — —

2500 r/s 17.70 18.20 18.78 19.48 20.18 20.82 21.52 21.97 22.35 22.75 23.13 23.63 — —kW 1.56 1.64 1.72 1.82 1.92 1.99 2.09 2.20 2.27 2.33 2.41 2.51 — —

2600 r/s 18.22 18.70 19.47 20.13 20.80 21.43 24.93 22.32 22.68 23.06 23.52 — — —kW 1.75 1.82 1.93 2.02 2.12 2.25 2.30 2.38 2.44 2.51 2.61 — — —

2700 r/s 18.57 19.38 20.13 20.78 21.43 21.90 22.62 22.65 23.00 23.42 — — — —kW 1.91 2.03 2.13 2.24 2.35 2.42 2.49 2.56 2.63 2.73 — — — —

2800 r/s 19.52 20.23 20.85 21.48 21.93 22.30 22.68 23.03 23.40 — — — — —kW 2.16 2.29 2.37 2.45 2.53 2.61 2.69 2.75 2.84 — — — — —

2900 r/s 20.28 20.92 21.52 21.95 22.32 22.67 23.05 23.40 — — — — — —kW 2.42 2.50 2.57 2.66 2.74 2.81 2.88 2.97 — — — — — —

LEGEND

Standard Drive

Field-Supplied Drive

kW — Fan Shaft Powerr/s — Fan SpeedNOTES:1. Fan performance based on wet coils and clean filters and includes

casing losses.

2. Add option and accessory pressure losses to external static pres-sure required before entering table.

3. Minimum airflow for units with electric heat is 1900 L/s.4. Conversion of shaft power to motor input heat value:

kW (shaft)kW (heat) = kW (input) =

motor efficiency5. Motor size: 2.24 kW; average efficiency 80%.6. Motor maximum allowable operating limit is 26.1 kW fan shaft power.

FAN PERFORMANCE — ENGLISH

AIR VOLUME(Cfm)

EXTERNAL STATIC PRESSURE (in. wg)0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7

4400 Rpm — — 972 1025 1059 1093 1128 1160 1192 1226 1260 1295 1326 1358 1370 1403Bhp — — 1.36 1.53 1.62 1.67 1.76 1.87 1.96 2.06 2.17 2.28 2.37 2.45 2.5 2.57

4600 Rpm — 975 1018 1054 1088 1117 1152 1184 1218 1252 1286 1314 1340 1363 1378 1445Bhp — 1.47 1.60 1.68 1.77 1.85 1.93 2.05 2.16 2.27 2.37 2.46 2.55 2.61 2.66 2.82

4800 Rpm 974 1018 1050 1079 1114 1148 1178 1211 1246 1279 1308 1331 1354 1375 1398 1425Bhp 1.56 1.70 1.77 1.84 1.94 2.05 2.14 2.25 2.38 2.49 2.60 2.69 2.75 2.8 2.86 2.95

5000 Rpm 1021 1036 1068 1107 1140 1174 1207 1241 1276 1305 1326 1348 1369 1389 1420 —Bhp 1.80 1.85 1.96 2.06 2.15 2.25 2.36 2.46 2.64 2.73 2.79 2.86 2.94 3.0 3.18 —

5200 Rpm 1045 1075 1105 1139 1173 1206 1240 1274 1304 1325 1345 1366 1387 1415 — —Bhp 1.99 2.10 2.18 2.29 2.39 2.48 2.63 2.75 2.85 2.94 3.0 3.07 3.15 3.28 — —

5400 Rpm 1078 1098 1138 1174 1207 1240 1273 1304 1324 1343 1363 1382 1405 — — —Bhp 2.21 2.29 2.43 2.53 2.64 2.75 2.86 2.96 3.05 3.12 3.17 3.25 3.42 — — —

5600 Rpm 1100 1138 1177 1211 1243 1275 1303 1322 1242 1361 1381 1400 — — — —Bhp 2.36 2.56 2.67 2.80 2.92 3.03 3.11 3.18 3.26 3.85 3.44 3.51 — — — —

5800 Rpm 1142 1181 1216 1248 1280 1307 1325 1344 1363 1381 1400 — — — — —Bhp 2.72 2.84 2.97 3.06 3.17 3.26 3.35 3.42 3.51 3.60 3.66 — — — — —

6000 Rpm 1191 1224 1255 1286 1311 1320 1349 1367 1386 1408 — — — — — —Bhp 3.4 3.14 3.23 3.33 3.41 3.49 3.58 3.65 3.76 3.92 — — — — — —

6200 Rpm 1235 1268 1298 1316 1334 1352 1370 1388 1415 — — — — — — —Bhp 3.03 3.23 3.42 3.59 3.67 3.75 3.81 3.90 4.12 — — — — — — —

LEGEND

Standard Drive

Field-Supplied Drive

Bhp — Brake horsepowerRpm — Revolutions per minuteNOTES:1. Fan performance based on wet coils and clean filters and includes

casing losses.2. Add option and accessory pressure losses to external static pres-

sure required before entering table.

3. Minimum airflow for units with electric heat is 4026 cfm.4. Conversion to motor input heat value:

motor Bhp x 745.7 W/BhpBtuh =

motor efficiency x 0.2931 W/Btuhmotor Bhp x 2544

=motor efficiency

5. Motor size: 3 hp; average efficiency 80%.6. Motor maximum allowable operating limit is 3.5 Bhp.

13

Performance data (cont)

INTEGRATED HEATING CAPACITIES — SI

TEMP (C)AIR ENTOUTDOOR

COIL

AIRFLOW (L/s)2000 2500 3000

Return Air Temp — Edb (C)12 21 27 12 21 27 12 21 27

−28 Cap. 11.9 10.1 8.7 11.9 10.2 8.9 12.1 10.4 9.0kW 7.3 7.6 7.9 7.2 7.6 7.8 7.2 7.6 7.8

−24 Cap. 14.2 12.6 11.2 14.3 12.8 11.4 14.5 12.9 11.5kW 7.7 8.1 8.3 7.6 8.0 8.3 7.6 8.0 8.3

−20 Cap. 16.6 15.0 13.7 16.7 15.2 14.0 16.9 15.4 14.1kW 8.0 8.5 8.8 7.9 8.5 8.8 7.9 8.4 8.7

−16 Cap. 19.3 17.7 16.5 19.3 17.9 16.7 19.5 18.1 16.9kW 8.4 9.0 9.3 8.3 8.9 9.3 8.2 8.8 9.2

−12 Cap. 22.1 20.6 19.5 22.4 20.8 19.7 22.6 21.0 19.9kW 8.8 9.5 9.9 8.7 9.3 9.78 8.6 9.2 9.7

−8 Cap. 24.9 23.3 22.2 25.1 23.5 22.5 25.5 23.7 22.8kW 9.2 9.96 10.4 9.1 9.8 10.3 8.9 9.7 10.2

−4 Cap. 28.1 26.3 25.2 28.5 26.7 25.6 28.6 27.0 26.0kW 9.7 10.5 11.1 9.5 10.3 10.9 9.4 10.2 10.7

0 Cap. 30.7 29.0 27.6 30.9 29.3 28.1 30.9 29.7 28.4kW 10.2 11.1 11.7 10.0 10.9 11.5 9.8 10.7 11.3

4 Cap. 40.4 38.2 36.6 40.0 38.6 37.2 39.0 38.8 37.8kW 10.8 11.8 12.5 10.5 11.6 12.2 10.1 1.3 12.0

8 Cap. 45.0 42.8 41.2 44.0 43.4 41.8 42.2 43.2 42.4kW 11.4 12.5 13.2 10.9 12.2 12.9 10.5 11.9 12.7

12 Cap. 49.4 48.2 47.2 47.6 47.8 47.0 44.8 46.6 46.6kW 12.0 13.4 14.3 11.4 12.8 13.7 10.7 12.3 13.3

16 Cap. 53.8 53.9 53.2 51.2 52.2 52.4 47.2 50.0 50.8kW 12.6 14.2 15.3 11.8 13.4 14.5 11.0 12.8 13.9

LEGENDCap. — Capacity kWEdb — Entering air dry-bulb

temperature (C)Ldb — Leaving air dry-bulb

temperature (C)kW — Compressor and Outdoor-Fan

Power Input

NOTES:1. Integrated heating capacity ratings shown are

not adjusted for the effects of the indoor-fanmotor power and heat. A deduction has beenmade for defrosting the outdoor coils at tem-peratures below 4 C.

2. Direct interpolation is permissible. Do notextrapolate.

3. When using auxiliary and/or supplementaryheating, the maximum allowable leaving-airtemperature is 60 C.Ldb C =

Total heating cap. kW x 1000Edb C +

1.23 x airflow L/s4. For supplementary glycol coil:

Fluid flow L/sfluid capacity kW

=4.187 x fluid temperature drop (C)

INTEGRATED HEATING CAPACITIES — ENGLISH

TEMP (F)AIR ENTOUTDOOR

COIL

AIRFLOW (Cfm)4400 5000 6200

Return Air Temp — Edb (F)55 70 80 55 70 80 55 70 80

−20 Cap. 38 33 28 38 33 29 39 33 29kW 7.2 7.5 7.7 7.2 7.5 7.7 7.2 7.5 7.7

−10 Cap. 49 44 40 49 45 40 50 45 41kW 7.7 8.1 8.2 7.7 8.1 8.4 7.7 8.1 8.3

0 Cap. 61 56 52 61 56 52 62 57 53kW 8.3 8.7 9.1 8.2 8.7 9.0 8.1 8.6 9.0

10 Cap. 74 69 66 75 69.9 66 76 71 67kW 8.8 9.4 9.8 8.7 9.4 9.8 8.6 9.2 9.7

17 Cap. 84 79 75 84 79 76 85 79 77kW 9.2 9.9 10.3 9.1 9.8 10.3 9.0 9.7 10.1

30 Cap. 102 96 92 103 97 93 104 99 95kW 10.1 10.9 11.5 10.0 10.8 11.3 9.8 10.6 11.1

40 Cap. 139 132 127 138 134 129 135 134 130kW 10.9 11.9 12.5 10.7 11.7 12.3 10.3 11.4 12.1

47 Cap. 154 148 142 153 149 144 146 149 146kW 11.5 12.6 13.2 11.2 12.4 13.0 10.7 12.0 12.7

50 Cap. 160 154 151 159 156 152 150 154 152kW 11.8 12.9 13.6 11.4 12.7 13.4 10.8 12.2 13.0

60 Cap. 181 181 179 177 178 178 163 170 172kW 12.5 14.0 15.0 12.1 13.6 14.6 11.2 12.8 13.8

LEGENDCap. — Capacity (1000 Btuh)Edb — Entering air dry-bulb

temperature (F)Ldb — Leaving air dry-bulb

temperature (F)kW — Compressor and Outdoor-Fan

Power Input

NOTES:1. Integrated heating capacity ratings shown are

not adjusted for the effects of the indoor-fanmotor power and heat. A deduction has beenmade for defrosting the outdoor coils at tem-peratures below 40 F.

2. Direct interpolation is permissible. Do notextrapolate.

3. When using auxiliary and/or supplementaryheating, the maximum allowable leaving-airtemperature is 140 F.Ldb F =

Total heating cap. (Btuh)Edb F +

1.10 x airflow cfm4. For supplementary glycol coil:

Fluid flow Gpmfluid capacity (Btuh)

=500 x fluid temperature drop (F)

14

GLYCOL COIL DATA — SI

EGT EDB

L/s2100 2375 2925

% Glycol25 50 25 50 25 50

kW L/s Ldb kW L/s Ldb kW L/s Ldb kW L/s Ldb kW L/s Ldb kW L/s Ldb93

1390.4 2.1 48 85.4 2.1 46 97.1 2.2 47 91.8 2.3 44 109 2.5 43 103 2.5 42

82 74.3 1.7 42 69.1 1.7 40 79.8 1.8 41 74.0 1.8 38 89.8 2.1 38 83.1 2.1 3671 58.3 1.3 36 52.7 1.3 33 62.7 1.4 34 56.5 1.4 32 70.3 1.6 32 63.8 1.6 3093

2179.9 1.8 52 75.0 1.8 50 85.7 1.9 50 80.5 1.9 49 96.5 2.2 48 90.4 2.2 46

82 63.5 1.4 46 58.6 1.4 44 68.5 1.6 45 63.0 1.6 43 77.0 1.7 42 70.3 1.7 4271 47.8 1.0 39 42.5 1.0 37 51.0 1.2 39 45.5 1.1 37 57.5 1.3 37 50.7 1.3 3593

2772.6 1.6 55 68.0 1.7 53 78.1 1.7 54 72.9 1.7 52 87.8 2.0 51 81.6 2.0 49

82 56.5 1.3 49 51.6 1.2 46 60.9 1.4 48 55.4 1.4 45 68.2 1.6 45 61.8 1.5 4471 40.8 0.9 42 35.8 0.9 40 43.7 1.0 42 38.2 0.9 39 49.0 1.1 40 42.6 1.1 38

LEGENDEDB — Entering Dry-Bulb Temperature (C)EGT — Entering Glycol Temperature (C)kW — Heating Capacity (kW)Ldb — Leaving Dry-Bulb Temperature (C)L/s — Liters per Second

NOTES:1. Fluid Dt = 11 C.2. This accessory glycol coil is intended for use with a MINIMUM of 25%

glycol solution. It IS NOT intended for use solely with water due tofreeze-up conditions and the resulting water damage to the condi-tioned space.

GLYCOL COIL DATA — ENGLISH

EGT EDB

Cfm4400 5000 6200

% Glycol25 50 25 50 25 50

Cap. Gpm Ldb Cap. Gpm Ldb Cap. Gpm Ldb Cap. Gpm Ldb Cap. Gpm Ldb Cap. Gpm Ldb200

55310 33 120 293 33 116 333 35 117 315 36 113 375 40 111 353 40 108

180 255 27 108 237 27 105 274 29 106 254 29 102 308 33 101 285 33 98160 200 21 97 181 21 93 215 23 95 194 22 91 241 25 91 217 25 87200

70274 29 127 257 29 124 294 31 124 276 31 121 331 35 119 310 35 116

180 218 23 116 201 23 112 235 25 114 216 25 110 264 28 109 241 28 106160 164 17 104 146 17 100 176 19 103 156 18 99 197 21 99 174 20 96200

80249 26 132 233 27 129 268 28 130 250 28 126 301 32 125 280 32 122

180 194 21 121 177 20 117 209 22 119 190 22 115 234 25 115 212 24 112160 140 15 109 123 14 106 150 16 108 131 15 104 168 18 105 146 17 102

LEGENDCap. — Btuh x 1000EDB — Entering Dry-Bulb Temperature (F)EGT — Entering Glycol Temperature (F)Gpm — Gallons per MinuteLdb — Leaving Dry-Bulb Temperature (F)

NOTES:1. Fluid Dt = 20 F.2. This accessory glycol coil is intended for use with a MINIMUM of 25%

glycol solution. It IS NOT intended for use solely with water due tofreeze-up conditions and the resulting water damage to the condi-tioned space.

ACCESSORY STATIC PRESSURE LOSSES — SI

ACCESSORYAIRFLOW (L/s)

1900 2350 2800Pressure Drop (kPa)

Electric Heater 0.015 0.020 0.030Economizer 0.007 0.012 0.017Glycol Coil 0.045 0.065 0.087

NOTE: Add these pressure losses to the external static pressure beforeentering the Fan Performance table.

ACCESSORY STATIC PRESSURE LOSSES — ENGLISH

ACCESSORYAIRFLOW (Cfm)

4000 5000 6000Pressure Drop (in. wg)

Electric Heater 0.06 0.08 0.12Economizer 0.03 0.05 0.07Glycol Coil 0.18 0.26 0.35

NOTE: Add these pressure losses to the external static pressure beforeentering the Fan Performance table.

15

Electrical data — SI and English

NOMINALV-PH-HZ

VOLTAGERANGE COMPRESSOR OUTDOOR-FAN MOTOR INDOOR-FAN

MOTORELECTRICHEATER*

POWERSUPPLY†

Min Max Qty FLA(each)

RLA(each) Qty FLA

(each)RLA(each)

kW(each) V-Ph-Hz kW Hp FLA kW FLA WSA ICF

400-3-50 342 440 2 16.2 59 2 4.6 9.8 0.75 230-1-50 3.4 4.0 7.0 — — 53 9236 54 107 146

LEGENDFLA — Full Load AmpsHp — Nominal HorsepowerICF — Maximum Instantaneous Current Flow during starting. (Any

point in the starting sequence where the sum of LRA for thestarting compressor plus FLA for all other running compres-sors is maximum.)

kW — Power Output (motors)LRA — Locked Rotor AmpsRLA — Rated Load AmpsWSA — Wire Sizing Amps. One terminal block for each unit. To size

wires, use 125% of the largest motor FLA plus 100% of theFLA for the other motors and heaters in the unit.

*Indoor airflow when electric heat is used must not be less than1900 L/s (4026 cfm).†Four-wire circuit with grounded neutral required to provide 230-1-50source for 230-v motors.

Typical piping and wiring

NEC — National Electrical Code (U.S.A. Standard)

16

Typical wiring schematic

LEGEND

AHA — Adjustable Heat AnticipatorBRK W/AT — Breaks with Amp TurnsC — Contactor, CompressorCAP — CapacitorCB — Circuit BreakerCC — Cooling CompensatorCH — Crankcase HeaterCLO — Compressor LockoutCLS — Cooling Lockout SwitchCOMP — Compressor MotorCR — Control RelayDFR — Defrost RelayDFT — Defrost ThermostatDM — Damper MotorDR — Damper RelayDT — Defrost TimerEC — Enthalpy ControlEQUIP — EquipmentFL — Fuse LinkFPT — Freeze Protection ThermostatFU — FuseGND — Ground

HC — Heater ContactorHPS — High-Pressure SwitchHR — Heater RelayHTR — HeaterIFC — Indoor-Fan ContactorIFM — Indoor-Fan MotorIP — Internal ProtectorL — LightLOR — Lockout RelayLPS — Low-Pressure SwitchLS — Limit SwitchMAT — Mixed Air ThermostatOFC — Outdoor-Fan ContactorOFM — Outdoor-Fan MotorOP — Overcurrent ProtectorPL — Plug AssemblyPRI — PrimaryQT — Quadruple TerminalRVR — Reversing Valve RelayRVS — Reversing Valve SolenoidTB — Terminal BlockTC — Thermostat Cooling

TDR — Time-Delay RelayTH — Thermostat HeatingTRAN — Transformer

Terminal (Marked)

Terminal (Unmarked)

Terminal Block

Splice

Splice (Marked)

Factory WiringField Control WiringField Power WiringAccessory Wiring or Optional WiringAccessoryTo indicate common potential only;not to represent wiring

17

Controls

Base unit operating sequenceCooling — With unit main power on, set thermostat atCOOL position and desired room temperature. Set fan switchat AUTO. position.On a rise in room temperature, cooling contact no. 1 in

thermostat closes, energizing compressor no. 1 contactoron all units. Compressor no. 1 and indoor and outdoor fanmotors start. Compressor no. 1 cycles on demand of ther-mostat to satisfy room conditions.With an additional rise in room temperature, cooling con-

tact no. 2 in thermostat closes, energizing compressor con-tactor no. 2. Compressor no. 2 starts. Compressor no. 2cycles on demand of the thermostat to satisfy room conditions.Heating— Turn unit power on and set thermostat at HEATposition and desired temperature. Set fan at AUTO.position.On a drop in room temperature, heating contact no. 1 in

the thermostat closes, energizing compressor contactorno. 1 and reversing valve and starting compressor no. 1.Indoor blower contactors and outdoor-fan contactors ener-gize at the same time for heat pump cycle.When thermostat second-stage heating contacts close,

compressor contactor no. 2 energizes and compressorno. 2 starts. Units have a built-in electric resistance heatlock-out through the defrost thermostat. Above 4.4 C (40F) (approximate) outdoor temperature, electric resistance heatis locked out and second-stage heat is from compressorno. 2. Below 4.4 C (40 F) (approximate) ambient, whenthermostat first-stage heating contacts close, compressorcontacts no. 1 and no. 2 energize sequentially through atime delay and both compressors are brought on to satisfyheating requirements.On a further drop in room temperature (outdoor ambi-

ent below 4.4 C [40 F]), thermostat second-stage heatingcontacts close, energizing electric resistance heat contactorand second-stage heat operates. Electric heaters with 2 ormore contactors can have outdoor thermostats wired intothe control circuit for additional staging.Automatic changeover —When system selection switchis set at AUTO. position, unit automatically changes fromheating operation to cooling operation when temperatureof the conditioned space rises to cooling lever setting. Whentemperature of conditioned space falls to heating lever set-ting, unit automatically changes from cooling to heating op-eration (with a 1.67 C [3 F] deadband in between).

Continuous air circulation — Turn unit power on. Setsystem control at OFF position, and set fan switch at ONposition. Indoor fan contactor is energized through the ther-mostat switch, and indoor fan runs continuously.NOTE: If controls are set at HEAT, COOL, or AUTO. po-sition, unit operation is as described in Cooling, Heatingand Automatic Changeover sections above, except indoorfan runs continuously.Defrost cycle — The defrost thermostat on the outdoorcoil activates a defrost timer which energizes electric resis-tance heaters and deenergizes reversing valve relays andoutdoor-fan motors. When defrost thermostat is satisfied orwhen 10 minutes have elapsed, reversing valve solenoidsenergize and electric heaters deenergize. The defrost timerprevents defrost again for 90 minutes.The defrost thermostat, in conjunction with a time-delay

relay, prevents electric heat operation above an approxi-mate ambient temperature of 4.4 C (40 F) (depends on coilfrost conditions). If defrost thermostat closes, time-delay re-lay energizes and pulls in compressor contactor no. 2.Both compressors are now operated byW1, andW2 con-

trols electric heat.Economizer operation — Turn unit power on, and setthermostat at COOL or AUTO. position. If outside tem-perature is below setting of outdoor-air changeover ther-mostat, then:Upon a rise in room temperature, cooling contact no. 1

in the thermostat closes. Indoor-fanmotor starts and outdoor-air damper modulates to maintain mixture of outdoor airand return air at present temperature. Cooling is providedusing outdoor air. Mechanical cooling is locked out.At temperature above outdoor air changeover thermo-

stat setting, outdoor-air damper moves to VENT positionwhenever fan is running, and cooling operation is as de-scribed in Cooling section above. When heat is energized,outdoor-air damper moves to vent position. Outdoor-airdamper closes when fan is not operating.

18

Application data

Ductwork — Ductwork must be attached to the curb onall units. Interior installation may proceed before unit is setin place on the roof. If ductwork is to be attached to theunit, do not drill in condensate drain pan area — leaks mayresult.Field power connection—Factory- and field-installed elec-tric heat allows single power entry to the unit for both heat-ing and cooling.Condensate traps— Evaporator coil is draw-through con-figuration. Trap (minimum 100 mm [4 in.] deep) must befield provided prior to start-up on cooling cycle. Install aplug in condensate drain on opposite side of unit from trap.Static pressure limits — When return-air ductwork sys-tems are used, return-side static pressures should be limitedto 0.10 kPa (0.4 in. wg).Operating limits — Airflow and other values in this lit-erature indicate the operating range of the equipment. Op-eration outside these limits is not recommended.Low ambient cooling operation — Units are designedto operate at outdoor temperatures down to 1.7 C (35 F).At temperatures below 1.7 C (35 F), accessory Motor-master Head Pressure Control will permit operation at out-door temperatures as low as −29 C (−20 F).

Roof curb — All curb installations must be counterflashedto prevent water leakage.Power supply — Electric power may be brought to theunit within curb perimeter through fittings provided in thebasepan. Provide power supply in accordance with localcodes.Control wiring — 24-v wiring to thermostat.Remote control panel—When use is required with emer-gency heat (in addition to accessory emergency-heat com-ponents), field-supplied emergency heat switch (DPST toggleswitch) must be used. Emergency heat subbase cannot beused with the remote control panel.Unit selection — Select unit based on cooling only. Donot select heat pumps on heating capacity. Add auxiliaryresistance heat if required.

CONCENTRIC DUCT AIR DISTRIBUTION

NOTE: Do not drill in this area; damage to basepan may result inwater leak.

CONCENTRIC DUCT DETAILS

area indicates block-off panels.NOTES:1. Dimension A, A8 and B, B8 are obtained from field-supplied

ceiling diffuser.2. Dimensions are in millimeters.

19

Application data (cont)

TYPICAL FIELD THERMOSTAT WIRING

LEGENDCOMM — CommunicationsTB — Terminal Block

20

Guide specifications

Packaged Rooftop Air-to-Air Heat Pump —Constant Volume ApplicationSize Range: 52.8 kW (15 tons), Nominal CoolingCarrier Model Number: 50PQPart 1 — General1.01 SYSTEM DESCRIPTIONA. Outdoor, rooftop mounted, electrically controlled, air-

to-air heat pump utilizing reciprocating type compres-sors for heating and cooling duty. Unit shall dischargesupply air vertically as shown on contract drawings.

1.02 QUALITY ASSURANCEA. Unit shall be designed to conform to ASHRAE 15

latest revision (U.S.A.).B. Unit shall be ETL listed (U.S.A.) and CSA certified

(Canada) as a total package for safety requirements.C. Roof curb shall be designed to conform to NRCA

Standards (U.S.A.).D. Insulation and adhesive shall meet NFPA 90A require-

ments for flame spread and smoke generation (U.S.A.).1.03 DELIVERY, STORAGE, AND HANDLINGA. Unit shall be stored and handled per manufacturer’s

recommendations.Part 2 — Products2.01 EQUIPMENTA. General:

Factory-assembled, single-piece, air-to-air heat pump.Contained within the unit enclosure shall be all fac-tory wiring, piping, controls, refrigerant charge(R-22), and special features required prior to fieldstart-up.

B. Unit Cabinet:1. Unit cabinet shall be constructed of galvanized steel,

bonderized, and coated with a prepainted bakedenamel finish.

2. Indoor blower compartment interior cabinet sur-faces shall be insulated with aminimum1⁄2-in. thick,flexible fiberglass insulation, and shall be coatedon the air side. Aluminum foil faced fiberglass in-sulation shall be used in the heating compartment.

3. Cabinet panels shall be easily removable forservicing.

4. Filters will be accessible through a sliding filter rack.5. Holes shall be provided in the base rails for rig-

ging shackles to facilitate overhead rigging.6. Unit shall have a factory-installed, sloped conden-

sate pan.C. Fans:

1. Indoor blower:a. Fan shall be belt drive, as shown on the equip-

ment drawings. Belt drive shall include anadjustable-pitch motor pulley.

b. Fan wheel shall be made from steel, be doubleinlet type with forward curved blades with acorrosion resistant finish and shall be dynami-cally balanced.

c. Bearings shall be sealed and permanentlylubricated.

2. Outdoor fan shall be of the direct drive propellertype with aluminum blades, riveted to corrosion-resistant steel spiders, dynamically balanced, anddischarge air vertically upwards.

D. Compressors:1. Semi-hermetic type with internal and external vi-

bration isolation.2. Equipped with factory-installed crankcase heater

to prevent refrigerant dilution of oil.E. Coils:

1. Indoor and outdoor coils shall have aluminum platefins mechanically bonded to seamless copper tubeswith all joints brazed.

2. Tube sheet openings shall be belled to prevent tubewear.

F. Refrigerant Components:1. Expansion device.2. Filter drier.3. Reversing valve.4. Accumulator.

G. Filter Section:1. Standard filter section shall consist of one size of

factory-installed, low-velocity, 50 mm (2 in.) thickthrowaway fiberglass filters of commercially avail-able sizes.

2. Filter face velocity shall not exceed 1.6 m/s(320 fpm) at nominal airflows.

H. Controls and Safeties:1. Unit Controls:

a. Unit shall be complete with self-contained low-voltage control circuit.

b. Unit shall incorporate an outdoor coil defrostsystem to prevent excessive frost accumula-tion during heating duty, and shall be con-trolled as follows:1) Defrost shall be initiated on the basis of

time and coil temperature.2) A 90-minute timer shall activate defrost

cycle only if coil temperature is low enoughto indicate a heavy frost condition.

3) Defrost cycle shall terminate when de-frost thermostat is satisfied and shall havea positive termination time of 10 minutes.

2. Safeties:Unit shall incorporate a solid-state compressor pro-tector which provides reset capability at the spacethermostat, should any of the following safety de-vices trip and shut off compressor:a. Compressor overtemperature, overcurrent.b. Low-pressure switch.

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Guide specifications (cont)

c. Freezestat, indoor.d. High-pressure switch.

I. Operating Characteristics:1. Unit shall be capable of starting and running at

46 C (115 F) ambient outdoor temperature permaximum load criteria ofARI Standard 340 (U.S.A.).

2. Compressor with standard controls shall be ca-pable of operation down to 1.7 C (35 F) ambientoutdoor temperature in cooling duty.

3. Compressor shall be capable of operation in heat-ing duty down to −29 C (−20 F) ambient outdoor-air temperature.

4. Unit shall be capable of simultaneous heating dutyand defrost cycle operation when using electricheaters indicated in Section L, Special Features.

J. Electrical Requirements:All unit power wiring shall enter unit cabinet at a singlelocation.

K. Motors.1. Compressor motors shall be of the refrigerant-

cooled type with line break thermal and currentoverload protection.

2. All fan motors shall have permanently lubricatedbearings and inherent automatic reset thermal over-load protection.

L. Special Features:Certain standard features are removed and replacedby those features designated by *. Consult your localCarrier Sales office for amending specifications.

* 1. Roof Curbs (Vertical and Horizontal):a. Formed galvanized steel with wood nailer stripand shall be capable of supporting entire unitweight.

2. Horizontal Adapter:Includes factory-assembled adapter and duct tosubstantially improve fan static performance.

* 3. Integrated Economizer:a. Integrated type capable of simultaneous econo-mizer and compressor operation.

b. Includes all hardware and controls to providecooling with outdoor air.

c. Equipped with low-leakage dampers not toexceed 3% leakage at 248 Pa (1.0 in. wg)pressure differential.

d. Capable of introducing up to 100% outdoorair.

e. Equipped with gravity relief damper.f. Capable of going to fully-closed position inthe defrost mode.

* 4. Two-Position Damper:a. Two-position damper package shall includemotor and single-blade damper, and admitsup to 100% outdoor air.

b. Damper shall close upon unit shutoff.

* 5. Electric Resistance Heater:a. Open wire nichrome elements with all nec-essary safety and operating controls.

b. UL and CSA listed (U.S.A.) and indicated onbasic unit informative plate.

c. The heater assembly shall include the follow-ing safety features:1) Automatic reset switches.2) Heat limiters for primary, secondary, over-

current, and thermal protection.3) Branch circuit protection.

d. Unit shall have a single power wiring entrylocation for the heating section.

* 6. Remote Control Panel:Panel shall be a decorative, indoor, wall-mountedpanel consisting of:a. Two-stage heat/2-stage cool thermostat withautomatic changeover.

b. System switch with HEAT-COOL-AUTO.-OFF settings.

c. Fan switch with ON-AUTO. settings.d. Indicator lights for HEAT-COOL-FANoperation.

e. Three unused indicator lights for field use.* 7. Thermostat and Subbase:

Provides staged cooling and heating, automatic(or manual) changeover, fan control, and indica-tor light.

8. Compressor Cycle Delay:Compressor shall be prevented from restartingfor a minimum of 5 minutes after shutdown.

* 9. Head Pressure Control Package:a. Consists of solid-state control and condensercoil temperature sensor for head pressurecontrol.

b. Capable of controlling outdoor-fan motor cy-cling to maintain condensing temperature be-tween 32.2 C and 43.3 C (90 F and 110 F)at outdoor ambient temperatures down to−29 C (−20 F).

* 10. Power Exhaust Package:Package shall include an exhaust fan, motor, anddamper for vertical flow units with economizerto ensure proper building pressurization.

* 11. Barometric Relief Damper Package:a. Package shall include damper, seals, hard-ware, and hoods to relieve excess internalpressure.

b. Damper shall close due to gravity upon unitshutdown.

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* 12. Emergency Heat Package:a. Package shall consist of emergency heat con-trol box containing emergency heat relays andoutdoor thermostat(s), and an emergency heatthermostat subbase with warning light.

b. When mechanical heating is locked out, aux-iliary heat shall be activated when necessary.

13. Glycol Coil:Coil shall be 2-row copper tube (1⁄2-in. OD) withaluminum plate fins (590 fins/m [15 fins/in.]) and(41.28 mm [1.625 in.]) OD copper headers. In-put and output connections shall be (41.28 mm[1.625 in.]) ODM copper stubs for sweat con-nection. Coil shall be furnished with suitable sup-port rails, end plates, and hardware for ready fieldinstallation in heater compartment.

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Carrier Corporation • Syracuse, New York 13221 8-95

Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.

Book 1 4Tab 5a 5a

Page 24 Catalog No. 015-004 Printed in U.S.A. Form 50PQ-C1PDReplaces: 50PQ-C2P