Carrier NP034-074 specifications Detailed Check

Page 53

Table 14 Ð Economizer Control Board Checkout,

Test 2

MOTOR

PROCEDURE

 

EXPECTED RESULT

TEST

 

 

AND RESPONSE

A

Turn enthalpy set point

1.

The relays energize. If not,

 

potentiometer to the

 

check return enthalpy re-

 

A position.

 

sistor. If resistor is o.k.,

 

 

 

control board is faulty.

 

 

2.

Motor drives open. If re-

 

 

 

lays energize, but motor

 

 

 

does not drive open, the

 

 

 

control board is faulty.

B

Turn enthalpy set point

1.

The relays deenergize. If

 

potentiometer to the

 

not, control board is faulty.

 

D position.

2.

Motor drives closed. If re-

 

 

 

lays deenergize by motor

 

 

 

does not drive closed, the

 

 

 

control board is faulty.

 

 

 

 

Test 3:

1.Apply 24 VAC power to terminals T0 and T2 of the con- trol board.

2.Apply 24 v between terminals 1 and T2, and jumper ter- minal T0 to terminal 1.

3.Remove the mixed-air sensor connected between termi- nals S1 and S2, and replace it with a 5490-ohm resistor.

4.Remove outdoor-air enthalpy sensor between terminals 11 and SO, and replace it with a 1.2 kOhm resistor.

5.Turn the minimum position potentiometer fully counter- clockwise.

6.Turn enthalpy set point potentiometer to the A setting.

7.Refer to Table 15.

Table 15 Ð Economizer Control Board Checkout,

Test 3

MOTOR

PROCEDURE

EXPECTED RESULT

TEST

 

AND RESPONSE

A

Turn mixed-air potenti-

Motor should drive to mid-

 

ometer to the midpoint

stroke with the set point set

 

position.

between 60 and 70 F. If not,

 

 

the control board is faulty.

B

Turn mixed-air

Motor drives open, If not, the

 

potentiometer fully

control board is faulty.

 

counterclockwise.

 

C

Turn mixed-air potenti-

Motor drives closed. If not,

 

ometer fully clockwise.

the control board is faulty.

 

 

 

Test 4

Refer to Table 16 for the correct procedure for test 4.

Unit Control Board Checkout Ð The following tools are required to perform the troubleshooting tasks detailed in this section:

·1.5-v battery

·2 sets of jumper wires with alligator clips

·Multimeter

·Toggle switch with 14-in. wires terminated with 1¤4-in. spade connectors

Read these instructions completely before attempting to troubleshoot the control board. Failure to follow the steps precisely could result in damage to unit, personal in- jury, or death.

The control board checkout procedure consists of 2 parts: A basic check to verify availability of 24 and 115 v to the control board and a detailed check of each circuit within the board.

Table 16 Ð Economizer Control Board Checkout,

Test 4

MOTOR

 

PROCEDURE

EXPECTED RESULT

TEST

 

 

AND RESPONSE

A (Outdoor-

1.

Connect the enthalpy

Milliammeter reading

Air Sensor)

 

sensor terminal 1 to

should be between

 

 

terminal 1 on the motor.

3 and 24 mA if the

 

2.

Connect the positive ter-

sensor is operating

 

 

minal of a DC milliam-

correctly. If the read-

 

 

meter to terminal S of

ing is 0 mA, the

 

 

the sensor.

sensor is either

 

3.

Connect the negative

wired backward or is

 

 

terminal of a DC milliam-

defective.

 

 

meter to terminal SO of

 

 

 

the enthalpy board.

 

B (Indoor-

1.

Connect the enthalpy

Milliammeter reading

Air Sensor)

 

sensor terminal 1 to

should be between

 

 

terminal 1 on the motor.

3 and 24 mA if the

 

2.

Connect the positive ter-

sensor is operating

 

 

minal of a DC milliam-

correctly. If the read-

 

 

meter to terminal S of

ing is 0 mA, the

 

 

the sensor.

sensor is either

 

3.

Connect the negative

wired backward or is

 

 

terminal of a DC milliam-

defective.

 

 

meter to terminal SR of

 

 

 

the enthalpy board.

 

BASIC CHECK Ð Refer to Fig. 64 for control board com- ponent identi®cation.

NOTE: All plugs (except P1) are labeled for easy identi®- cation. Plug P1 can be identi®ed by its orange color.

1.Turn unit power off. Disconnect plug P1 from control board.

2.Turn unit power on and check voltage across Pin R and Pin C at plug P1. If voltage reads 18 to 30 v, skip to Step 5.

3.Turn unit power off. Disconnect plug P3.

4.Turn unit power on and measure voltage across wires on plug P3, Pins 1 and 2 (wires coming from the unit). If voltage reads 18 to 30 v, there is either a bad connection between plug P3 and control board, or the control board is defective. Verify the connection at this point and pro- ceed to Step 5. If there is no voltage, check the circuit breaker and transformer in the 24-v control circuit of the unit.

5.Turn unit power off and disconnect plug P4 from the con- trol board.

6.Switch scale on meter to read 115 v.

7.Turn unit power on and check voltage across Pin 6 on plug 4 and unit ground (wires coming from the unit). If voltage reads 104 to 122 v, there is adequate power avail- able to the board. Verify connection at this point and pro- ceed to Step 8. If there is no voltage, check the circuit breaker and transformer in the 115-v control circuit of the unit.

8.After verifying that 24-v and 115-v supply power is avail- able to the control board, turn unit power off and recon- nect plugs P1, P3, and P4. Proceed to Detailed Check section below.

DETAILED CHECK

NOTE: Plug P1 must be disconnected in order to perform any of the troubleshooting steps detailed in this section. To save time, reconnect plug P1 only after you have completed all of the required troubleshooting.

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Contents Installation, Start-Up Service Instructions General ContentsRigging Label Ð Physical Data 034, 044 Units Ð Physical Data 054-074 Units Weight Distribution and Center of Gravity Operating Weights of Options and AccessoriesFt-in Ð Roof Curb 034, 044 UnitsDeg Ð Roof Curb 054-074 Units054,064 270 105¤8 074 255 101¤16 Ð Condenser Section Roof Curb 054-074 Units OnlyOutdoor-Air Inlet Adjustments Install Outdoor HoodsEconomizer Settings Unit Sizes 034Unit Size Weight Ð Base Unit Dimensional Drawing 50DJ,DK,NP034,044 Units 8700 3946 5969 19-7 6717 Weight Ft-in Ð Base Unit Dimensional Drawing 50DJ,DK,NP054-074 UnitsDrain Location Selection AT 50% RH Approx DegField Electrical Connections Field Wire RoutingField Power Wiring Connections Electrical Data, 034 Units 11.0 81.2 100 90.8 110 10.0 15.2 96.4 125 15.0 22.0 103.293.8 110 10.0 15.2 99.4 125 15.0 22.0 106.2 10.0 14.0 84.2 11065.8 73.6 10.0 12.2 78.0 100 15.0 18.0 83.875.6 10.0 12.2 80.0 100 15.0 18.0 85.8 67.8Electrical Data, 044 Units 11.0 96.9 125 106.5 125 10.0 15.2 112.1 15.0 22.0 118.9 150109.5 125 10.0 15.2 115.1 15.0 22.0 121.9 150 10.0 14.0 99.9 12576.3 100 84.1 110 10.0 12.2 88.5 15.0 18.0 94.386.1 110 10.0 12.2 90.5 15.0 18.0 96.3 10.0 11.0 78.3 100Electrical Data, 054 Units 15.0 21.0 129.6 175 10.0 15.2 144.8 175 15.0 22.0 151.6 200 20.0 28.0 157.610.0 15.2 150.8 200 15.0 22.0 157.6 20.0 28.0 163.6 20.0 27.0 135.6 17515.0 17.0 104.3 125 10.0 12.2 116.5 150 15.0 18.0 122.3 20.0 22.0 126.310.0 12.2 121.5 150 15.0 18.0 127.3 20.0 22.0 131.3 20.0 22.0 109.3 125Electrical Data, 064 Units 15.0 21.0 145.6 175 10.0 15.2 160.8 200 15.0 22.0 167.6 20.0 28.0 173.610.0 15.2 166.8 200 15.0 22.0 173.6 20.0 28.0 179.6 225 20.0 27.0 151.6 20015.0 17.0 114.6 150 10.0 12.2 126.8 150 15.0 18.0 132.6 20.0 22.0 136.6 17510.0 12.2 131.8 150 15.0 18.0 137.6 175 20.0 22.0 141.6 20.0 22.0 119.6 150Electrical Data, 074 Units 15.0 21.0 166.8 225 10.0 15.2 182.0 225 15.0 22.0 188.8 250 20.0 28.0 194.810.0 15.2 188.0 250 15.0 22.0 194.8 20.0 28.0 200.8 20.0 27.0 172.8 22515.0 17.0 133.8 175 10.0 12.2 146.0 175 15.0 18.0 151.8 200 20.0 22.0 155.810.0 12.2 151.0 200 15.0 18.0 156.8 20.0 22.0 160.8 20.0 22.0 138.8 175Field Control Thermostat Wiring Field Wiring for Building Pressurization and Smoke Purge Gas Piping Details Installing Flue/Inlet Hoods 48 Series Units OnlyFlue Hood PRE-START-UP Ð Field-Supplied Evaporator-Fan Pulley Data, 034,044 Units Gas Manifold Pressure 48 Series Units OnlyAir Quantity Limits cfm Ð Field-Supplied Evaporator-Fan Pulley Data, 054-074 UnitsHEATING, Units Without Economizer Initial CheckGeneral Compressors ServiceEVAPORATOR-FAN MOTORS, PULLEYS, and Belts Liquid Service VALVES, Filter DRIERS, and Sight GlassesPower Exhaust MOTORS, PULLEYS, and Belts Burner Section Detail 48 Series Units Only Lubrication Modulating Power Exhaust Damper MotorCondenser FAN Adjustment AdjustmentsBelt Installation and Tensioning Pulley Alignment Charging Chart, 044 Units System One Condenser Fan Running Charging Chart, 064 Units System All Condenser Fans Running Main Burner Removal 48 Series Units Only Auxiliary Switch Stroke AdjustmentCompressor Protection Protective DevicesGas Heat 48 Series Units Only Electric Heat 50 Series Units OnlyEconomizer Motor Checkout Economizer Control Board Checkout TestDetailed Check Control Board Component Arrangement Page Compressor Lockout Connections ACC Gas Heat Sections 48DJ,NP034,044 Units Gas Heat Sections 48DJ,NP054-074 Units Gas Heat DK034,044 Units Gas Heat DK054-074 Units Typical Wiring Schematic 48/50DJ,50DW Units 054-074 Shown Typical Wiring Schematic 48/50DJ,50DW Units 054-074 Shown Typical Wiring Schematic 48/50DK,50DY Units 054-074 Shown Typical Wiring Schematic 48/50DK,50DY Units 054-074 Shown Page Page Page Page Packaged Service Training Page RETURN-AIR Temperature OUTDOOR-AIR TemperatureModel no Serial no Date Technician Supply Voltage L1-L2

NP034-074 specifications

The Carrier NP034-074 is an advanced rooftop unit designed for commercial heating, ventilation, and air conditioning (HVAC) applications. This unit is part of Carrier’s extensive range of rooftop units that are known for their energy efficiency, reliability, and innovative features. The NP034-074 series is particularly recognized for its robust performance in diverse environmental conditions, making it ideal for a variety of commercial building types.

One of the standout features of the NP034-074 is its high-efficiency compressor. Equipped with a scroll compressor, the unit offers enhanced performance and quieter operation compared to traditional reciprocating compressors. This design not only improves energy efficiency but also reduces operating costs over time. The unit is designed to meet or exceed the latest efficiency standards, ensuring that businesses can enjoy optimal indoor comfort while keeping energy consumption low.

The NP034-074 also integrates advanced control technologies that provide users with greater flexibility and ease of operation. The intuitive control system allows for precise temperature management and can be easily integrated with building automation systems. This enables users to monitor and adjust settings remotely, ensuring consistent and efficient climate control throughout the facility.

Another key characteristic of the NP034-074 is its robust construction. Built to withstand various weather conditions, the unit features a galvanized steel cabinet with a powder-coated finish for corrosion resistance. Its design also facilitates easy access for maintenance and service, which minimizes downtime and operational interruptions.

In terms of air distribution, the NP034-074 incorporates a powerful blower system that ensures even and effective airflow throughout the space. This design improves indoor air quality by enhancing ventilation while maintaining comfort levels. Additionally, the unit can be customized with options such as economizers and variable speed fans to optimize performance based on specific building needs.

The NP034-074 is a versatile and reliable choice for businesses looking to enhance their HVAC systems. With its combination of energy efficiency, advanced technology, and robust construction, this rooftop unit stands out as a top choice for commercial climate control solutions.
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