Carrier 40SMC018N User Manual (English)

Questions and Answers:

M
Molly HernandezAug 14, 2025
What to do if my Carrier Air Conditioner compressor and fan of the outdoor unit will not start?
- A
  Andrea McmillanAug 14, 2025
  If the compressor and fan of the outdoor unit won't start, begin by checking the mains power connections and ensuring the unit is switched to the ON position. If that doesn't work, wait for 3 minutes to see if the compressor cycling protection is active. Check and eliminate the cause (refer to “Additional installation instructions”). Also, examine the electrical connections for looseness or errors and repair them if necessary.
C
Carrie MorrisonAug 17, 2025
Why does my Carrier 40SMC018N compressor run continuously?
- B
  brandi49Aug 18, 2025
  If the compressor runs continuously, check the temperature selection. A low refrigerant charge could also be the cause, so verify and add refrigerant if needed. Additionally, air or other non-condensable gases in the circuit might be the issue, requiring you to drain the refrigerant, evacuate, and recharge the system. Finally, check for any obstructions and clean the filter.
R
Ryan LevyAug 21, 2025
What to do if my Carrier Air Conditioner discharge pressure is too high?
- M
  michaelcainAug 21, 2025
  If the discharge pressure is too high, start by cleaning the outdoor coil or removing any obstructions. If the refrigerant charge is too high, drain some refrigerant. Also, if there is air or other non-condensable gases in the circuit, drain the refrigerant, evacuate, and recharge the system. Check the head pressure controller by connecting the fan directly and replace the HPC if necessary.
J
Joseph HicksAug 25, 2025
What to do if my Carrier 40SMC018N Air Conditioner compressor will not start, but outdoor fan is running?
- S
  Stephen SmithAug 25, 2025
  If the compressor won't start but the outdoor fan is running, check the compressor's electrical connections for looseness or errors and repair them. Also, the compressor might be burnt out, seized, or its protection device could be activated, so check for the cause and replace the compressor if necessary.
A
Ashley JacksonAug 28, 2025
What to do if my Carrier Air Conditioner has frequent ice build-up on outdoor coil during heating?
- D
  David Cantu DVMAug 28, 2025
  If there's frequent ice build-up on the outdoor coil during heating, check if the outdoor fan is working correctly and repair if needed. Also, check the electrical connections between the indoor and outdoor units and repair any wrong connections.
J
Joshua OwensSep 1, 2025
What to do if my Carrier 40SMC018N compressor starts, but stops due to its overtemperature protection?
- W
  Wendy HoltSep 1, 2025
  If the compressor starts but stops due to overtemperature protection, it could be due to a wrong refrigerant charge (excessive or low) or air/non-condensable gases in the circuit; in this case, drain refrigerant, evacuate, and recharge. Remove any obstructions. Check cause and repair. Check and replace. Check and remove obstructions.
H
Heather NelsonSep 5, 2025
What to do if my Carrier 40SMC018N Air Conditioner discharge pressure is too low?
- M
  Michael CooleySep 5, 2025
  If the discharge pressure is too low, it could be due to a low refrigerant charge, in which case you should add refrigerant. Another cause could be a dirty or obstructed outdoor coil, so clean or remove any obstructions. Also, a dirty indoor unit air filter can cause this issue, so clean the filter.
L
Lisa PerezSep 9, 2025
What causes outdoor fan cycling due to its overtemperature protection in Carrier 40SMC018N?
- J
  Jason JohnsonSep 9, 2025
  If the outdoor fan is cycling due to its overtemperature protection, the fan capacitor might be faulty, so replace it. Check connections and repair.

Carrier 40SMC018N Specifications

General

Model	40SMC018N
Refrigerant	R-410A
Voltage	208/230V
Operating Temperature Range (Cooling)	62°F - 90°F
Type	Mini-Split
Cooling Capacity	18000 BTU
Cooling Capacity (BTU/hr)	18000
Weight (Outdoor Unit)	88 lbs
Power Supply	208/230V, 1 Phase, 60 Hz
Indoor Unit Noise Level	42 dB
Outdoor Unit Noise Level	55 dB(A)
Outdoor Unit Weight	88 lbs
Voltage (V)	208/230

Summary

Attention Installers and Service Technicians

R-410A Refrigerant Handling and System Notes

Key precautions for R-410A systems, including pressure, liquid charging, oil compatibility, and venting.

Dimensions and Weight

Unit Dimensions and Specifications

Detailed dimensions (A-F) and weight (kg) for various outdoor unit models.

Pipe Connections

Details on pipe length, height difference, and pipe diameters for gas and liquid lines.

Minimum Clearances

Installation Clearance Requirements

Specifies minimum clearances (A-F) around the outdoor unit for proper operation and servicing.

Operating Limits

Cooling and Heating Operating Conditions

Outlines maximum and minimum operating temperature and voltage limits for cooling and heating.

General Information

Unit Installation Guidelines

Covers essential steps like checking mains supply, pipe connections, and system testing for installers.

Choosing the Installation Site

Provides recommendations and positions to avoid for optimal outdoor unit placement.

Installation Warnings and Best Practices

Installation Practices to Avoid

Illustrates common installation mistakes to avoid, such as incorrect connections, clearances, and pipe handling.

Refrigerant Connections

Preparing and Making Refrigerant Connections

Covers essential steps like ensuring cleanliness, proper vacuuming, and using correct tools for R-410A.

Flaring and Connecting Tubing

Details on flaring copper tubes, connecting them to the unit, and the importance of proper tightening torque.

Air Purging and Leak Checks

Describes the process of air purging using a vacuum pump and performing leak checks on refrigerant lines.

Electrical Connections and Data

Electrical Connections (018-024 Size)

Provides detailed wiring diagrams and a legend for terminal box connections for specific unit sizes.

Electrical Connections (028-048 Size)

Provides detailed wiring diagrams and a legend for terminal box connections for larger unit sizes.

General Electrical Connection Procedures

Covers mains supply connection, wire connection, and ground connection importance.

Electrical Data and Specifications

Details electrical data including power input, starting current, and main power connection wire sizes.

Pump Down and Refrigerant Charge Check

Pump-Down Procedure

Explains the operation to collect refrigerant in the outdoor unit before disconnecting lines.

Checking Refrigerant Charge

Details how to check and correctly charge refrigerant into the system.

Unit Maintenance and Troubleshooting

Unit Maintenance Procedures

Describes coil cleaning and other maintenance tasks for qualified personnel.

Troubleshooting Common Issues

Lists common problems with the compressor, fan, and system operation, with suggested causes and solutions.

Installation Supplement for Heat Pump Units

Operating Range for Heat Pumps

Refers to Table III for operating limits relevant to heat pump functionality.

Key Features: HPC, HIP, LRPS

Details the Head Pressure Controller (HPC), High Pressure Cut-out (HIP), and Loss of Refrigerant Pressure Switch (LRPS).

Condensing Temperature Controller

Explains the wiring diagram, operation modes (full voltage, low voltage, proportional band), and temperature settings.

Related product manuals

Carrier 40SMC N Series

Carrier 40SMC018N User Manual

Table of Contents

Questions and Answers:

Carrier 40SMC018N Specifications

Summary

Attention Installers and Service Technicians

R-410A Refrigerant Handling and System Notes

Dimensions and Weight

Unit Dimensions and Specifications

Pipe Connections

Minimum Clearances

Installation Clearance Requirements

Operating Limits

Cooling and Heating Operating Conditions

General Information

Unit Installation Guidelines

Choosing the Installation Site

Installation Warnings and Best Practices

Installation Practices to Avoid

Refrigerant Connections

Preparing and Making Refrigerant Connections

Flaring and Connecting Tubing

Air Purging and Leak Checks

Electrical Connections and Data

Electrical Connections (018-024 Size)

Electrical Connections (028-048 Size)

General Electrical Connection Procedures

Electrical Data and Specifications

Pump Down and Refrigerant Charge Check

Pump-Down Procedure

Checking Refrigerant Charge

Unit Maintenance and Troubleshooting

Unit Maintenance Procedures

Troubleshooting Common Issues

Installation Supplement for Heat Pump Units

Operating Range for Heat Pumps

Key Features: HPC, HIP, LRPS

Condensing Temperature Controller

Related product manuals