Carrier PF4MNA - User Manual

To Next Page

Installation Instructions

NOTE: Read the entire instruction manual before starting the installation.

SAFETY CONSIDERATIONS

Improper installation, adjustment, alteration, service, maintenance, or

use can cause explosion, fire, electrical shock, or other conditions which

may cause death, personal injury or property damage. Consult a

qualified installer, service agency, or your distributor or branch for

information or assistance. The qualified installer or agency must use

factory-authorized kits or accessories when modifying this product.

Refer to the individual instructions packaged with kits or accessories

when installing.

Follow all safety codes. Wear safety glasses, protective clothing and

work gloves. Have a fire extinguisher available. Read these instructions

thoroughly and follow all warnings or cautions included in literature and

attached to the unit. Consult local building codes and the current editions

of the National Electrical Code (NEC) NFPA 70.

In Canada, refer to the current editions of the Canadian Electrical Code

CSA C22.1.

Recognize safety information. This is the safety-alert symbol . When

you see this symbol on the unit and in instruction manuals, be alert to the

potential for personal injury.

Understand the signal words DANGER, WARNING, and CAUTION.

These words are used with the safety-alert symbol. DANGER identifies

the most serious hazards which will result in severe personal injury or

death. WARNING signifies hazards which could result in personal

injury or death. CAUTION is used to identify unsafe practices which

may result in minor personal injury or product and property damage.

NOTE is used to highlight suggestions which will result in enhanced

installation, reliability, or operation.

INTRODUCTION

Model PF4MNA Fan Coils are designed for flexibility and can be used

for upflow, horizontal, or downflow (kit required) and manufactured and

mobile home applications. These units are designed to meet the low air

leak requirements currently in effect. Because of this, the units need

special attention in the condensate pan and drain connection area and

when brazing tubing. These units are designed specifically for R-410A

refrigerant and must be used only with R-410A refrigerant air

conditioners and heat pumps as shipped. These units are available for

systems of 18,000 through 60,000 Btuh nominal cooling capacity.

Factory-authorized, field-installed electric heater packages are available

in sizes 5 through 30kW. See Product Data literature for available

accessory kits.

HEATER PACKAGES

Factory-approved, field-installed, UL listed heater packages are

available from your equipment supplier. See unit rating plate for a list of

factory-approved heaters. Heaters that are not factory approved could

cause damage which would not be covered under the equipment

warranty.

INSTALLATION

CHECK EQUIPMENT

Unpack unit and move to final location. Remove carton taking care not

to damage unit.

Inspect equipment for damage prior to installation. File claim with

shipping company if shipment is damaged or incomplete. Locate unit

rating plate which contains proper installation information. Check rating

plate to be sure unit matches job specifications.

MOUNT UNIT

Unit can stand or lie on floor, or hang from ceiling or wall. Allow space

for wiring, piping, and servicing unit.

IMPORTANT: When unit is installed over a finished ceiling and/or

living area, building codes may require a field-supplied secondary

condensate pan to be installed under the entire unit. Some localities may

allow as an alternative, the running of a separate, secondary condensate

line. Consult local codes for additional restrictions or precautions.

NOTE: Nuisance sweating may occur if the unit is installed in a high

humidity environment with low airflow.

UPFLOW INSTALLATION

If return air is to be ducted through a floor, set unit on floor over opening

and use 1/8 to 1/4-in (3 to 6 mm) thick fireproof resilient gasket between

duct, unit, and floor.

Side return is a field option on slope coil models. Cut opening per

dimensions. (Fig. 1) A field-supplied bottom closure is required.

DOWNFLOW INSTALLATION

In this application, field conversion of the evaporator is required using

accessory downflow kit along with an accessory base kit. Use fireproof

resilient gasket, 1/8 to 1/4-in (3 to 6 mm) thick, between duct, unit, and

floor.

PF4MNA

DIRECT EXPANSION FAN COIL

SIZES 018 TO 061

WARNING

ELECTRICAL OPERATION HAZARD

Failure to maintain proper clearances could result in personal injury or

death.

Before installing or servicing unit, always turn off all power to unit.

There may be more than 1 disconnect switch. Turn off accessory heater

power if applicable.

CAUTION

PRODUCT OR PROPERTY DAMAGE HAZARD

Failure to follow this warning caution may result in product or property

damage.

The conversion of the fan coil to downflow requires special procedures

for the condensate drains on both A-coil and Slope-coil units. The

vertical drains have an overflow hole between the primary and

secondary drain holes. This hole is plugged for all applications except

downflow, and must be used for downflow. During conversion process,

remove plastic cap covering vertical drains only and discard. Remove

plug from overflow hole and discard. At completion of downflow

installation, caulk around vertical pan fitting to door joint to retain low

air leak performance of the unit.

Main Page

Need help?

Do you have a question about the Carrier PF4MNA and is the answer not in the manual?

The PF4MNA Direct Expansion Fan Coil is a versatile indoor air handling unit designed for residential and manufactured home applications. It is compatible with R-410A refrigerant air conditioners and heat pumps, and is available for systems with nominal cooling capacities ranging from 18,000 to 60,000 Btuh. The unit is designed to meet low air leak requirements, which necessitates special attention during installation, particularly around the condensate pan and drain connections, and when brazing tubing.

Function Description:

The primary function of the PF4MNA fan coil is to circulate air, condition it (cooling or heating), and distribute it throughout a space. When connected to an outdoor air conditioner, it provides cooling. When connected to a heat pump, it provides both heating and cooling. Factory-authorized, field-installed electric heater packages, available in sizes from 5 to 30kW, can be added to provide supplemental or emergency electric heat. The unit can be configured for upflow, horizontal left, horizontal right (with conversion kit), or downflow (with conversion kit) applications, offering significant installation flexibility.

Important Technical Specifications:

Refrigerant Compatibility: Specifically designed for R-410A refrigerant.
Cooling Capacity: Available for systems from 18,000 to 60,000 Btuh.
Electric Heater Packages: Available in 5 to 30kW sizes.
Low Air Leak Design: Meets current low air leak requirements.
Drain Connections: Equipped with primary and secondary 3/4-inch FPT drain connections.
Electrical: Transformer is factory wired for 230V operation, with provisions for 208V applications. Low voltage circuit protection is provided by a 5-amp fuse (for sizes 018, 024, 030, 036, 042, 048, 060) or an inline 5-amp automotive type fuse (for sizes 019, 025, 031, 037, 043, 049, 061).
Airflow Performance: Detailed airflow tables (CFM) are provided for various external static pressures (in. wc) and blower speeds (High, Medium, Low), with corrections for dry-to-wet coil conditions and electric heater static pressure drop. Airflow is based on dry coil at 230V with factory-approved filter and electric heater. Airflow at 208V is approximately 10% lower for certain models (018, 024, 030, 036, 042, 048, 060), while X13 motor models (019, 025, 031, 037, 043, 049, 061) maintain similar airflow at 208V due to constant torque.
Clearances: Minimum 24-inch (610 mm) clearance from access panels is recommended for manufactured housing applications. For 20-30kW electric heaters, a 1-inch (25 mm) clearance to combustible materials is required for the first 36-inches (914 mm) of supply duct.

Usage Features:

Installation Flexibility: Can be installed in upflow, horizontal (left or right), or downflow configurations. Downflow and horizontal right applications require specific accessory kits and conversion procedures.
Modular Design (Sizes 060 and 061): These larger units can be disassembled for easier transport and reassembly in confined installation spaces.
Condensate Management: Requires proper installation of primary and secondary condensate traps to ensure optimal drainage and prevent property damage. Full-size P-traps are essential, and shallow running traps are inadequate. An external secondary condensate pan or a separate secondary condensate line may be required by local codes if the unit is installed over a finished ceiling or living area.
Air Duct Connections: Supply-air duct connects over 3/4-inch (19 mm) flanges. Flexible connectors are recommended to prevent vibration transmission. Heat-resistant material is required for flexible connectors at the discharge when an electric heater is installed. Ductwork in unconditioned spaces must be insulated and vapor-barriered.
Motor Speed Selection: For models 018, 024, 030, 036, 042, 048, 060, fan speed is selected at the printed-circuit board (SPT terminal). For models 019, 025, 031, 037, 043, 049, 061, fan speed is selected directly at the motor (taps 1, 2, or 3). Low speed (red) is for mismatched outdoor units, medium speed (blue) for straight matched operations, and high speed (black) for high external static duct systems.
Time Delay Relay (TDR): Models 018, 024, 030, 036, 042, 048, 060 feature a TDR jumper on the PCB, which can be severed to disable the TDR function. Some speed taps on X13 motors (019, 025, 031, 037, 043, 049, 061) are pre-programmed with a time delay circuit.
Heater Staging: Controls are factory-circuited for single-stage operation. Two-stage and three-stage operation require outdoor thermostat kits (KHAOT0301FST and KHAOT0201SEC).
Low Voltage Wiring: Uses 18 AWG color-coded, insulated wire for connections up to 100 feet (30 m); 16 AWG for longer runs. All wiring must be NEC Class 1 and separated from incoming power leads.
Manufactured Housing Applications: Unit must be secured to the structure using field-supplied hardware. Supplemental electric heat must be locked out at outdoor temperatures above 40°F (4°C), except for heat pump defrost cycles, as per Code of Federal Regulations, Title 24, Chapter XX, Part 3280.714.
Accessory Connections: Provisions for connecting electronic air cleaners (requires field-supplied transformer) and humidifiers/humidistats.

Maintenance Features:

Filter Access: Units should never be operated without a filter. Factory-authorized filter kits can be used for internal filter placement. For applications where internal access is impractical, a field-supplied filter must be installed in the return air duct system.
Periodic Maintenance: To ensure high performance and minimize equipment failure, periodic maintenance by a qualified dealer is essential. The only consumer-recommended maintenance is monthly filter replacement or cleaning.
Condensate Trap Priming: All condensate traps must be primed and tested for leaks after installation.
Insulation: Condensate traps located above a living area should be insulated.
Brazing Precautions: A brazing shield must be used when connecting refrigerant tubing to prevent damage to the unit surface and condensate pan fitting caps. Wet cloths should be wrapped around fittings to protect TXV and factory-made joints during brazing.