Carrier FB4CNP - User Manual

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FB4CNF

FB4CNP

FX4D

Installation Instructions

FAN COIL UNITS

FOR R−410A REFRIGERANT

SIZES 018 TO 061

NOTE: Read the entire instruction manual before starting the

installation.

TABLE OF CONTENTS

PAGE

SAFETY CONSIDERATIONS 1........................

INTRODUCTION 1..................................

HEATER PACKAGES 2..............................

INSTALLATION 2...................................

Step 1 — Check Equipment 2.........................

Step 2 — Mount Unit 2..............................

Step 3 — Air Ducts 4...............................

Step 4 — Electrical Connections 4.....................

Step 5 — Refrigerant Tubing Connection and Evacuation 7..

Step 6 — Refrigerant Flow−Control Device 7.............

Step 7 — Condensate Drains 7........................

Step 8 — Accessories 8..............................

Step 9 — Sequence of Operation 8.....................

START−UP PROCEDURES 9..........................

CARE AND MAINTENANCE 9........................

AIRFLOW PERFORMANCE TABLES 9.................

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.

ELECTRICAL OPERATION HAZARD

Failure to follow this warning could result in personal injury

or death.

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

unit. There may be more than one disconnect switch. Turn off

accessory heater power if applicable. Lock out and tag switch

with a suitable warning label.

WARNING

CUT HAZARD

Failure to follow this caution may result in personal injury.

Sheet metal parts may have sharp edges or burrs. Use care and

wear appropriate protective clothing and gloves when

handling parts.

CAUTION

INTRODUCTION

FB4C and FX4D models are R−410A Fan Coils designed for

installation flexibility. These units leave the factory compliant with

low leak requirements of less than 2% cabinet leakage rate at 0.5

inches W.C. and 1.4% cabinet leakage rate at 0.5 inches W.C. when

tested in accordance with ASHRAE 193 standard.

FB4CNF(018−048) uses a refrigerant piston metering device. A

TXV is used on FB4CNP and FX4D(018−061). All these fan coils

use a multi−tap ECM motor for efficiency. The units have be

designed for upflow, downflow (kit required), and horizontal

orientations, including manufactured and mobile home

applications.

These units require a field supplied air filter, and are designed

specifically for 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 all available

accessory kits.

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Summary

Installation

Step 1 Check Equipment

Verify unit contents and check for damage upon arrival.

Step 2 Mount Unit

Instructions for mounting the fan coil unit in various orientations.

Step 3 Air Ducts

Connect supply-air and return-air ducts to the unit, ensuring proper sealing.

Step 4 Electrical Connections

Detail low-voltage and line-voltage wiring procedures, adhering to codes.

Step 5 Refrigerant Tubing Connection and Evacuation

Connect refrigerant lines and evacuate the system to 500 microns.

Step 6 Refrigerant Flow-Control Device

Discusses piston and TXV devices, including replacement and installation.

Step 7 Condensate Drains

Proper installation of condensate drains and traps to prevent water damage.

Step 8 Accessories

Instructions for installing optional accessories like humidifiers.

Step 9 Sequence of Operation

Explains the unit's operation modes: continuous fan, cooling, and heating.

Summary

Installation

Step 1 Check Equipment

Verify unit contents and check for damage upon arrival.

Step 2 Mount Unit

Instructions for mounting the fan coil unit in various orientations.

Step 3 Air Ducts

Connect supply-air and return-air ducts to the unit, ensuring proper sealing.

Step 4 Electrical Connections

Detail low-voltage and line-voltage wiring procedures, adhering to codes.

Step 5 Refrigerant Tubing Connection and Evacuation

Connect refrigerant lines and evacuate the system to 500 microns.

Step 6 Refrigerant Flow-Control Device

Discusses piston and TXV devices, including replacement and installation.

Step 7 Condensate Drains

Proper installation of condensate drains and traps to prevent water damage.

Step 8 Accessories

Instructions for installing optional accessories like humidifiers.

Step 9 Sequence of Operation

Explains the unit's operation modes: continuous fan, cooling, and heating.

This document provides installation instructions for FB4CNF, FB4CNP, and FX4D fan coil units, which are designed for R-410A refrigerant systems ranging in size from 018 to 061. These units are built for installation flexibility and are compliant with low leak requirements, exhibiting less than 2% cabinet leakage rate at 0.5 inches W.C. and 1.4% cabinet leakage rate at 0.5 inches W.C. when tested according to ASHRAE 193 standard.

Function Description:

The fan coil units are designed to provide cooling and heating (when paired with a heat pump or electric heater) for residential and manufactured/mobile home applications. They circulate air through an evaporator coil, which either cools and dehumidifies the air (cooling mode) or transfers heat to the air (heating mode). The units are compatible with R-410A refrigerant, a common choice for modern HVAC systems.

Important Technical Specifications:

Refrigerant: R-410A.
Sizes: 018 to 061, corresponding to nominal cooling capacities from 18,000 to 60,000 BTUh.
Metering Devices:
- FB4CNF(018-048) models use a refrigerant piston metering device.
- FB4CNP and FX4D(018–061) models use a TXV (Thermostatic Expansion Valve).
Motor: Multi-tap ECM (Electronically Commutated Motor) for enhanced efficiency.
Leakage Rate: Less than 2% cabinet leakage at 0.5 inches W.C. and 1.4% cabinet leakage at 0.5 inches W.C. (ASHRAE 193 compliant).
Heater Packages: Factory-authorized, field-installed electric heater packages are available in sizes from 5 to 30kW.
Electrical: 208/230V power leads. Transformer is factory-wired for 230V operation, with provisions for 208V applications. Low voltage circuit is protected by a 3 amp automotive type fuse.
Ductwork Clearance: Units with 20-30kW electric heaters require a 1-inch (25 mm) clearance to combustible materials for the first 36-inches (914 mm) of supply duct.
Condensate Drains: Primary and secondary 3/4-inch FPT drain connections.
Airflow Performance: Detailed tables (Table 1, 4, 5) provide CFM values at various external static pressures and motor tap settings for both dry and wet coil conditions.
Static Pressure Drop: Tables are provided for factory-installed filters (Table 2) and electric heaters (Table 3).
Motor Speed Taps: Five speed taps (Low, Medium, High, Electric Heat, Max+) with varying blower off time delays (90 seconds for taps 1-3, 0 seconds for taps 4-5).

Usage Features:

Installation Flexibility: Designed for upflow, downflow (kit required), and horizontal orientations.
Manufactured and Mobile Home Applications: Specifically designed for these applications, with particular wiring requirements for heat pump systems with outdoor thermostats.
Modular Design: Components can be disassembled and moved separately for installation in confined spaces, then reassembled.
Air Filter: Requires a field-supplied air filter. Factory-authorized filter kits are available for internal filter placement, or a field-supplied filter can be installed in the return duct system.
Control System: Low voltage connections for thermostat, unit, and outdoor equipment. Supports cooling-only, cooling and 1-stage heat, heat pump (cooling and 2-stage heat with/without outdoor thermostat), and electric heat/emergency heat modes.
Humidifier Integration: Wiring layouts provided for connecting a humidifier and humidistat to the fan coil unit.
R-410A Refrigerant Handling: Specific guidelines for R-410A, including higher operating pressures, rose-colored cylinders, 400 psig recovery cylinder service pressure rating, liquid refrigerant charging, 700 psig high side/180 psig low side manifold sets, HFC leak detectors, compatibility with POE oils, and requirements for liquid-line filter driers (rated for 600 psig, not in line longer than 72 hours).

Maintenance Features:

Filter Replacement/Cleaning: Recommended monthly.
Periodic Maintenance: Essential for high performance and minimizing equipment failure. Users are advised to consult a local dealer for maintenance contracts if they lack the necessary mechanical skills and tools.
Access Panels: Minimum 24-inch (610 mm) clearance from access panels is recommended for servicing.
Condensate Pan: Requires proper installation of primary and secondary drain lines with traps to ensure optimum drainage and prevent property damage. In some cases, a field-supplied secondary condensate pan may be required.
Evacuation: Coil and field-supplied tubing must be evacuated to 500 microns before opening outdoor unit service valves.
Piston Replacement: If required, the indoor piston must match the outdoor piston size. A back-up wrench is recommended when changing the piston.
Air Leak Prevention: Grommets for liquid and suction tubes, and proper caulking around drain lines and pan fittings, are crucial for maintaining low air leak performance and preventing cabinet sweating.