Trane 4TTR7 Series - User Manual

Installer’s Guide
October 2020
18-AC94D1-4C-EN
SAFETY WARNING
Only qualified personnel should install and service the equipment. The installation, starting up, and servicing of heating, ventilating,
and air-conditioning equipment can be hazardous and requires specific knowledge and training. Improperly installed, adjusted or
altered equipment by an unqualified person could result in death or serious injury. When working on the equipment, observe all pre-
cautions in the literature and on the tags, stickers, and labels that are attached to the equipment.
4TTR7024A
4TTR7036A
4TTR7048A
4TTR7060A
Note: “Graphics in this document are for representation only.
Actual model may differ in appearance.”
Condensing Units
4TTR7

Summary

Section 1. Safety

Installer Qualifications and General Precautions

Emphasizes installer background and general safety practices.

Refrigerant Safety and Handling

Covers R-410A, pressure, liquid line valve, and POE oil.

Electrical Safety Warnings

Focuses on hazards of working with live electrical components.

Component Handling Cautions

Addresses specific component risks like hot compressor domes.

Section 2. Unit Location Considerations

Refrigerant Piping Limits

Specifies maximum total and vertical refrigerant line lengths.

Suggested Locations for Reliability

Covers clearance, noise, airflow, and condensation avoidance.

Cold Climate Installation Notes

Addresses snow accumulation and unit elevation.

Coastal Installation Considerations

Details requirements for saltwater environments.

Section 3. Unit Preparation

Initial Unit Inspection and Unpacking

Steps for checking damage and removing from pallet.

Section 4. Setting the Unit

Support Pad Installation Guidelines

Requirements for concrete slabs and leveling.

Section 5. Refrigerant Line Considerations

Line Sizes and Valve Connections

Details standard and alternate line/valve sizes.

Factory Charge and Verification

Explains initial charge and verification methods.

Required Refrigerant Line Length and Lift

Instructions for determining line length and vertical change.

Refrigerant Line Insulation Requirements

Importance and method of insulating lines.

Reusing Existing Refrigerant Lines

Precautions for retrofit installations.

Section 6. Refrigerant Line Routing

Routing Precautions and Isolation

Guidance on minimizing noise and proper support.

Section 7. Refrigerant Line Brazing

Brazing Procedure Steps

Detailed steps for brazing refrigerant lines.

Section 8. Refrigerant Line Leak Check

Leak Detection Procedure

Steps for pressurizing and checking for leaks.

Section 9. Evacuation

Evacuation Procedure and Target Vacuum

Steps for achieving system vacuum.

Section 10. Service Valves

Opening Gas Service Valve

Procedure for opening the gas service valve.

Opening Liquid Service Valve

Procedure and safety warning for liquid valve.

Section 11. Electrical - Low Voltage

Low Voltage Wire Length Limits

Table specifying maximum wire lengths.

Low Voltage Hook-up Diagrams

Wiring diagrams for different control systems.

Section 12. Electrical - High Voltage

High Voltage Power Supply Requirements

Safety and code compliance for power supply.

High Voltage Disconnect and Grounding

Installation of disconnect and grounding.

Section 13. Start Up

System Start-Up Procedure

Step-by-step guide to initiating system operation.

Section 14. System Charge Adjustment

Temperature Measurement for Charging

Guidelines for measuring temps for subcooling/weigh-in.

Subcooling Charging in Cooling (Above 55°F)

Method for charging in warmer conditions.

Weigh-In Charging Below 55°F

Method for charging in cooler conditions using weight.

Section 15. Checkout Procedures and Troubleshooting

Operational Checkout List

Checklist for final system verification.

System Faults Troubleshooting Guide

Table of common faults and their causes.

Overview

1. Function Description
2. Usage Features
3. Maintenance Features

This document is an installer's guide for Trane Condensing Units, specifically models 4TTR7024A, 4TTR7036A, 4TTR7048A, and 4TTR7060A. It provides comprehensive instructions for the safe and proper installation, start-up, and maintenance of these outdoor air conditioning units. The guide emphasizes safety, proper handling of refrigerants, and electrical procedures to ensure optimal performance and longevity of the equipment.

Function Description

The Trane Condensing Units (4TTR7 series) are outdoor components of a central air conditioning system. Their primary function is to condense refrigerant gas into liquid, releasing heat to the outdoor environment. This process is crucial for cooling indoor spaces when paired with an indoor evaporator coil and air handler. These units are designed to operate with R-410A refrigerant, a high-pressure refrigerant that requires specific handling procedures and approved service equipment. The guide details the steps for connecting the outdoor unit to the indoor unit via refrigerant lines, ensuring a sealed and properly charged system. It also covers the electrical connections necessary for the unit's operation, including low voltage wiring for thermostat control and high voltage power supply.

Usage Features

The installation process for these condensing units involves several key stages, each with specific usage features and considerations:

• Unit Location: The guide provides recommendations for optimal unit placement to ensure best reliability and minimize noise or vibration transmission to the building structure. This includes maintaining adequate clearance around the unit for airflow and service access, avoiding locations near bedrooms or windows where defrost vapor might be annoying, and positioning the unit away from excessive roof runoff. For cold climates, specific precautions are outlined, such as elevating the unit to allow for snow and ice drainage and installing snow drift barriers.
• Refrigerant Piping: Detailed instructions are given for refrigerant line considerations, including maximum total line length and vertical lift limits. The guide specifies the correct line sizes and service valve connection sizes for various models. It also emphasizes the importance of insulating the vapor line and preventing direct metal-to-metal contact between the liquid and vapor lines. For existing refrigerant lines, precautions are listed to ensure they are brazed (not soldered), correctly sized, and free of leaks, acid, and oil.
• Refrigerant Line Routing: To prevent noise and vibration transmission, the guide advises using isolation-type hangers when fastening refrigerant lines to building structures and insulating lines that run through walls or sills. Minimizing 90-degree turns is also recommended for efficient routing.
• Brazing Procedures: The guide provides a step-by-step process for brazing refrigerant lines, including deburring pipe ends, cleaning surfaces, removing valve cores, purging with dry nitrogen, and wrapping valve bodies with wet rags to prevent heat damage. It also highlights the importance of checking the directional flow arrow on field-installed external driers.
• Leak Check and Evacuation: Before opening service valves, a thorough leak check using dry nitrogen and a soapy solution is required. Following this, the refrigerant lines and indoor coil must be evacuated to a specific micron level (no higher than 350 microns) to remove moisture and non-condensables, ensuring system integrity.
• Service Valve Operation: Instructions are provided for safely opening both the gas and liquid service valves. Extreme caution is advised when opening the liquid line service valve to prevent abrupt release of system charge.
• Electrical Connections: The guide includes detailed low voltage hook-up diagrams for various thermostat and air handler configurations (e.g., TEM6, TAM7, Variable Speed UH2/DH2-V, S-Series Furnace). It also specifies maximum wire lengths for different wire sizes. For high voltage, it stresses the importance of installing a separate disconnect switch, using flexible electrical conduit to minimize vibration noise, and grounding the unit according to national, state, and local codes.
• System Start-Up: A sequence of steps for system start-up is provided, including setting the thermostat to OFF, applying power, and waiting a specified period (one hour if a crankcase heater is used and ambient temperature is below 70°F) before setting the thermostat to ON.

Maintenance Features

The installer's guide also touches upon aspects that contribute to the long-term maintenance and proper functioning of the unit:

• System Charge Adjustment: This is a critical maintenance feature, ensuring the system has the correct amount of refrigerant for optimal performance. The guide outlines two methods:
  • Subcooling Charging (Above 55°F Outdoor Temp.): This is the recommended method for charging in cooling mode when outdoor ambient temperatures are above 55°F. It involves measuring liquid line temperature and pressure, and using a subcooling chart to determine the correct liquid gage pressure based on the unit's design subcooling value, refrigerant line length, and lift. Adjustments are made by adding or recovering refrigerant until the measured values match the chart.
  • Weigh-In Method (Below 55°F Outdoor Temp.): For outdoor temperatures below 55°F, the weigh-in method is recommended. This involves calculating the additional refrigerant needed based on the length of interconnecting tubing beyond the factory-charged 10 feet, using a charge multiplier (0.6 oz/ft). This method is also suitable for initial installations or when replacing a system charge.
• Stabilization Period: After any charge adjustment or at startup, the system must be operated for a minimum of 20 minutes to stabilize before accurate measurements can be taken. This ensures reliable performance data.
• Checkout Procedures and Troubleshooting: The guide includes a comprehensive checklist for operational and checkout procedures. This involves verifying leak-free refrigerant lines, proper insulation, secure connections, unobstructed airflow, and smooth outdoor fan operation. It also instructs installers to operate the complete system in each mode to ensure safe operation. A detailed troubleshooting chart is provided, categorizing system faults into "Refrigerant Circuit," "Electrical," and "Defrost" issues, with primary and secondary causes listed for each symptom. This chart is an invaluable tool for diagnosing and resolving common problems, facilitating efficient maintenance and repair.
• Unit Inspection: A final unit inspection is recommended to ensure factory tubing has not shifted during shipment and that tubes do not rub against each other. Wiring connections must also be tight and properly secured.

By following these detailed instructions, installers can ensure that the Trane Condensing Units are installed, started up, and maintained to deliver reliable and efficient cooling performance.

Trane 4TTR7 Series Specifications

General

Refrigerant	R-410A
Sound Level	As low as 72 dB
Cooling Capacity (BTU/h)	18, 000 - 60, 000
Heating Capacity (BTU/h)	18, 000 - 60, 000
Type	Heat Pump
Warranty	10 Year Limited Warranty on compressor, 10 Year Limited Warranty on outdoor coil
Stages	Single Stage