Trane A5HP4 - User Manual

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88-A5HP4001-1A-EN

ALL phases of this installation must comply with NATIONAL, STATE AND LOCAL CODES

IMPORTANT – This Document is customer property and is to remain with this unit. Please return to service informa-

tion pack upon completion of work.

These instructions do not cover all variations in systems or provide for every possible contingency to be met in connection with

the installation. Should further information be desired or should particular problems arise which are not covered sufficiently for the

purchaser’s purposes, the matter should be referred to your installing dealer or local distributor.

Note: The manufacturer recommends installing only approved matched indoor and outdoor systems. All of the manufacture’s split

systems are A.H.R.I. rated only with TXV/EEV indoor systems. Some of the benefits of installing approved matched indoor and

outdoor split systems are maximum efficiency, optimum performance and the best overall system reliability.

Table of Contents

Section 1. Safety ..................................................................................... 2

Section 2. Unit Location Considerations.............................................. 4

Section 3. Unit Preparation .................................................................... 5

Section 4. Setting the Unit ..................................................................... 5

Section 5. Refrigerant Line Considerations ......................................... 6

Section 6. Refrigerant Line Routing ..................................................... 7

Section 7. Refrigerant Line Brazing ...................................................... 8

Section 8. Refrigerant Line Leak Check ............................................... 9

Section 9. Evacuation ............................................................................. 9

Section 10. Service Valves ..................................................................... 9

Section 11. Electrical - Low Voltage ................................................... 10

Section 12. Electrical - High Voltage .................................................. 11

Section 13. Start Up .............................................................................. 12

Section 14. System Charge Adjustment ............................................. 12

Section 15. Checkout Procedures ....................................................... 16

Section 16. Defrost Control ................................................................. 17

Section 17. Troubleshooting ................................................................ 20

Section 18. Wiring Diagrams ............................................................... 22

Section 19. Pressure Curves ............................................................... 27

Section 20. Refrigerant Circuit (only for reference)........................... 32

Heat Pumps

A5HP4

Installation and Operation Manual

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This document is an Installation and Operation Manual for Heat Pumps, specifically the A5HP4 series. It provides comprehensive instructions for the proper installation, startup, and maintenance of these units, emphasizing compliance with national, state, and local codes.

Function Description:

The A5HP4 series heat pumps are designed for residential heating, ventilating, and air-conditioning (HVAC) applications. They operate as split systems, requiring both an outdoor condensing unit and an indoor evaporative coil. The units are factory charged with R-454B refrigerant and are designed to work with TXV/EEV indoor systems for optimal efficiency and performance. The manual details procedures for both cooling and heating cycles, including specific instructions for refrigerant line installation, leak checking, evacuation, and system charging. A key feature is the demand defrost control, which measures outdoor ambient and coil temperatures to determine the need for defrost cycles, optimizing the heat pump's operation in colder climates.

Important Technical Specifications:

Refrigerant Type: R-454B (flammable refrigerant). Proper service equipment and handling procedures are required.
Operating Range (Cooling): 55°F - 120°F.
Unit Dimensions and Weight:
- A5HP4018D, A5HP4024D, A5HP4030D: 33 x 30 x 33 inches, 174 lbs (estimated uncrated).
- A5HP4036D: 37 x 34 x 37 inches, 199 lbs (estimated uncrated).
- A5HP4042D, A5HP4048D, A5HP4060D: 45 x 34 x 37 inches, 250-251 lbs (estimated uncrated).
Refrigerant Line Limits:
- Maximum TOTAL length: 150 feet (including lift).
- Maximum vertical change: 50 feet.
Service Valve Connection Sizes: Vary by model, but typically include 5/8", 3/4", or 7/8" for the vapor line and 5/16" or 3/8" for the liquid line. Alternate connection sizes are also provided.
Low Voltage Wiring:
- 18 AWG: Max. 150 Ft.
- 16 AWG: Max. 225 Ft.
- 14 AWG: Max. 300 Ft.
Defrost Termination Temperatures:
- As Shipped (>22°F outdoor): 47°F.
- With Jumper J2 cut (>30°F outdoor): 47°F.
- With Jumper J2 cut (6°F-30°F outdoor): 70°F.
- Below 6°F outdoor: 12 min. or 35°F every 3 hrs.
Low Ambient Heat Pump Lock Out: -12°F.
Low Ambient Heat Pump Resume: -3°F.
LPCO Bypass In/Out Defrost: 3 minutes.
SOV Switch-Over Delay after Defrost Term.: 12 seconds.

Usage Features:

Installation Flexibility: The manual provides guidelines for unit placement, including clearances from walls, shrubbery, and other structures, as well as considerations for roof mounting and cold climates (e.g., elevating units to prevent snow accumulation).
Refrigerant Line Management: Detailed instructions for routing, brazing (not soldering), and insulating refrigerant lines are provided to prevent noise transmission and ensure system integrity.
System Start-Up: A step-by-step process for initial system startup, including waiting periods for compressor crankcase heater activation in cold ambients.
System Charge Adjustment: Comprehensive guidance for charging the system using subcooling (for outdoor temperatures above 55°F) or the weigh-in method (for outdoor temperatures below 55°F or initial installations). Pressure curves are provided for various models to aid in accurate charging.
Defrost Control: The unit features a demand defrost control that uses ambient and coil temperature sensors to optimize defrost cycles. It also includes selectable termination temperatures (47°F or 70°F) and various fault detection mechanisms indicated by LED flashes.
Troubleshooting: Flowcharts are included to assist in diagnosing common issues such as a compressor failing to start or problems with the outdoor TXV/heating mode.
Wiring Diagrams: Detailed low and high voltage wiring diagrams are provided for various indoor unit combinations (A5AH6, A5AH4, 5TAM5, Furnace with Evaporator Coil MCB) and outdoor unit models (018A, 024A, 030A, 036A, 042A, 048A, 060A).

Maintenance Features:

Leak Checking: Instructions for pressure testing with nitrogen and vacuum testing to ensure the integrity of refrigerant lines. Acceptable leak detection methods include electronic leak detectors calibrated for R454B and the bubble method.
Evacuation: Procedures for evacuating refrigerant lines and indoor coils to a specified micron level (no higher than 350 microns).
Service Valve Operation: Detailed steps for opening and closing both gas and liquid service valves, emphasizing caution when opening the liquid line service valve to prevent abrupt charge release.
Checkout Procedures: A comprehensive checklist for verifying proper installation and operation, including refrigerant line integrity, insulation, airflow settings, and overall system functionality in each mode.
Sensor Testing: Instructions for measuring the resistance of ambient and coil temperature sensors using an ohmmeter and comparing values to a provided thermistor table to verify sensor functionality.
Fault Code Diagnostics: A table of LED fault codes and their descriptions, along with corresponding defrost control behavior, to assist in identifying and resolving system issues. For example, 1 flash indicates an ambient temp sensor out of range, leading to defrost every 60 minutes. 2 flashes indicate a coil temp sensor out of range, leading to a 15-minute forced defrost every 60 minutes. 3 flashes indicate an open low pressure switch.