DIGITAL Geothermal
Heat Pumps
TE/TZ/TES/TEP
97B0601N01
Rev.: 3/10/15
Tranquility
®
Digital (DXM2)
Troubleshooting Guide
Table of Contents
Introduction 2
Troubleshooting Flow Chart
3-9
Flow Chart Reference Symbols and Diagrams
10
Contactor Chart
12
Verifying Pump Feedback Signal
12
Removing Powerhead on Modulating Valve
13-14
Checking Compressors
15-16
Reversing Valve Touch Test Chart
17
Performance Troubleshooting
17-18
Functional Troubleshooting
20-22
Typical Split Water-to-Air Troubleshooting Form
23
Typical Water Source Refrigeration Circuit
24
(Heating Cycle)
Unit Operating Conditions
25
Basic Refrigeration Summary
26
Refrigeration Troubleshooting
27-28
Auxiliary Heat Check
29
Checking Pump Output
29
Compressor Contactor Voltage Check
30
Check CCH for 24 Volts
30
Verifying Contactor
30
Verifying Capacitor
31
Checking Pump Power Cord
31
Replacing Variable-Speed Pump Power Head
32
Verifying Power at Molded Plug
32
for Compressor
Verifying Antifreeze
33
Second Stage Verification
34
Verifying 24V at Reversing Valve
35
Checking Reversing Valve at DXM2
35
A0-2 Jumper
36
Checking for Power at DXM2
36
Verifying DC Voltage on DXM2 Board
37
for Modulating Valve Check
TXV Bulb Test
38
Verifying Dipswitch Position
39
Replacing High Pressure Water Switch
39
Verifying a Thermistor
40-41
Turning Breaker on in Panel or Aux Heat Control
42
Static Pressure Check
42
Locating Tstat Version and DXM2 Version
43
UltraCheck EZ
™
Motor Diagnostic Tool
43
Checking Dipswitches on DXM2
44
Magnet Test to Shift Reversing Valve
44
Checking Blower Line Voltage
45
Modulating Valve Loses Configuration
45
Hard Reset of Thermostat
46
Units Having LT1 Lockouts In Heating
47
Electrical—Power Wiring
48
LT2 Sensor Location for Non-TAH Air Handlers
49
Air Coil Connection
49
Lineset Diameters and Charge Information
49
Connection to Non-Communicating thermostat and
AXM communicating control in TAH Air Handler
50
Connection to Non-Communicating thermostat
and non-communicating Air Handler/Furnace
50
Definitions of Conditions
51-52
DXM2 Board Layout and Dipswitches
53
AXM Board Layout and Dipswitches
54
DXM2 Controls
55-58
Typical Wiring Diagrams
59-61
ATC32U02 Thermostat Screens and Set Up
62-68
Revision History
72
