Tranquility
®
D i g i t a l ( D X M 2 ) — Tr o u b l e s h o o t i n g G u i d e
R e v. : 1 0 M a r c h , 2 0 1 5
8
G e o t h e r m a l H e a t i n g a n d C o o l i n g
Continued
Configure
No
See Lockout
Faults on page
51 under ‘Fault
Codes’
Is there more
than one unit
sharing a
common loop?
No
Properly configure
unit. See Section 3.3
and Section 3.4 on
page 57.
Does this unit
have a Variable
Speed Pump and
is it configured for
parallel pumping?
No
Yes
Yes
Yes
Is the thermostat
configured for the proper
model of the unit?
(Example: TZ036) This is
found on thermostat’s unit
configuration menu.
Yes
Yes
Does the unit have the
correct ECM Motor? Check
the ECM table, which is in
the unit’s IOM.Compare to
the motor in the unit.
Verify pump is
supplying enough flow
using Pressure Drop
Software. Closed loop
2.25 - 3.0 gpm per ton.
Replace with
correct motor
No
The unit
periodically
locks out on LT1
in heating or
high pressure in
cooling
ATC Thermostat
says ‘ECM
Configuration
Error’
The unit does
run but ATC
Thermostat
says ‘Service
Needed’
Yes
Troubleshooting Flow Chart
This is the Unit
Performance Sentinel. In
cooling mode if LT2 is 40°
or lower or LT1 is 125° or
greater. In heating mode if
LT2 is 125° or greater.
Go to Faults
Code 8.
A-F
Next Page
No
No
No
