Tranquility
®
Fluid Cooler – 60 Hz
R e v. : F e b r u a r y 2 2 , 2 0 2 2
G e o t h e r m a l H e a t i n g a n d Co o l i n g
26
AXM Controls
Low Water Temperature Cutout Selection
The AXM control allows the field selection of low water
(or water-antifreeze solution) temperature limit by
clipping the jumper wire between GND and CO, which
changes the pump and fan operation associated with
the entering air temperature (EAT) sensor. Note that
the EAT thermistor is located on the coil face near the
control box.
The factory setting for is for systems using water 40°F
[4.4°C]. In low ambient temperature applications with
antifreeze, the jumper wire between GND and CO
should be clipped as shown in Figure 14 to change the
setting to 25°F [-3.9°C].
Figure 14: Low Temperature Limit Jumper
Stand-Alone Operation
When the DIP S1-1 has been placed into the OFF
position the unit will operate with following logic to
operate the fan when:
1. The EAT is greater than 40°F when the freeze
protection is set for water or 25°F when set for
antifreeze and
2. The flow switch input (W) is closed with a flow
switch option or there is the presence of a (Y1)
compressor input with a loop pump option.
The unit fan speed will operate in low speed when
the entering water temperature (EWT) is less than
70°F in cooling and greater than 60°F in heating. The
fan speed will then vary depending on EWT and EAT
conditions until the EWT is greater than 120°F in cooling
or less than 45°F in heating where the fan will operate
continuously at high speed.
Hybrid Operation
When the DIP S1-1 has been placed into the ON
position the unit will operate with logic to operate the
fan in high speed when:
1. The EAT is greater than 40°F when the freeze
protection is set for water or 25°F when set for
antifreeze and
2. The temperature difference (EWT – EAT) must be
greater than 2°F and
3. The EWT is greater than 45°F and
4. The flow switch input (W) is closed with a flow
switch option or there is the presence of a (Y1)
compressor input with a loop pump option.
Freeze Protection Operation:
The operation for freeze protection monitors the EAT
sensor. When the ambient temperature measured by
the EAT sensor is below the current freeze protection
setpoint the outdoor fan operation will stop. In addition,
if the unit comes with the loop pump option the loop
pump output will be operated based on the ambient
temperature, measured using entering air temperature
sensor (T2).
If the compressor input is inactive, and the ambient
temperature measured by the entering air temperature
sensor is below the current Freeze Protection Setpoint,
the loop pump output will be activated. Once the entering
ambient temperature rises above the Freeze Protection
Setpoint, the loop pump output will be de-activated.
Table 7: LED Operations
Description of Operation
Status
LED
Fault LED
TFC Control is non-functional
Off
Off
Normal Operation - no active communications
with blower
On
On
Normal Operation - active communications
with blower
On
Very Slow
Flash
EWT out of range
Off
Fast Flash
EAT out of range
Off
Fast Flash
Blower Fault
Off
Fast Flash
Freeze Protection Active
Fast Flash
On
Very Slow Flash – 1 flash every five seconds (1 second on, 4 second off)
Slow Flash – 1 flash every two seconds (1 second on, 1 second off)
Fast Flash – 2 flashes per second (¼ second on, ¼ second off)
