Evaporator Frost Control; Phase Monitor - Trane RT-SVX38C-EN Installation, Operation And Maintenance Manual

Wireless Zone Sensor (BAYSENS050)
This electronic sensor features five system settings (Auto,
Off, Cool, Heat, and Emergency Heat) as well as On and
Auto fan settings. It is a manual or auto changeover control
with dual setpoint capability. Other features include a
timed override function, lockable system settings, and
Fahrenheit or Celsius temperature display. Included with
the wireless zone sensor is a receiver that is to be mounted
inside the unit, a mounting bracket, and a wire harness.
High Temperature Sensor (BAYFRST001*)
This sensor connects to the RTRM emergency stop input
on the LTB and provides high limit "shutdown" of the unit.
The sensor is used to detect high temperatures due to a
high thermal event in the air conditioning or ventilation
ducts. The sensor is designed to mount directly to the
sheet metal duct. Each kit contains two sensors. The return
air duct sensor (X1310004001) is set to open at 135ºF . The
supply air duct sensor (X1310004002) is set to open at
240ºF . The control can be reset after the temperature has
been lowered approximately 25ºF below the cutout
setpoint.

Evaporator Frost Control

ReliaTel™ Option
This input incorporates the Frostat™ control (FOS)
mounted in the indoor coil circuit and can be activated by
closing a field-supplied contact installed in parallel with
the FOS.
If this circuit is open before the compressor is started, the
compressor will not be allowed to operate. Anytime this
circuit is opened for 1 continuous second during
compressor operation, the compressor for that circuit
immediately turns off. The compressor will not be allowed
to restart for a minimum of 3 minutes if the FOS closes.
Discharge Line Temp Switch (DLTS)
The DLTS is looped in series with HPC and LPC. It prevents
compressor from overheating (over 300Fº dome temp) in
case of indoor fan failure (cooling) or outdoor fan failure
(heating).

Phase Monitor

This sensor monitors voltage between the 3 conductors of
the 3-phase power supply. Two LED lights are provided:
• The green light indicates that a balanced 3-phase
supply circuit is properly connected.
• The red light indicates that unit operation has been
prevented. There are two conditions that will prevent
unit operation:
• The power supply circuit is not balanced with the
proper phase sequence of L1, L2, L3, for the 3
conductors of a 3-phase circuit.
• The line to line voltage is not between 180 volts and
633 volts.
RT-SVX38C-EN
General Information
9