Micro-Air, Inc.
Page 13
EasyTouch 2.5 Operations Manual
Rev 1.0 8/27/14
on again) via the Power button on the Home or Main display screens. The fault count being monitored for
lockout will be reset to zero upon the termination of the cooling or heating cycle, or if power is cycled.
NOTE:
The Air Sensor Fault results in an immediate lockout condition.
9.1 Air Sensor Fault (DX & CW, immediate lockout)
Displayed as “SENSOR FAULT”
The EasyTouch can utilize one of 3 different temperature sensors for its Inside Temperature display
and use for control purposes:
Built-in Display Temperature Sensor
Alternate Air Temperature sensor plugged into the main FX1/FX2 control board
Intake Combination Temperature/Humidity sensor pulled into the FX2 Humidity Option Board (if
equipped)
Normally, the inside temperature sensor selection is determined automatically. (See section 11.1.19
for details on how to select the Inside Temperature sensor.) If a specific sensor is selected and it
malfunctions, or all of the potential inside temperature sensors have malfunctioned, the Air Sensor
Fault will be declared. Depending on which temperature sensor is required, replacing the failed
external temperature sensors or replacing the display itself may be necessary to remedy the problem.
9.2 High Pressure Fault (DX only, contributes to lockout count)
Displayed as “HIGH PRES FAULT”
The High Pressure Fault
occurs whenever the system’s high pressure switch opens during
compressor operation or whenever it is open just before compressor start-up.
1. If the high pressure switch is open while the compressor is off, the most likely cause is an open
connection in the pressure switch itself.
2. If the high pressure switch opens while the compressor is operating in COOL mode, the most
likely cause is poor seawater flow or a fouled condenser.
3. If the high pressure switch opens while the compressor is operating in HEAT mode, the most
likely cause is poor air flow through the evaporator, possibly due to a clogged air filter.
9.3 Low Pressure Fault (DX only, contributes to lockout count)
Displayed as “LOW PRES FAULT”
The Low Pressure Fault occurs whenever the system’s low pressure switch opens during compressor
operation and remains open for at least 10 minutes, or whenever it is open just before compressor
start-up.
1. If the low pressure switch is open while the compressor is off, the most likely cause is loss of
refrigerant charge in the system due to a leak.
2. If the low pressure switch is open while the compressor is operating in COOL mode, the most
likely causes are low refrigerant charge or cold seawater.
3. If the low pressure switch is open while the compressor is operating in HEAT mode, the most
likely causes are low refrigerant charge or cold inside air temperature. Setting the fan speed to
manual low can sometimes remedy low pressure faults in HEAT mode.
9.4 Low AC Fault (DX Only, no lockout)
Displayed as “LOW AC FAULT”
The Low AC Fault occurs whenever the AC line voltage is below the
Low-Voltage Monitor
parameter
setting during compressor operation for at least 5 minutes, or whenever it is below just before
compressor start-up. By default, the Low-Voltage monitor is not enabled. See section 11.2.3 for
more information on how to enable and set the voltage threshold for the Low-Voltage Monitor.
