Troubleshooting - Toshiba Estia RUA-CP1701H Installation Manual

Monobloc Outdoor Unit

14.0 Troubleshooting

Fault Symptoms:
Symptom
Room is not heated or
cooled. Water is not hot
enough.
Nothing is displayed on
the remote controller.
Flow rate switch is
activated.
Hot water leaks from
pressure relief valve.
Alarm Listing
Check Code
Operational Cause
- 1 EWT sensor failure
- 2 LWT sensor failure
Refrigerant Temperature (TR) sensor
- 3
failure
- 4 OAT sensor failure
- 5 DHW_TT sensor failure
- 6 CHWSTEMP sensor failure
- 7 IAT sensor failure
- 8 RC indoor temperature failure
Possible Cause
Incorrect remote controller setting
Incorrect Parameter setting
Backup heater disconnected
Insufficient capacity
Sensor defect
Power is not supplied.
Incorrect setting
Air trapped in the pump
Low hydraulic pressure
Strainer is clogged.
Large resistance on the heating
circuit side
Malfunction of motorized 3-way valve
for hot water supply
Excessive hydraulic pressure
Insufficient capacity of expansion
tank
Expansion tank failure
Diagnostic functional operation
Unit Status
Continue
Stop
Compressor stop
Continue
DHW failed
Continue
Continue
Check remote controller operation and temperature setting
Check Parameter setting with the Parameter table.
Check backup heater installation and set up
Check selection of equipment.
Check whether temperature sensor is installed at the normal position.
Check power supply wiring.
Check the setting with the Parameter table.
Release air completely according to the procedure.
Set hydraulic pressure considering pipe height, and replenish water until
manometer shows a value of set hydraulic pressure or more.
Clean the strainer.
Install larger diameter water pipe work or adopt a bypass valve.
Check wiring and parts.
Set hydraulic pressure considering pipe height, and replenish water until
manometer shows a value of set hydraulic pressure or more.
Check expansion tank capacity compared to total water amount. If it is
insufficient, install another expansion tank.
Check the air pressure in expansion tank.
Replace expansion tank
Automatic
Reset
Automatic reset when the sensor returns within the correct range.
X 1. Check EWT sensor (EWT)
2. Check NHC board
Automatic reset when the sensor returns within the correct range.
X 1. Check LWT sensor (LWT)
2. Check NHC board
Automatic reset when the sensor returns within the correct range.
X 1. Check TR sensor (TR)
2. Check NHC board
Automatic reset when the sensor returns within the correct range.
X 1. Check additional OAT sensor (OAT)
2. Check NHC board
Automatic reset when the sensor returns within the correct range.
X 1. Check DHW sensor (DHW)
2. Check NHC board
Automatic reset when the sensor returns within the correct range.
X 1. Check CHWSTEMP sensor (CHWSTEMP)
2. Check NHC board
Automatic reset when the sensor returns within the correct range.
X 1. Check IAT sensor (IAT)
2. Check NHC board
Automatic reset when the sensor returns within the correct range.
X 1. Check RC indoor temperature sensor
2. Check NHC board
88
Installation Manual
Corrective Action
Determination and action