Alarm Description; Alarm Listing; Table 6: Alarms Listing - Riello NXHP Series Installation, Operation And Maintenance Instructions

6 - ALARM DESCRIPTION

6.1 - Alarm listing

The following tables of alarms list their probable cause and the likely effect on the unit, as well as the reset type. Proposed investigations
and corrective actions shall be performed by fully qualified technician.
Description
1 EWT sensor failure
LWT sensor failure
2
Refrigerant Temperature (TR) sensor
3
failure
4 OAT sensor failure
DHW_TT sensor failure
5
6 CHWSTEMP sensor failure
10 Discharge Temperature (TD) sensor failure
Air Exchanger Temperature (TE) sensor
11
failure
Suction Temperature (TS) Sensor failure
14
TE & TS sensors wrongly connected or
16
PMV failure
Suction Pressure transducer failure
17
20 Loss of communication with UI
Loss of communication with Inverter
21
23 Loss of communication with Slaves
Loss of communication with Master
24
Loss of communication with Jbus Master
25
31 Safety Input
32 Flow Switch failure
33 High Pressure Switch failure
Leak detection alarm
40
41 Low Superheat failure
Compressor not started
42
43 Drive unconfigured
44 Four-way Valve failure
45 Lower Fan not started
Upper Fan not started
46
66

Table 6: Alarms listing

Reset type
When value returns within correct
Continue X
range
When value returns within correct
Stop X
range
When value returns within correct
Cpr stop X
range
When value returns within correct
Continue X
range
DHW When value returns within correct
X
Failed range
When value returns within correct
X
range
X Error becomes definite after
Stop X
retrying operation for 4 times.
Error becomes definite after
Stop X X
retrying operationfor 4 times.
Error becomes definite after
Stop X X
retrying operation for 4 times.
X Error becomes definite after
Stop X
retrying operation for 4 times.
X Error becomes definite after
Stop X
retrying operation for 4 times.
When a new message is
Continue X
received from the UI
When a new message is
Stop X
received from the Inverter
Master
X
continues
Stop X
When a new valid message is
Stop X
received from the Jbus Master
Stop X When Safety Input is closed
X Error becomes definite after
Stop
retrying operation for 5 times.
Error becomes definite after
Stop X
retrying operation for 3 times.
When value returns within correct
X
range
When value returns within correct
Stop X
range
Stop X
Stop X Drive configuration completed
When value returns within correct
Stop X
range
Power cycle after more than 5
Stop X
occurrences in 1 hour
Power cycle after more than 5
Stop X
occurrences in 1 hour
Investigation / corrective actions
Comment
1. Check EWT sensor (EWT).
2. Check NHC board.
1. Check LWT sensor (LWT).
2. Check NHC board.
1. Check TR sensor (TR).
2. Check NHC board.
1. Check Additional OAT sensor (OAT).
2. Check NHC board.
1. Check DHW sensor (DHW_TT).
2. Check NHC board.
1. Check CHWSTEMP sensor
(CHWSTEMP).
2. Check NHC board.
1. Check discharge temp. sensor (TD).
2. Check inverter connection
1. Check temp. sensor (TE).
1. Check suction temp. sensor (TS).
1. Check temp. sensor (TE, TS)
2. Check PMV (expansion valve)
electrical connexion
1. Check suction pressure. sensor (PS).
1. Ensure that water flow rate is
sufficient and fan operation is normal
2. Check PMV operation
3. Check high pressure switch electrical
connection
1. Stop and disconnect the unit
2. Check compressor connection
1. Check operation of 4-way valve
2. Check 4-way valve coil and
connection
3. Check TE, TS, TR, EWT and OAT
sensors
1. Stop and disconnect the unit
2. Check fan motor connection
3. Check if impeller is not blocked
1. Stop and disconnect the unit
2. Check fan motor connection
3. Check if impeller is not blocked