District Heating; Diagnostics - Troubleshooting; General; Displaying Alarms - Carrier HSM User Manual

6.12.4 - Back-up heating using an electric boiler
The boiler is started based on the 'Back-up heating autho-
rised' information and controlled by a 0-10 V signal to
satisfy the temperature of loop 1, or the temperature of the
DHW tank if domestic hot water is needed.
6.12.5 - Back-up heating using a gas or oil-fired boiler
The boiler is started by the 'Back-up heating authorised'
information. Mixing valve SV31 is controlled by a 0-10 V
signal to satisfy the temperature of loop 1, or the temperature
of the DHW tank if domestic hot water is needed.

6.13 - District heating

The back-up heating is provided by district heating. Two
heat exchangers are installed, the first for heating and the
second for domestic hot water.
6.13.1 - Heat exchanger for loops 1 and 2
If the 'Back-up heating authorised' information is activated
(see chapter "Back-up heating"), temperature GT1 :3 is
controlled by valve SV21 via a 0-10 V signal to satisfy the
setpoint of loop 1 + an offset "d_hl_off".
A PI control loop is configured, and the proportional and
integral gains are adjustable in the DIS_CONF menu.
Valve SV31 is fully closed if back-up valve SV31 is closed
or if the "Back-up heating authorised" information is not
active.
6.13.2 - DHW heat exchanger
If the 'Back-up heating authorised' information is activated
(see chapter "Back-up heating"), temperature GT7 :2 is
controlled by valve SV27 via a 0-10 V signal to satisfy the
DHW setpoint.
A PI control loop is configured, and the proportional and
integral gains are adjustable in the DIS_CONF menu.
Valve SV37 is fully closed if the "Back-up heating authorised"
information is not active.
6.13.3 - Back-up valve
If the 'Back-up heating authorised' information is activated
and the district heating heat exchanger entering water
temperature is below the mixing bottle temperature (GT1 :4
< GT1 :2), back-up valve SV31 is limited to 95% opening.
en
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ENGLISH

7 - DIAGNOSTICS - TROUBLESHOOTING

7.1 - General

The Pro-Dialog+ control system has many fault tracing aid
functions. The local interface and its various menus give
access to all unit operating conditions. If an operating fault
is detected, an alarm is activated and an alarm code is
stored in the ALARMS menu, sub-menu ALARMRST.
No. Code Alarm description
Thermistor faults
1 Th-01 Fault, outside air temperature sensor (OAT/GT3)
2 Th-02 Fault, temperature sensor heating loop 1 tank (HL1_TT)
3 Th-03 Fault, water temperature sensor heating loop 1 (HL1_WT)
4 Th-04 Fault, water temperature sensor heating loop 2 (HL2_WT)
5 Th-05 Fault, DHW tank temperature sensor (DHW_TT)
6 Th-06 Fault, temperature sensor, additional DHW tank (DHW_TT2)
7 Th-07 Fault, DHW water temperature sensor (DHW_WT)
Th-08 Fault, DHW backup temperature sensor (DHW_BKWT)
8
9 Th-09 Fault, heat exchanger entering temperature sensor, district heating
(DIST_EWT)
10 Th-10 Fault, heat exchanger leaving temperature sensor, district heating
(DIST_LWT)
Communication fault
11 Co-HP Communication loss with the heat pump
12 Co-o1 Communication loss with slave board 1
13 Co-o2 Communication loss with slave board 2
Other faults
14 P-34 Heat pump fault
15 P-99 Anti-legionnella mode duration too long

7.2 - Displaying alarms

The alarm LED on the interface (see chapter 4.1) allows
immediate display of the unit status.
• A flashing LED shows that the circuit is operating but
there is an alert.
• A steady LED shows that the unit or one circuit has
been shut down due to a fault.
The ALARMRST menu on the interface displays up to
five fault codes that are active on the unit.

7.3 - Resetting alarms

When the cause of the alarm has been corrected the alarm
can be reset, depending on the type, either automatically
on return to normal, or manually when action has been
taken on the unit. Alarms can be reset even if the unit is
running. This means that an alarm can be reset without
stopping the machine. In the event of a power supply
interrupt, the unit restarts automatically without the need
for an external command.
However, any faults active when the supply is interrupted
are saved and may in certain cases prevent a circuit or a
unit from restarting.
A manual reset must be run from the main interface via
the ALARMRST menu, item RST_ALM. Depending on
the configuration in the GENCONF menu, access to the
item may be protected by a password.