MAXA i-MAX 0475 - Auxiliary Electric Heater

i-MAX Industrial inverter air/water heat pump with axial fans
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9.8 AUXILIARY ELECTRIC HEATER
In some configurations of some plant systems, it could be necessary the use an auxiliary electric heater for the system and/or
DHW sides.
To define the mode of using of the auxiliary electric heaters for plant system and DHW side, you must set the parameter “r24” as
below.
- r24=0 Auxiliary electric heaters not used;
- r24=1 Utilization only of the auxiliary electric heater of the plant side;
- r24=2 Utilization only of the auxiliary DHW electric heater;
- r24=3 Utilization of both auxiliary electric heaters of plant side and of domestic (sanitary) hot water production.
9.8.1 PLANT CIRCUIT AUXILIARY ELECTRIC HEATER
In alcune soluzioni impiantistiche può rendersi necessario l’utilizzo di una resistenza di integrazione per l’impianto.
If the temperature of regulation remains below the water setpoint in heating (Hea) - 0.5°C for a period of time equal to r12, the
auxiliary electric heater will be activated depending on the in joint or in substitution operation of the unit indicated in Paragraph
9.9. The electric heater turns off after reaching the setpoint (taking into account of an eventual offset set with the parameters r29
or r30 (see paragraph 9.10.6).
If the temperature of regulation remains less than water setpoint - r11(°C) and the unit is blocked that is caused by an error-
alarm, the electric heater will be activated. Then it will turn off when the lock-alarm is resolved.
In order to enable this function, you should enter into the page of parameters as follow PRGPSSPRG  (insert the maintainer
password)  PRG  PAr  PRG  CnF / rE.
Parameters
Unit
Value
Description
Terminals
Notes
H81 Num 22
Plant auxiliary electric heater
(Undervoltage output)
DO3E(phase)
DO3E N(neutral)
Under voltage output 230V ac, 50Hz, 2A
(AC1), for connection to the relay coil for
obtaining a free contact
r10
Num
1
Enablement of the function
-
-
r11 °C
0.5
(default)
ΔT of the auxiliary electric heaters in
heating operation
- -
r12 Min
10
(default)
Activation delay of auxiliary E-heater - -
r24
Num
1 o 3
Type of utilization of the electric heaters
-
-
9.8.2 AUXILIARY ELECTRIC HEATER OF THE PLANT IN DEFROST CYCLE
During defrost cycle (see Paragraph 7.6), by setting r21=1 (in addition to r10=1 and r24=1 or 3) the electric heater of the plant
system side will be activated if required (regulating temperature lower than the water setpoint - r11 (°C)), without waiting for the
time defined by r12.
9.8.3 ELECTRIC HEATER OF SANITARY WATER PRODUCTION
It is an additional energy resource for the sanitary water tank heating when the compressor is not able to reach the set
temperature within a reasonable time.
In order to enable this function, please enter at the page of parameters PRGPSSPRG  (insert the service password)  PRG
 PAr  PRG  CnF / rE.
Parameter
Unit
Value
Description
Terminals
Notes
H81 Num 26
Undervoltage output for
DHW auxiliary electric heater
DO7E(phase)
DO7EN(neutral)
Under voltage output 230V ac, 50Hz, 2A
(AC1), for connection to the relay coil for
obtaining a free contact
r15
Num
1
Enablement of the function
-
-
r16 Min
10
(default)
Activation delay of auxiliary
DHW electric heater
- -
r24 Num 2 or 3
Type of utilization of the
electric heaters
- -
(*) Otherwise, it is possible to use another output DO or OC.
If the production of sanitary hot water lasts for a period of time greater than r16 (minutes) and the unit stop operation because of
a fault, the electric heater will start operation and it will stop only when the unit concludes the sanitary water production. The
auxiliary electric heater of DHW can also start operation in normal heat pump mode in case of joint and substitution bands.
9.8.4 UNIQUE AUXILIARY ELECTRIC HEATER FOR BOTH PLANT SYSTEM/DHW PRODUCTION
With the following parameter setting r15=2 and by configuring the auxiliary DHW electric heater, this last could be used as a single
electric heater for sanitary production and/or plant system and/or plant system in case of defrosting cycle.
9.8.5 SELECTION MODE OF THE AUXILIARY ELECTRIC HEATERS
The activation order priority of the auxiliary electric heaters can be set for those of plant system and DHW production sides, as
particular configurations, see below:
1. r14=0 (default), the electric heaters will be activated simultaneously if were being installed;