RDZ UMHPI User Manual Download

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UMHPI

Industrial inverter air/water heat pumps with axial fans

If the DHW temperature is below the set point value (adjustable by entering the

PRG->Set->SAN

menu), the unit activates the

sanitary valve and the compressor is set at the maximum frequency starting the modulation at one degree before the set value
and it stops at one degree after the set value. Once reached the set point value, the valve switches to the stand-by mode and the
compressor works normally.
While shifting from user’s to domestic hot (sanitary) water, the operating sensor changes from “outlet water sensor” to “sanitary
tank sensor”. While shifting from the winter operating mode to the sanitary operating mode, the compressor does not switch off,
and reaches the maximum established frequency that to be controlled; on the other hand, while shifting from the summer
operating mode to the sanitary operating mode, the compressor is switched off to wait for the safety timing.
The defrosting during winter operation mode is always performed on the user side, never on the sanitary water tank.

Note:

H10 = 1

. The remote turning off the unit (remote onoff), or by the on board unit controller, or by a remote control board does

not affect the sanitary operating mode. The unit starts in sanitary mode as setting priority when it’s powered on. The on board
unit display shows the temperature measured by the sensor placed inside the sanitary water tank. Once the sanitary cycle is
completed, the display returns to show the temperature of the outlet water sensor.

If the remote ON-OFF digital input (onoff-onoff terminals) is open, with the enabling of the domestic hot water production (

H10=1

and

H20=6

), the display on-board unit shows the item "

SAN

". Once the sanitary cycle is concluded, the display returns to show the

code "

E00

" indicating that the remote ON-OFF contact is open.

- If H10

= 2

, the remote on-off function disenables the production of domestic hot water and the operations of the heat pump in

heating and cooling on plant side.

Example

of a

ctivation of this function

H10 =

H19 =



DHW temperature sensor [terminals: SAN – SAN]

H61 =

6(default)



In case of using a 3-way changeover valve with 3 contacts for power supply [terminals: NO1 – N - NC1]



In case of using a 3-way changeover valve with 2 contacts for power supply (with spring return),
[terminals: NO1 – N]

•

Closed contact NO1

means that the valve is energized and diverts the water flow to the DHW tank.

•

Open contact NO1

means that the valve is de-energized and diverts the water flow to users.

For the models UMHPI 60, this function can be activated only with the presence of the optional “GI” module.

7.12.1

MEMORY OF THE SENSOR IN HEATING MODE

In the case of commutation from water users to the domestic hot water, the temperature sensor changes from a "water outlet
temperature sensor" to a "water tank temperature sensor". For such reason, in heating mode, the last value read by the sensor
will be memorized before changing to DHW mode.
When the DHW thermoregulation is reached, the reference temperature on the plant side will take the value which is previously
memorized.
The memory function will be interrupted:

When the temperature detected by the sensor becomes lower than the memorized value;

Or after a period of time equal to

b06

seconds (default 45 seconds).

For each

UMHPI

unit (except the last unit of the cascade), you must implement a relay (not included), controlled by the output

230VAC

NO1

and

located on the terminal block, that can enable through its free contacts

COM