Mark
Part name
Description
10
Thermistor for swimming pool water
temperature
The sensor is used for the swimming pool temperature control and should be positioned inside
plate heat exchanger of the swimming pool.
11
Thermistor for second ambient
temperature
The sensor is used for the second ambient temperature control and it should be positioned
outdoors.
12
Earth
Earth connection for the 3 way valve and water pump.
13
Common line
Terminal Line common for input 1 and input 2.
14
Input 1 (Demand ON/OFF) (*)
The air to water heat pump system has been designed to allow the connection of a remote
thermostat to effectively control your home’s temperature. Depending on the room temperature,
the thermostat will turn the air to water heat pump system ON and OFF.
15
Input 2 (ECO mode) (*)
Available signal which allows to reduce the water setting temperature of circuit 1, circuit 2 or both.
16
Common line
Terminal Line common for inputs 3, 4, 5, 6, 7.
17
Input 3 (Swimming pool) (*)
Only for swimming pool installations: It is necessary to connect an external input to the air to water
heat pump to provide signal when the water pump of swimming pool is ON.
18
Input 4 (Solar) (*)
Available input for Solar combination with Domestic Hot Water Tank.
19
Input 5 (Smart function) (*)
For the connection of an external tariff switch device to switch OFF the heat pump during peak
electricity demand period. Depending on the setting, the heat pump or DHWT will be blocked
when signal is open/closed.
20
Input 6 (DHW boost) (*)
Available input for an instantaneous heating of the domestic hot water of the tank.
21
Input 7 (Power meter)
The measuring of the real power consumption can be done connecting an external power meter.
The number of pulses of the power meter is a variable which must be set. By this, every pulse
input is added into corresponding operation mode (Heating, Cooling, DHW Operation). Two
possible options:
- One power meter for all installation (IU+OU).
- Two separated power meters (one for IU and one for OU).
22
Aquastat security for circuit 1 (WP1)
Terminals intended for the connection of the Aquastat security accessory (ATW-AQT-01) for
controlling water temperature of the circuit 1.
23
24(C) Mixing valve close
When a mixing system is required for a second temperature control, these outputs are necessary
to control the mixing valve.
25(O) Mixing valve open
26(N) N Common
27(L) Water Pump 2 (WP2)
When there is a second temperature application, a secondary pump is the circulating pump for the
secondary heating circuit.
28
Auxiliary power
Power supply for ATW-RTU and central device
29
30(N)
Electrical Heater DHW Output
If DHW tank contains an electric heater, the air to water heat pump can activate it if the heat pump
cannot achieve the required DHW temperature by itself.
31(L)
32(C) Common line
Common terminal for the 3-way valve for DHW tank.
33(L) 3-way valve for DHW tank
The air to water heat pump can be used to heat DHW. This output will be on when DHW is
activated.
34(N) N common
Neutral terminal common for 3-way valve of DHW tank and outputs 1 and 2.
35(L) Output 1 (3-way valve for swimming
pool) (*)
The air to water heat pump can be use to heat swimming pool. This output will be ON when
swimming pool is activated.
36(L) Output 2 (Water pump 3 (WP3)) (*)
When there is a hydraulic separator or buffer tank, additional water pump (WP3) is needed.
37
Output 3 (Auxiliary boiler or electric
heater) (*)
The boiler can be used to alternate with the heat pump when the heat pump cannot achieve the
required temperature by itself.
A water electric heater (as accessory) can be used to provide the additional heating required on
the coldest days of the year.
38
39
Output 4 (Solar) (*)
Output for solar combination with Domestic Hot Water Tank.
40
?
N O T E
(*): Inputs and outputs explained in the table are the factory-set options. By means of the unit controller, some other inputs and outputs functions can
be configured and used. Please, refer to the Service Manual for detailed information.
ELECTRICAL AND CONTROL SETTINGS
PMML0506 rev.2 - 01/2021
17
EN