Operating Principle - Fujitsu WATERSTAGE WOYG112LHT Maintenance Document

Air to Water Heat Pump (Split integrated DHW type)
6
1 .5

Operating principle

The heat pump transmits the energy contained in the
surrounding air into the dwelling to be heated.
The heat pump consists of four main elements, in which
a refrigerant fluid (R410A) circulates.
- In the evaporator (ref. 13,
The energy is taken from the surrounding air and is
transmitted to the refrigerant. Because it has a low
boiling point, it changes from the liquid state to the
vapour state, even in cold weather (down to -25 °C
outdoor temperature).
- In the compressor (ref. 10,
The vaporised refrigerant brought to high pressure
and takes on more calories.
- In the condenser
The energy in the refrigerant is transmitted to the
heating circuit. The refrigerant returns to liquid state.
- In the expansion valve (ref. 9,
The liquefied refrigerant is brought back to low pressure
and returns to its initial temperature and pressure.
The heat pump is equipped with a controller, which
controls the room temperature based on the outdoor
temperature measurement and governed by the
temperature control. The room thermostat (option)
provides a corrective action for the temperature control.
The hydraulic unit can be optionally fitted with an
electrical back-up system or boiler connection which
starts up in order to provide addtional heating during the
coldest periods.
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7
13
15
18
2
12
3
1
10
8
9
21
23
14
4
5
22
9
11
17
16
9
figure 7 - Hydraulic unit components
figure 6, page
figure 6, page
(ref. 15, figure
figure 6, page
• Regulation functions
- The heating circuit's initial temperature is controlled by
the temperature control.
- The power of the outdoor unit is modulated according
to flow heating temperature via the "inverter"
compressor.
9) :
- Control of the electrical back-up heating (option).
- The daily timer program enables you to define
the periods for comfortable or reduced ambient
temperature.
- Summer/winter mode switchover is automatic.
9) :
- Control of the supplementary boiler* (option).
- The room thermostat (option)*: provides a corrective
action for the temperature control.
7) :
- Control of a second heating circuit*.
- Domestic hot water: Heating time programme, control
of the operation of the DHW circulation pump.
9) :
- Managing the cooling*.
- Control of swimming pool heating*.
* If the heat pump is equipped with optional equipment and the
associated kits.
• Protection functions
- Anti-legionella cycle for domestic hot water.
- Anti-corrosion protection with titanium anode (ACI).
- Frost protection: Frost protection cuts in if the low-
temperature point of the heating circuit falls below 5 °C
(provided that the heat pump's electrical power supply
is not interrupted).
Legend :
1 - Electric box.
2 - Regulator / User interface.
3 - Start/stop switch.
4 - Hydraulic pumping unit.
5 - Distribution valve.
6 - "Gas" refrigerant connection.
7 - "Liquid" refrigerant connection.
8 - Condensation sensor.
9 - Drain valve.
10 - Safety valve.
11 - Safety thermostat.
12 - Manometer.
13 - Manual drainer.
14 - Expansion vessel.
15 - Condenser.
16 - Electrical back-ups DHW.
17 - ACI.
18 - ACI card.
Sensors :
21 - Water flow sensor.
22 - DHW sensor.
23 - Water return sensor.
Installation and operating manual "1768 - EN"