9 Maintenance and service
Installation manual
40
EWSAH/X06UDA9W
Daikin Altherma 3 WS
4P675760-1 – 2021.10
9
Maintenance and service
NOTICE
Maintenance MUST be done by an authorised installer or
service agent.
We recommend performing maintenance at least once a
year. However, applicable legislation might require shorter
maintenance intervals.
NOTICE
Applicable legislation on
fluorinated greenhouse gases
requires that the refrigerant charge of the unit is indicated
both in weight and CO
2
equivalent.
Formula to calculate the quantity in CO
2
equivalent
tonnes:
GWP value of the refrigerant × total refrigerant
charge [in kg] / 1000
9.1
Maintenance safety precautions
DANGER: RISK OF ELECTROCUTION
DANGER: RISK OF BURNING/SCALDING
NOTICE: Risk of electrostatic discharge
Before performing any maintenance or service work, touch
a metal part of the unit in order to eliminate static electricity
and to protect the PCB.
9.2
Yearly maintenance
9.2.1
Yearly maintenance: overview
▪ Central water loop circuit leakage
▪ Temperature and pressure relief valve
▪ Chemical disinfection
▪ Descaling
▪ Drain hose
▪ Fluid pressure of space heating and central water loop circuit
▪ Pressure relief valves (1 at central water loop side, 1 at space
heating side)
▪ Pressure relief valve of the domestic hot water tank
▪ Switch box
▪ Water filters
9.2.2
Yearly maintenance: instructions
Central water loop leakage
Open the front panels and carefully check if a leakage in the piping
from and to the central water loop is noticeable. See
Temperature and pressure relief valve
Check for correct operation of the temperature and pressure relief
valve. Manually operate the temperature and pressure relief valve to
ensure free water flow through discharge pipe. Turn knob left.
Pressure reducing valve
Depending on local water conditions, annual inspection of the
integral line strainer, pressure reducing valve cartridge and seating
may be necessary.
c
a
b
a
Cartridge
b
Strainer
c
Calibration screw
1
Unscrew the plastic cover of the pressure reducing valve.
2
Extract the cartridge with the aid of long nosed pliers to grip the
head of the set screw.
3
Remove the strainer element.
4
Clean the strainer element and cartridge under clean running
water.
5
Replace if the strainer or cartridge are damaged.
6
Refit the strainer, cartridge and cover.
7
If the cartridge has been replaced, calibrate the pressure
reducing valve:
▪ Close the downstream isolating valve (field supply).
▪ Install an Allen key on the calibration screw in the centre of
the plastic cover. Rotate it clockwise to increase the outlet
pressure and anticlockwise to reduce it.
Chemical disinfection
If the applicable legislation requires a chemical disinfection in
specific situations, involving the domestic hot water tank, please be
aware that the domestic hot water tank is a stainless steel cylinder
containing an aluminium anode. We recommend to use a non-
chloride based disinfectant approved for use with water intended for
human consumption.
NOTICE
When using means for descaling or chemical disinfection,
make sure water quality still complies with EU directive
2020/2184.
Descaling
Depending on water quality and set temperature, scale can deposit
on the heat exchanger inside the domestic hot water tank and can
restrict heat transfer. For this reason, descaling of the heat
exchanger may be required at certain intervals.
Drain hose
Check the condition and routing of the drain hose. Water must drain
appropriately from the hose. See
"3.3.2 To connect the drain hose to
Fluid pressure
Check whether the fluid pressure is above 1 bar. If it is lower, add
fluid.
