Daikin Altherma 3 H MT W, Installer'S Reference Manual

Page: 250 / 296

14 | Troubleshooting
Installer reference guide
250
EPRA08~W1 + ETBH/9W
Daikin Altherma 3 H MT W
4P634885-1 – 2021.03
14.3.6 Symptom: The pump is making noise (cavitation)
Possible causes Corrective action
There is air in the system Purge air manually (see "To perform a
manual air purge" [
4
231]) or use the
automatic air purge function (see "To
perform an automatic air
purge"
[
4
232]).
The water pressure at the pump inlet is
too low Check and make sure that:
▪ The water pressure is >1 bar.
▪ The water pressure sensor is not
broken.
▪ The expansion vessel is NOT broken.
▪ The valve (if equipped) of the water
circuit towards the expansion vessel is
open.
▪ The pre-pressure setting of the
expansion vessel is correct (see
"8.1.4 Changing the pre-pressure of
the expansion vessel"
[
4
88]).
14.3.7 Symptom: The pressure relief valve opens
Possible causes Corrective action
The expansion vessel is broken Replace the expansion vessel.
The valve (if equipped) of the water
circuit towards the expansion vessel is
closed. Open the valve.
The water volume in the installation is
too high Make sure that the water volume in the
installation is below the maximum
allowed value (see
"8.1.3 To check the
water volume and flow rate" [
4
86] and
"8.1.4 Changing the pre-pressure of the
expansion vessel"
[
4
88]).
The water circuit head is too high The water circuit head is the difference
in height between the indoor unit and
the highest point of the water circuit. If
the indoor unit is located at the highest
point of the installation, the installation
height is considered 0 m. The maximum
water circuit head is 10 m.
Check the installation requirements.