To Check The Water Volume And Flow Rate; Changing The Pre-Pressure Of The Expansion Vessel - Daikin Altherma H Hybrid EJHA04AAV3 Installer's Reference Manual

9.3.4 To check the water volume and flow rate

9.3.5 Changing the pre-pressure of the expansion vessel

EJHA04AAV3 + EHY2KOMB28+32AA
Daikin Altherma H Hybrid
4P531180-1D – 2025.03
Minimum water volume
The installation needs to be made in such a way that a minimum water volume of
20 litres is always available in the space heating loop of the unit, even when the
available volume towards the unit is reduced because of closure of valves (heat
emitters, thermostatic valves, etc.) in the space heating circuit. The internal water
volume of the outdoor unit is NOT considered for this minimum water volume.
INFORMATION
In critical processes, or in rooms with a high heat load, extra water might be
required.
b
a
a Outdoor unit
b Heat exchanger
c Pump
d Boiler
e Shut‑off valve (field supply)
f Collector
g Bypass valve (field supply)
RAD1...3 Radiator (field supply)
Minimum flow rate
A minimum flow rate must be guaranteed so that the outdoor unit does not go in
high pressure error (A5). For guidelines on flow rates, see the tables in
"9.3.1 Water piping lengths and height difference
Minimum required flow rate
(a)
7 l/min
(a) Below this value, no stable operation can be guaranteed.
NOTICE
When circulation in each or certain space heating loops is controlled by remotely
controlled valves, it is important that the minimum flow rate is guaranteed, even if all
valves are closed. In case the minimum flow rate cannot be reached, the heat pump
generates a high pressure error (A5).
NOTICE
ONLY a licensed installer may adjust the pre-pressure of the expansion vessel.
The expansion vessel is available with the B-pack (see
4
boiler" [ 41]) or as a third-party vessel. For more information on how to change
the pre-pressure, see the manual of the expansion vessel.
Changing the pre-pressure of the expansion vessel should be done by releasing or
increasing nitrogen pressure through the Schrader valve of the expansion vessel.
d e f
c
RAD1 RAD2 RAD3
e
9 Preparation
|
95°C
g
4
" [ 67].
"Possible options for the gas
Installer reference guide
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