Preparing Water Piping; Water Circuit Requirements - Daikin CHYHBH05AA Installer's Reference Manual

6 Preparation
6.4

Preparing water piping

6.4.1

Water circuit requirements

INFORMATION
Also read the precautions and requirements in the
"General safety precautions" chapter.
NOTICE
In case of plastic pipes, make sure they are fully oxygen
diffusion tight according to DIN 4726. The diffusion of
oxygen into the piping can lead to excessive corrosion.
▪ Connecting piping – Legislation. Make all piping connections in
accordance with the applicable legislation and the instructions in
the "Installation" chapter, respecting the water inlet and outlet.
▪ Connecting piping – Force. Do NOT use excessive force when
connecting the piping. Deformation of the piping can cause
malfunctioning of the unit.
▪ Connecting piping – Tools. Only use appropriate tooling to
handle brass, which is a soft material. If NOT, pipes will get
damaged.
▪ Connecting piping – Air, moisture, dust. If air, moisture or dust
gets into the circuit, problems may occur. To prevent this:
▪ Only use clean pipes
▪ Hold the pipe end downwards when removing burrs.
▪ Cover the pipe end when inserting it through a wall, to prevent
dust and/or particles entering the pipe.
▪ Use a decent thread sealant to seal connections.
▪ Closed circuit. Use the indoor unit ONLY in a closed water
system. Using the system in an open water system will lead to
excessive corrosion.
▪ Piping length. It is recommended to avoid long runs of piping
between the domestic hot water tank and the hot water end point
(shower, bath,...) and to avoid dead ends.
▪ Piping diameter. Select the water piping diameter in relation to
the required water flow and the available external static pressure
of the pump. See "15 Technical data" on page 84
static pressure curves of the indoor unit.
▪ Field supply components – Water. Only use materials that are
compatible with water used in the system and with the materials
used in the indoor unit.
▪ Field supply components – Water pressure and temperature.
Check that all components in the field piping can withstand the
water pressure and water temperature.
▪ Water temperature – Heat pump convectors. In case heat
pump convectors are connected, the temperature of the water in
the convectors should NOT exceed 65°C. If necessary, install a
thermostatic controlled valve.
▪ Water temperature – Underfloor heating loops. In case
underfloor heating loops are connected, install a mixing station to
prevent water that is too hot from entering the underfloor heating
circuit.
▪ Water temperature. All installed piping and piping accessories
(valve, connections,...) MUST
temperatures:
INFORMATION
The following illustration is an example and might NOT
match your system layout.
Installer reference guide
18
for the external
withstand the following
65°C
a b d e g
c f g
l
a Outdoor unit
b Indoor unit
c Heat exchanger
d Boiler
e Bypass valve
f Pump
g Shut-off valve (field supply)
h Motorised 3-way valve (in option kit)
i Collector
j Domestic hot water tank (optional)
k Heat exchanger coil
l Direct expansion unit
FCU1...3 Fan coil unit (optional)
RAD1...3 Radiator (field supply)
▪ Drainage – Low points. Provide drain taps at all low points of the
system in order to allow complete drainage of the water circuit.
▪ Air vents. Provide air vents at all high points of the system, which
must also be easily accessible for servicing. An automatic air
purge is provided in the indoor unit. Check that the air purge is
NOT tightened too much, so that automatic release of air in the
water circuit is possible.
▪ Zn-coated parts. Never use Zn-coated parts in the water circuit.
Because the unit's internal water circuit uses copper piping,
excessive corrosion may occur.
▪ Non-brass metallic piping. When using non-brass metallic
piping, insulate the brass and non-brass properly so that they do
NOT make contact with each other. This to prevent galvanic
corrosion.
▪ Valve – Separating circuits. When using a 3-way valve in the
water circuit make sure that the domestic hot water circuit and the
floor heating circuit is fully separated.
▪ Valve – Change‑over time. When using a 2-way valve or a 3-way
valve in the water circuit, the maximum change-over time of the
valve must be 60 seconds.
▪ Filter. It is strongly recommended to install an additional filter on
the heating water circuit. Especially to remove metallic particles
from foul heating piping, it is recommended to use a magnetic or
cyclone filter, which can remove small particles. Small particles
may damage the unit and will NOT be removed by the standard
filter of the heat pump system.
▪ Dirt separator – Old heating installations. In case of old heating
installations, it is recommended to use a dirt separator. Dirt or
sediment from the heating installation can damage the unit and
reduce its lifetime. The domestic hot water circuit can also be
protected by a filter to prevent failure during domestic hot water
operation.
▪ Domestic hot water tank – Capacity. To avoid stagnation of
water, it is important that the storage capacity of the domestic hot
water tank meets the daily consumption of domestic hot water.
Daikin hybrid for multi heat pump – heat pump module
95°C
h
FCU1
FCU2
i
FCU3
M
RAD1 RAD2 RAD3
89°C
j
k
CHYHBH05+08AA + EHYKOMB33A
4P471761-1A – 2017.10