17
English
Piping instal
lation
Outdoor water piping insulation
The complete water circuit, inclusive all the piping, must be insulated
to prevent condensation during cooling operation and reduction of
the heating and cooling capacity as well as prevention of freezing
of the outside water piping during winter time. The thickness of the
sealing materials must be at least 9 mm with ƛ=0.035 W/mK in order
to prevent freezing on the outside water piping.
If the temperature is higher than 30°C and the humidity is higher
than RH 80%, then the thickness of the sealing materials should be
at least 20 mm in order to avoid condensation on the surface of the
sealing.
For piping in free air, it is recommended to use the insulation
thickness as shown in the below table as a minimum
(with ƛ=0.035 W/mK).
Piping length (m)
Minimum insulation thickness (mm)
< 20
19
20 ~ 30
32
30 ~ 40
40
40 ~ 50
50
NOTE
• This recommendation ensures good operation of the unit,
however, local regulations may differ and shall be followed.
Minimum active water volume
The minimum active water volume of the system is the amount of
water which is always pumped around, even when all valves in the
system are closed. The use of a buffer tank can increase the active
volume and therefore the operation time between compressor start
and stop.
Ideally, systems should be designed for around 12 to 15 minutes of
operation, in order to meet with our declared efficiencies.
This time frame is based on a maximum of 4 On/Off cycles per hour.
The required minimum active water volume can be calculated via the
below stated formula:
V
min
=
t
min
X Φ
min
C
water
X ΔT
V
min
: Minimum active volume
[dm3]
t
min
: Minimum allowed operation time is 12 min or 720 sec per cycle [s, sec]
Φ
min
: Minimum compressor output
[kW = kJ/s]
C
water
: Specific heat of water (4,2)
[kJ/kg*K]
ΔT
: Temperature increase (5-10 K)
[K]
Summary of Contents for AE CXYD Series
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