6 - APPLICATION DATA
6.5 - Water loop volume
6.5.1 - Minimum water loop volume
The heat pump is used in a domestic hot water application and
must heat an intermediate loop that supplies domestic hot water
via a heat exchanger. The primary loop is charged with softened
water. Regular checks must be carried out on the water system
to detect possible scale formation. The heat pump in this type
of application must never supply domestic hot water directly.
The minimum water loop volume, in litres, is given by the following
formula:
Volume (l) = CAP (kW) x N, where CAP is the nominal heating
capacity at nominal operating conditions.
Heating or domestic hot water application
N
TD 080-150
5,0 l
TD 200-300
3,0 l
This volume is required to obtain temperature stability and
precision.
To achieve this volume, it may be necessary to add a storage
tank to the circuit. This tank should be equipped with baffles to
allow mixing of the fluid (water or brine). Please refer to the
examples below.
Bad
Good
Bad
Good
6.5.2 -
Expansion tank volume
Units do not incorporate an expansion tank. This must be
included in the water loop.
The table below gives the buffer tank volume that must be
provided, based on the water loop volume, the fluid used and its
concentration.
Expansion tank volume required
% of water loop volume
(1)
Pure water
3,0
10% ethylene glycol
3,0
20% ethylene glycol
3,5
30% ethylene glycol
3,8
40% ethylene glycol
4,2
(1) Calculation based on a charge temperature of 10°C.
6.6 - Plate heat exchanger pressure drop
curves
For pure water at 20°C
Pressure drop, kPa
Water flow rate, l/s
0
5
10
15
20
25
30
0
1
2
3
4
5
1
2
3
B
TD 080
C
TD 100
D
TD 120
0
10
20
30
40
50
0
2
4
6
8
10
1
2
3
Water flow rate, l/s
Pressure drop, kPa
B
TD 150
C
TD 200
D
TD 300
AQUACIAT
CALÉO™
TD
EN-20
