Appendix
44 Installation and maintenance instructions SUSTAIN ..c 0020200954_00
K Technical data
Technical data – Heating
SUSTAIN 25c -A (H-
GB)
SUSTAIN 30c -A (H-
GB)
SUSTAIN 35c -A (H-
GB)
Max. flow temperature adjustment
range (default setting: 75 °C)
10 … 80 ℃ 10 … 80 ℃ 10 … 80 ℃
Maximum permissible pressure
0.3 MPa
(3.0 bar)
0.3 MPa
(3.0 bar)
0.3 MPa
(3.0 bar)
Nominal water flow (ΔT = 20 K)
788 l/h 788 l/h 788 l/h
Nominal water flow (ΔT = 30 K)
525 l/h 525 l/h 525 l/h
Approximate value for the
condensate volume (pH value
between 3.5 and 4.0) at 50/30 °C
1.84 l/h 1.84 l/h 1.84 l/h
ΔP heating at nominal flow (ΔT =
20 K)
0.025 MPa
(0.250 bar)
0.025 MPa
(0.250 bar)
0.018 MPa
(0.180 bar)
Technical data – G20 power/loading G20
SUSTAIN 25c -A (H-
GB)
SUSTAIN 30c -A (H-
GB)
SUSTAIN 35c -A (H-
GB)
Maximum heat output
18 kW 25 kW 25 kW
Effective output range (P)
at 40/30 °C
5.4 … 19.5 kW 6.5 … 19.5 kW 7.6 … 19.5 kW
Effective output range (P)
at 50/30 °C
5.3 … 19.1 kW 6.3 … 19.1 kW 7.5 … 19.1 kW
Effective output range (P)
at 80/60 °C
5.1 … 18.3 kW 6.1 … 18.3 kW 7.2 … 18.3 kW
Domestic hot water heat
output (P)
5.0 … 25.2 kW 6.0 … 30.0 kW 7.1 … 35.0 kW
Maximum heat input –
heating (Q max.)
18.4 kW 18.4 kW 18.4 kW
Minimum heat input – heat-
ing (Q min.)
5.1 kW 6.1 kW 7.2 kW
Maximum heat input – hot
water (Q max.)
25.7 kW 30.6 kW 35.7 kW
Minimum heat input – hot
water (Q min.)
5.1 kW 6.1 kW 7.2 kW
Technical data – Domestic hot water
SUSTAIN 25c -A (H-
GB)
SUSTAIN 30c -A (H-
GB)
SUSTAIN 35c -A (H-
GB)
Specific flow rate (D) (ΔT = 30 K)
in accordance with EN 13203
12.1 l/min 14.2 l/min 16.5 l/min
Continuous flow rate (ΔT = 35 K)
622 l/h 730 l/h 849 l/h
Specific flow rate (ΔT = 35 K)
10.4 l/min 12.2 l/min 14.1 l/min
Minimum permissible pressure
0.3 MPa
(3.0 bar)
0.3 MPa
(3.0 bar)
0.3 MPa
(3.0 bar)
Maximum permissible pressure
1 MPa
(10 bar)
1 MPa
(10 bar)
1 MPa
(10 bar)
Recommended pressure
0.2 MPa
(2.0 bar)
0.2 MPa
(2.0 bar)
0.2 MPa
(2.0 bar)
Temperature range
35 … 60 ℃ 35 … 60 ℃ 35 … 60 ℃
Throughflow volume limiter
8.0 l/min 10.0 l/min 12.0 l/min