Programming Unit And Direct Heating Circuit Without Mixer - Buderus Logamax plus GB162 Technical Manual

6.4.4 System example for the Logamax plus GB162-50/65/80/100 with DHW heating via a 3-way diverter
valve, RC35 programming unit and direct heating circuit without mixer
PZ
KR
EK
Fig. 77 Circuit diagram for the system example (index of abbreviations
1)
Hydraulic balancing at the thermostatic valves
recommended
2)
External pump Wilo Stratos 25/1-8 available as an
accessory, alternative options Grundfos Magna 25-60 or
Magna 25-100
3) 3
DN32, K = 18 m /h
VS
The circuit diagram is only a schematic
illustration.
Information regarding all system examples
page 52 ff.
Brief description
• DHW heating with priority via an external 3-way
diverter valve, DN32.
• An individual time channel is available for DHW.
• External pump for installation below the boiler:
– Grundfos Magna 25-60 for GB162-50/65
– Wilo Stratos 25/1-8 or Grundfos Magna 25-100 for
GB162-50/65/80/100
• Available residual head (observe pump curve
page 61 ff.):
– at 2800 l/h = 180 mbar
(GB162-50/65 with Grundfos Magna 25-60)
– at 4000 l/h = 150 mbar to 200 mbar
(GB162-65/80/100 with Wilo Stratos 25/1-8 or
Grundfos Magna 25-100)
• Pressure drop for the 3-way diverter valve:
– at 2800 l/h = 30 mbar
– at 4000 l/h = 50 mbar
6 720 645 821 (2010/09) – Logamax plus GB162
FA
2x0,6 2
VS
VK
3)
G-SU
FW
RS
RC35
FS
BUS
BC10
2)
SV
MAG
RK
SMF
page 52)
• ΔT of the appliances at 4000 l/h:
– 50 kW = 11 K
– 65 kW = 14 K
– 80 kW = 18 K
– 100 kW = 21 K
• ΔT of the appliances at 2800 l/h:
– 50 kW = 15 K
– 65 kW = 20 K
Special design information
• The DHW temperature sensor FW is connected at the
terminal strip of the gas condensing boiler.
• Buderus cylinders from 400 l can be used. Observe
the pressure drop of the indirect coils inside the
cylinder.
• For cylinders smaller than 400 l, check the constant
cylinder output at a reduced flow rate. The constant
cylinder output at a reduced heating water flow rate
should be at least 35 kW. Where this cannot be
guaranteed, the boiler may frequently cycle.
System examples 6
1)
THV HK
6 720 642 463-61.1il
79