Buderus Logamax plus GB162 Technical Manual page 54

6 System examples
Pos. General design information on hydraulics and control
Observe all building regulations applicable to installation rooms (DVGW-TRGI 2008 [Germany]). Make the gas
connection in line with the technical rules applicable to gas installations. Take any DHW booster heating functions
A
of the appliances into account when sizing the gas flow limiter. The gas connection must only be made by
authorised gas fitters. In addition, the installation of a gas filter in the gas line is also recommended.
Operation in occupied rooms is possible with a balanced flue system or, under certain conditions, with the
B
concentric open flue system GA-X (DVGW-TRGI 2008 [Germany]).
When draining condensate, observe all relevant local waste water ordinances. Frequently installations follow the
C
ATV-DVWK A251 [Germany].
Only operate the Logamax plus GB162 gas condensing boiler in sealed unvented heating systems. Convert open
D
vented systems in accordance with DIN-EN 12828.
"
A "short-circuit line between the DHW cylinder flow and the DHW cylinder return is required if no separate DHW
S
cylinder is connected to the Logamax plus GB162-15/25/35 gas condensing boilers.
To prevent corrosion damage, never use zinc-plated/galvanised connection lines or fittings in the DHW outlet.
Implement the installation in accordance with DIN 1988 and DIN 4753 (as well as DIN-EN 1717) [or local
regulations]. Observe any orders concerning potable water. A copper-soldered stainless steel plate heat
F
exchanger is part of the Logamax plus GB162-25 T40S.
When connecting the Logamax plus GB162-25 T40S to plastic cold water or DHW lines, observe the methods of
connection with other materials recommended by the manufacturer of the plastic pipe.
G A stainless steel stratification cylinder with 40 l capacity is integrated into the Logamax plus GB162-25 T40S.
An extensive range of accessories is available for all Logamax plus GB162 gas condensing boilers. There are
1 suitable pipe assemblies to connect the Logamax plus GB162 gas condensing boilers with the Logalux
S135 RW, S160 RW, Logalux S120 W as well as the Logalux SU160 W to SU300 W DHW cylinders.
Observe the pump curve for checking the residual head. The Logamax plus GB162-45/50/65/80/100 appliances
are supplied without internal heating circuit pumps. A UPM 15-70 2W (GB162-45) pump, or the pump connection
assembly (GB162-50/65/80/100) with UPER 25-80, is available for delivery from the factory. These pumps can
be operated in output-dependent mode and, up to 45 kW also in Δp = constant mode. Furthermore, standard
2
differential pressure-dependent pumps can be used outside the appliance. The maximum possible amount of water
via the appliance is as follows:
45 kW = 2500 l/h; 50/65/80/100 kW = 5700 l/h
This must be safeguarded via a line balancing valve.
3 The Logamax plus GB162 can be operated without a minimum flow rate, making an overflow valve superfluous.
For room temperature-dependent or weather-compensated control with room temperature hook-up, install a room
temperature sensor in the reference room of the residential unit. The room temperature sensor is integrated in the
4
RC35 and RC25 programming units. Open all thermostatically controlled radiator valves fully in the reference
room.
A low water indicator is not required when installing the Logamax plus GB162 gas condensing boiler as an attic
5 heating centre. The function of a thermostatically controlled low water indicator is safeguarded with a minimum
pressure switch inside the appliance and is verified by type testing.
A dirt trap is not required if a new system is thoroughly flushed prior to commissioning, and oxygen corrosion
6 (loose particles) can be prevented. Older systems must always be flushed; the installation of a dirt trap is also
highly recommended.
A boiler drain & fill valve (FE) is included in the heating circuit connection set (accessory). In addition we
7
recommend providing a drain facility at the lowest point of the system.
Table 22 Information regarding the sample circuit diagrams (
the Logamax plus GB162
54
fig. 46 and fig. 47, page 53) for all systems that include
6 720 645 821 (2010/09) – Logamax plus GB162
Further
information
Page 30
Page 109 f.
Page 109 f.
Page 111 f.
Page 85
Page 30
Page 56 f.
Page 71
Page 87 f.
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Pages 87 ff.
Page 60 f.
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Page 37
Page 9 ff.
Page 56
Pages 87 ff.