System 5: Multi Boiler System With Staging Control And Outdoor Reset - Buderus Logamax plus GB162 Applications Manual

GB162 Applications Manual

3.5 System 5: Multi boiler system with staging control and outdoor reset

The GB162 was designed from the beginning as a cascadable
appliance. With its modulation range of 20-100% (1:5)*
cascading appliances will achieve the following turndown ratios:
# of GB162's in cascade
2
3
4
5
10
16
Table 4 Turndown Ratios
Compared to large mass boilers this allows matching
applications with greatly varying loads while running at the most
efficient low modulation.
Summary:
Multi-boiler system with staging control and outdoor reset.
• MCM10 Staging control for 2 to 16 boilers
• Outdoor reset
• Dry contact heat demand
• Optional 0-10V input (see Appendix 1)
Buderus offers convenient racking systems and cascade
system piping with low loss headers for quick and easy
installation.
In detail:
The cascade controller fires, runs, and modulates the boilers
based on heat demand, plus rotates the boilers to achieve
equal run time.
The cascade controller strives to run boilers at low fire for the
longest time possible where efficiency is at their highest.
The low loss header decouples the boiler loop from the system
loop with the same boiler flow rate independently of the number
of zones calling.
* GB162/100
Logamax plus GB162 applications manual | 03.2013
Turndown Ratio
1:10
1:15
1:20
1:25
1:50
1:80
Required components:
• Up to sixteen GB162 boilers
• AM10 Outdoor Reset Module (for outdoor reset control)
• MCM10 Multi Cascade Module (one for every 4 boilers)
• PH zone circulators
• TL2, TL3, TL4
• Optional inline cascade racks including LLH and manifolds:
TL2, TL3, TL4
• Optional back to back cascade racks including LLH and
manifolds: TR2, TR4
Additional instructions:
ECM pumps (low energy or constant pressure pumps)
recommended for zoning to dial in desired flow rate and delta T,
and reduce electricity consumption.
Technical specifi cations are subject to change without prior notice
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