System 4: Single Boiler With Rc35, One Heating Zone, & Solar Thermal Dhw - Buderus Logamax plus GB162 Applications Manual

GB162 Applications Manual
3.4 System 4: Single boiler with RC35, one heating zone, & solar thermal DHW
Summary:
Ideal setup for large open floor plans, e.g. restaurants,
churches, retail, shop floors, etc. plus a significant DHW
demand daily. Single boiler system supplying one unmixed
heating zone combined with solar thermal DHW with boiler
backup. This is a proven system that is simple to install, almost
maintenance free, and fully automated.
• Outdoor reset with room feedback
• RC35 room sensor and user interface installed in a
reference room for room feedback
• Zone pump is controlled by the boiler
• Separate day and night temperature program with multiple
setpoints for the heating zone and DHW separately
• DHW loading with or without priority
• Maximum efficiency from outdoor reset based on heat loss
of the structure and maximum comfort from room feedback
• Solar thermal system loads the DHW tank when solar
energy can be harvested
• Integration of solar thermal with the boiler reduces boiler
starts and boiler run time and saves fuel
In detail:
The RC35 computes a quantified heat demand for the structure
based on information from the outdoor sensor, its internal room
sensor, and the heating curve.
Applications include a high, medium and low temperature zone
(e.g. radiant floor, panel radiators, baseboard or hydro-air).
Day and night temperatures can be set based on the unique
requirements of the zone and when occupants will be present
and absent.
The WM10 module controls the zone pump in constant
circulation which prevents temperature swings and provides
maximum comfort.
The modulating boiler strives to run at low fire for the longest
time possible where efficiency is at its highest.
RC35 user interface with integrated room sensor and full text
display for easy programming and operation.
Display of outdoor temperature curve for yesterday and today.
Holiday function allows reduced temperatures during absence
and bringing the space back to temperature in time when
returning home.
Solar thermal DHW functionality integrated in controls delays
or prevents reheating of the tank using fossil fuels when solar
activity has been detected. The proven algorithm for solar
thermal integration in the boiler control system can reduce DHW
burner starts for DHW generation by 25% and fossil
Logamax plus GB162 applications manual | 03.2013
fuel usage even further compared to a 3rd party solar thermal
system. DHW reheating by the boiler is done according to a
customized timer program. DHW priority over space heating
can be enabled or disabled. DHW single charge button to
reload the tank during night mode.
The RC35 displays solar thermal gain for comparison with
previous days.
The low loss header decouples the boiler loop from the system.
DHW recirculation pump functionality is built in with separate
timer program.
Required components:
• GB162 boiler
• RC35 controller
• WM10 LLH module
• SM10 Solar module
• PH zone circulator
• PS DHW tank loading circulator.
• Buderus solar thermal system with collectors, mounting
rack, line set, and pump station
• Solar DHW tank
Additional instructions:
Install the zone supply temperature sensor FK after the
respective pump in order to be able to detect pump failure.
ECM pumps (low energy or constant pressure pumps) are
recommended for constant flow rate and additional energy
savings.
Control modes
The following control modes are available with the RC35:
• Outdoor reset (factory default):
The system water temperature is calculated in response
to the outdoor temperature. This temperature is then
delivered to the zones by a constantly operating heating
zone pump. The pump will only shut-down in warm weather
shut down, night setback (shut-down mode only) or DHW
mode (domestic hot water priority only). Install the RC35
unit in the boiler, or in the room with maximum room
influence set to 0 (factory setting).
• Outdoor reset with room influence:
The RC35 must be installed in a reference room in order
to record the room temperature accurately. The higher the
room influence parameter set the greater its influence on
the heating curve. If maximum room influence is set to 0
(factory setting), room feedback is disabled.
• Room reset:
With outdoor reset disabled and the RC35 installed in a
reference room the system water temperature is influenced
only by the conditions in the room. Applications include
super insulated structures, or rooms with significant solar
gain, auxiliary heat (wood stove), or similar.
Technical specifi cations are subject to change without prior notice
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