User Manual

35
AUTOMATIC CONTROL
1 HEATING CONTROL BT Reason for energy savings
1.8 Heat generator control (outdoor unit)
The goal consists generally in maximizing the
heat generator efficiency
0
On/Off-control of heat generator The delivered heat from the heat generator can
only roughly be adjusted to the needs of the
consumers. The adjustment mainly happens by
changing the switching frequency. This results in
reduced efficiency of the heat generator.
1
Multi-stage control of heat generator capacity
depending on the load or demand (e.g. on/off of
several compressors)
The delivered heat can be better adjusted to the
needs of the consumers by swichting of several
stages. By that the efficiency of the heat
generator is improved.
2
Variable control of heat generator capacity
depending on the load or demand (e.g. hot gas
bypass, inverter frequency control)
By variably controlling the heat generator based
on load or demand the heat can be always be
produced optimally and the efficiency of the heat
generator will be maximized.
1.9 Sequencing of different heat generators
This control function only applies to a system
with a set of different heat generator sizes or
types including Renewable Energy Sources
0
Priorities only based on running time Based on that the running times can be
distributed amongst the different heat generators
as desired.
1
Control according to fixed priority list:
e.g. heat pump prior to hot water boiler
With this, more efficient heat generators can be
run with priority. This has a positive effect on the
annual performance factor (APF).
2
Control according to dynamic priority list (based
on current efficiency and capacity of generators)
e.g. solar, geothermal heat, cogeneration plant,
fossil fuels)
By considering actual efficiency and operating
situations it is possible to run the most
appropriate combination. This further increases
the annual performance factor (APF).
3
Control according to dynamic priority list (based
on predicted and current load, efficiency and
capacity of generators)
By considering actual efficiency and operating
situations and by predicting the expected future
operating situation with the corresponding
efficiency factors the various heat generators
can by operated optimally in the long run.
1.10 Control of Thermal Energy Storage (TES) charging
The TES is part of the heating system.
0
Continuous storage operation This is mainly to ensure supply in case a heat
generator fails. By continuously storing heat
there is also a continuous loss of heat from the
storage tank.
1
2-sensor charging of storage The two storage sensors provide an indication
about the charging of the storage tank. With this
information switching heat generators can be
operated with fewer switching cycles and due to
that will run more efficiently. The thermal storage
losses will be reduced.
2
Load prediction based storage operation
Based on consumer demand predictions there
will only be as much charging of the storage as
needed. This allows for optimal operation of the
heat generator and reduces the thermal storage
losses maximally.