Installation manual
184
8.8
8.8 Contaminants in the Heating System
When installing a heat pump in a new or existing heating system,
the system should be flushed to remove deposits and suspended
matter. These types of contaminants can reduce the heat
transfer of the radiators, impede the flow or collect in the
condenser of the heat pump. In extreme cases, they can cause
the heat pump to switch off automatically. Oxidation products
(rust) can form if oxygen enters the heating water. Contamination
caused by remnants of organic lubricants and gasket material
can also occur frequently. Both sources of contamination can
lead - either individually or together - to a reduction in the
efficiency of the heat pump's condenser. In such cases, the
condenser must be cleaned.
Detergents should only be used with caution because of their
high acid content. The regulations of relevant employers' liability
insurance associations should be observed. Always consult the
manufacturers of the chemicals in case of doubt!
ATTENTION!
The heating system should be neutralized with suitable chemicals after
cleaning to avoid consequential damage.
The heat pump should generally be disconnected from the
heating system before flushing. Shutoff valves should be fitted in
the flow and return flow to prevent the heating water from
leaking. The water connections on the heat pump are used for
flushing.
In the case of heating systems equipped with steel components
(e.g. pipes, buffer tank, boiler, manifold, etc.), there is always the
danger of excess oxygen causing corrosion. This oxygen enters
the heating system via the valves, the circulating pumps and/or
plastic pipes.
NOTE
We therefore recommend equipping diffusion-open heating system with
an electrophysical anti-corrosion system. According to today's state of
knowledge, an ELYSATOR system is well suited for this kind of use.
8.9 Integration of Additional Heat Generators
8.9.1 Constantly regulated boiler (mixer regulation)
When implementing this type of boiler, the boiler water is always
heated to a set temperature (e.g. 70 °C) when the command is
issued accordingly by the heat pump manager. This temperature
must be set so high that domestic hot water preparation can also
be carried out using the boiler according to need.
Regulation of the mixer is undertaken by the heat pump
manager. If required, it calls for the boiler and adds more hot
water until the desired set return temperature or hot water
temperature is reached.
The boiler is called via the 2nd heat generator output of the heat
pump manager and the mode of operation of the 2nd heat
generator is coded as being “constant".
NOTE
When the special program heat generator 2 is activated, the boiler is
maintained at operating temperature for at least 30 hours after the
command is issued to prevent corrosion caused by short runtimes.
8.9.2 Variably-Regulated Boiler (Burner Regulation)
In contrast to the constantly-regulated boilers, variably-regulated
boilers supply hot water at a temperature which is directly based
on the respective external temperature. The three-way reversing
valve has no regulatory function. However, it has the task of
directing the hot water flow past or through the boiler, depending
on the operating mode. In the case of heat pump only operation,
the heating water is directed past the boiler to avoid losses
caused by heat dissipation of the boiler. No separate burner
regulation is required for bivalent systems because control can
be undertaken by the heat pump manager. If the system is
equipped with atmospherically controlled burner regulation, the
voltage supply for burner regulation should be disconnected in
the case of heat pump only operation. The boiler is controlled via
the 2nd heat generator output of the heat pump manager, and
the mode of operation of the 2nd heat generator is coded as
being “variable”. The characteristic curve of the burner regulation
is set according to the heat pump manager.
NOTE
It is not possible to control an additional immersion heater for
supplementary heating (E10.1) in a bivalent system.
Fig. 8.15: Circuit diagram for variably-regulated boiler operation
111
)ORZKHDWLQJ
)URP+3
*+