oventrop Regtronic RQ Installation And Operating Instructions For The Specialised Installer page 26

The thermal disinfection process
1. Store preheating
2. Primary pump speed control to reach dis-
infection temperature
3. Store afterheating, if necessary
4. Stabilisation and heating-up of the circula-
tion pipe
5. Disinfection of the circulation pipe
6. Overrun
R4
S1
S2
secondary side
Primärseite Sekundärseite
The thermal disinfection function can be started
by means of the Preheating option in order to
heat the store up to a sufficient temperature level
before the thermal disinfection begins. Regardless
of that, afterheating is started if an insufficient store
temperature is detected during thermal disinfection
(see page 24).
26
When the preheating option is activated, the thermal
disinfection will start automatically 30 minutes before
the adjusted Disinf time with store afterheating.
When the thermal disinfection function is started
manually, it will also begin with store afterheating.
For store afterheating, the reference sensor of the
main function Afterheating is used. As soon as the
required afterheating set temperature is exceeded at
the reference sensor, preheating is completed.
The controller will now control the primary pump
such that the temperature required for disinfection
is provided, and will monitor the temperature at
R2
the S1 store flow sensor. If the temperature at S1 is
sufficiently high for disinfection, the controller starts
stabilising the circulation pipe temperature. If the tem-
perature is insufficient, the controller starts afterheat-
ing again with a higher afterheating set temperature
and then monitors again, whether the temperature
at sensor S1 is sufficiently high for disinfection. The
increased afterheating set temperature is limited by
the parameter Boiler max..
If the temperature at sensor S1 is sufficiently high for
disinfection and the controller starts the circulation
pipe stabilisation, the temperature T-CW at the
circulation return sensor is monitored. The circula-
tion pump is activated during this process. If the
temperature measured at the circulation return sen-
sor reaches the required temperature T -disinf set,
circulation pipe stabilisation is considered complete
and fully heated, so that the actual thermal disinfec-
tion can begin.
The controller now aims to keep the required set
temperature at the hot water flow sensor S2 and
starts the Disinf. duration countdown. For keep-
ing the required temperature at the S2 sensor, the
parameter ∆T circ is taken into account in order to
compensate the temperature loss of the circulation
pipe between flow and return (page 23). When
the countdown Disinf. duration reaches the adjusted
value Disinf. duration, the thermal disinfection is
considered as completed.
Now the Overrun starts. The primary pump and
the circulation pump remain active for the adjustable
Overrun time. In order to flush a further pipe line,
the additional Overrun option can be activated if
there is a free relay available. When the additional
option is activated, the allocated relay is energised
during the overrun time.
When the overrun time has elapsed, the overrun and,
if activated, the flushing (Flushing time) ends.
The thermal disinfection is now fully completed.