5
x
Control unit operation
30
FA ROTEX Solaris RPS3 25M - 03/2010
5.2.1 Pump operation
The Solaris system is operated throughout the year, without the need for manual intervention. The operation of the pump is
controlled by the Solaris R3 controller. The operating and display elements are shown in Image 5-1.
Criteria for switching on:
– Pump operation depends on the continuously measured difference between the
collector (T
K
) and return (T
R
) temperatures compared to the value set under the "Delta T On" parameter.
– The circulation pump and, where installed, the booster pump, switch on when the temperature difference (=T
K
– T
R
) exceeds
the value set under parameter "Delta T on" (e. g. Return temperature = 40 °C and "Delta T on" = 15 K; Solar panel temper-
ature > 55 °C).
– Where it is installed, the operation of the booster pump (P2) is dependent on the set parameter value "Time P2" in [s].
If the correctly adjusted FlowSensor measures a stable flow rate before this time has elapsed, the Solaris system is
completely filled with water.
– Automatic switchover from two pumps to one pump (circulation pump P1) and vice versa if the optional booster pump (P2)
has been installed.
Criteria for switching off:
– The pump(s) switch off when the temperature difference falls below the value set under the parameter "Delta T off".
1st possibility:
Normal switch-off when the "Filling time" ("Time P2" parameter) has elapsed and the difference between
flow and return temperatures reaches the switch-off condition (T
V
– T
R
<"Delta T Off").
2nd possibility:
Rapid switch-off if the collector is cooling too quickly (T
K
– T
R
<"Delta T Off") during the "Filling time"
("Time P2" parameter).
– The maximum storage tank temperature set via the "T
S
max" parameter is reached (T
S
light flashes). In this case, the pump(s)
can only be switched on again if the storage tank temperature drops by more than 2 K.
– The maximum permissible collector temperature set by the "T
K
perm" parameter is reached (T
K
light flashes). In this case,
the pump(s) can only be switched on again if the solar panel temperature has fallen more than 2 K below parameter
value "T
K
perm".
– Defective FlowSensor.
5.2.2 Booster function for high solar panel temperatures (only if a booster pump is connected)
If the optional booster pump P2 is installed in the collector circuit, it is switched on in addition to the normal circulation pump P1
when the solar panel temperature reaches "T
K
max" = 70 °C (booster temperature).
This increases the system pressure as well as the flow quantity, which enables more heat to be stored within a shorter
time.
A heating technician can change the booster temperature by means of the "T
K
max" parameter. As soon as the collector temper-
ature drops more than 5 K below “TK max”, pump P2 is switched off automatically again.
A rapid switch-off will not take place if the frost protection is active (T
K
<0 °C within the last 24 h). The cir-
culation pump and, where installed, the booster pump, are operated over a longer period to heat the connection
pipes to a temperature where no ice can form.
In this case, however, a considerably higher collector temperature must be reached before the pumps switch
on.