Salus PCSol 201, Installation And Operation Manual

Page: 16 / 56

16
13. SOLAR APPLICATIONS
13.1. Night cooling
Due to the fact that in solar thermal
schemes
C , F , I there is no risk of
reservoir overheating and that other
protection means are provided for them
against overheating, the function of night
cooling is not available in these schemes.
For correct operation of night cooling it is
required that the clock is set.
Night cooling function is used to cool
DHW reservoir by emitting excess heat through
cold collector. It is done by starting the collector
pump.
During night cooling, any alternative
sources of energy will be switched off.
There are three settings for night cooling
function: Night cooling, Night cooling ON,
Night cooling OFF and they are in
“
Adjustment
”
menu.
Night cooling- YES: switches on, NO: switches
off the night cooling mode. When the mode
is on, the controller, in hours 0
00
÷5
00
, if T2
sensor temperature is higher than specified
in
Night cooling ON setting; will decide to
start night cooling. The controller will start
the collector pump in order to discharge to
reservoir and will be cooling the reservoir to
reach
temperature specified in Night
cooling OFF setting. In this mode, the
controller additionally monitors the collector
temperature; cooling will be stopped for
some time, if
T1+dToff>T2 . Regardless
prior conditions, the controller will exit from
the cooling mode at 5
00
and return to normal
operation. Activation of night cooling mode is
indicated in the screen as blinking moon icon
near the collector picture.
Night cooling ON - DHW reservoir temperature
(measured by T2 ), when reached, if night
cooling function is enabled (prior item)
0
00
÷5
00
and the temperature at T2 sensor is
higher than Night cooling ON temperature ,
the controller will decide on night cooling
activation. The controller will start the
collector pump to discharge the reservoir and
it will continue to cool the reservoir to the
temperature set for
Night cooling OFF .
Night cooling OFF - DHW reservoir
temperature ( T2 sensor), to which the
controller will be cooling the reservoir during
night cooling function. When the temperature
drops to the one specified for
Night cooling
OFF , the controller will stop night cooling.
Additionally, depending on selected scheme,
the controller will control additional outputs, so
as to discharge heat more efficiently.
In scheme B during night cooling, circulation on
output P2 will be activated (regardless any time
programs etc.); heater operation will stopped
(output
H is turned off, regardless any time
programs etc.).
In schemes D, E, G, J, K, L, M during night
cooling, circulation on output H will be activated
(regardless any time programs etc.).
13.2. Solar thermal scheme A
Loading of DHW reservoir with solar collector.
This basic solar application.
Fig. 13.1 Solar thermal scheme A
The collector pump will be started with
100% capacity, when difference between T1 and
T2 exceeds value of dTonDHW
setting and it will be working for the time
specified in
tP setting. If upon this time the
difference between T1 and T2 is still above
dTonDHW, the pump speed will remain at
100%. If the temperature difference between T1
and T2 drops below dTonDHW, the controller
will start reducing the pump speed, until the
moment
when T1
and T2 difference reaches value specified in
dToffDHW setting. When T1 and T2 difference
is between the values dTonDHW
÷
dToffDHW ,
the controller will calculate and set the pump
speed
proportionally. When dToffDHW is
reached, the pump will work at minimal speed
(parameter
Pmin ), below it will be stopped.
System will work by the time when T2
sensor preset temperature TsDHW is reached,
than the collector pump P1 is stopped.
If the collector temperature T1 reaches
critical value ( TCOLcr parameter), the controller
will allow the collector pump to be switched on to
lower the collector temperature below
HP1
hysteresis parameter.
If the reservoir temperature on T2 sensor
reaches the value of TDHWmax, than the
controller, despite critical collector’s temperature
( TCOLcr ), will stop the collector pump, disabling
the collector cooling. It is to protect the reservoir
from overheating.