Baxi Potterton Solar - Manual (Page 17)

Potterton Solar - Solar Thermal Domestic Hot Water System 17
“Basic adjustment” “Programming”
14 -- 1 Start temperature max ºC
15 -- 5 Hysteresis Td in K
Timeframe (1…3) Start: min time
Timeframe (1…3) Stop: max time
Corresponding values in menu
“Basic adjustment” “Programming”
14 -- 2 Start temperature max ºC
15 -- 5 Hysteresis Td in K
Timeframe (1…3) Start: min time
Timeframe (1…3) Stop: max time
Corresponding values in menu
“Basic adjustment” “Programming”
--- Rotational speed min <100%
Corresponding values in menu
3.1.13 Rotational speed regulation
The solar circulation pump on 230V-outputs A1 and
A2 can be operated either in switch-mode (two-point
controller) or in a rotational speed regulated way.
If the rotational speed regulation is activated the pump
power is adjusted by a controller so that switch-on
temperature difference “Storage tank dTmax” is kept
constant as much as possible.At lower deviation of
“Storage tank dTmax” the pump is operated with the
lowest power till the switch-off wave is reached.
3.1.14 Thermostat (heating)
The thermostat is a control circuit that’s independent
from the storage loading.Thus an auxiliary heating in
the top area of the storage cylinder is made possible.
The output A3 will be:
• Switched on, when the temperature falls below the
adjusted start level.
• Switched off, when the temperature reaches the
adjusted start level + hysteresis.
3.1.15 Thermostat (cooling)
In order to optimise the energy yield, it could be useful
to “redirect” the solar energy, or to take it away from
the storage when the storage temperature reaches a
certain level.
When the sensor reaches the start temperature, output
A3 will be switched on.When the temperature level falls
below the start temperature hysteresis, the output A3
will be switched off.
Thermostat
(Storage top)
Heating on (A3)
T[ºC]
t
dT
10k
TTh
40ºC
on
A3
off