Instruction of SR81 Split Pressurized Solar Hot Water System
Page 35 of 59
below the tank temperature and downwards to the switch-on temperature difference DTCO
of this cooling function, then system will be activated in order to cool down the tank by
releasing the energy through the collector.
If tank cooling function is activated, sign blinks on the screen
Note:
if tank temperature reaches to 95
o
C, all cooling functions will be locked.
Hysteresis switch on temperature difference is 5K.
OHDP Heat transferring by external radiator
Heat transferring by external radiator function is designed to transfer the excess heat which
is generated under the strong solar irradiation through an external heat exchanger (e. g. fan
coil); the purpose is to keep the collector’s or tank’s temperature within the operating range.
For this function, an extra output should be added (R2 or R3 as option)
Heat transferring by external radiator function can control either an additional pump or a
valve (
OTPM ON
= pump logic,
OTPM OFF
= valve logic).
Pump logic controlled thermal transferring function:
If the temperature (T1) of collector reaches the set point of switch-on temperature, pump
(R2/R3) will be triggered. If the temperature (T1) of collector drops below 5K to the over-heat
temperature, pump (R2/R3) will be ceased.
Valve logic controlled thermal transferring function:
If the temperature (T1) of collector reaches the set point of the switch-on temperature,
temperature difference circuit pump (R1) and valve (R2/R3) will be triggered simultaneously.
If the temperature (T1) of collector drops below 5K to the over-heat temperature, pump (R1)
and valve (R2/R3) will be ceased simultaneously.
Below is the example of this application for reference.
Collector valve logic heat transferring Collector pump logic heat transferring
Sign displays on the screen, it indicates that valve logic heat transferring is running.
Sign displays on the screen, it indicates that pump logic heat transferring is running.
