Instruction of SR91 Split Pressurized Solar Hot Water System
Page 30 of 49
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).
Heat transferring by pump logic:
If the collector temperature reaches the switch on temperature (OTST), the heat transfer
pump(R2/R3) on. If the collector temperature fall 5K below heat transfer temperature
(OTST), the heat transfer pump (R2/R3) off.
Heat transferring by valve logic:
If the collector temperature reaches the switch on temperature (OTST), the heat transfer
valve(R2/R3) and circuit pump(R1) on. If the collector temperature fall 5K below heat transfer
temperature (OTST),the heat transfer valve(R2/R3) and circuit pump(R1) off.
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.
Note:
1. When collector overheat temperature OTST is 10K below the CEM temperature of
collector emergency shutdown, then collector overheat temperature OTST is locked
2. Heat transferring function is only available when collector cooling function (OCCO) is
deactivated.
