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EN
4. SAFETY VALVE LEAKAGE
CAUSE
SOLUTION
Excessive pressure in the system that causes
the safety valve to open
With the system cold, restore the heat-transfer fluid in the system, raise it to the right pres-
sure and then bleed the system when hot.
Pre-charge pressure too low or too high in the
expansion vessel
Adjust the pre-charge pressure in the solar expansion vessel to 0.3 bar less than the sys-
tem’s cold charge pressure.
Expansion vessel too small
Replace the expansion vessel and have a larger one installed (by the installer).
5. CONTROL UNIT DISPLAYS INCORRECT VALUES
CAUSE
SOLUTION
Temperature sensor incorrectly mounted
Mount the sensor correctly or replace it if burnt out.
6. HIGH TEMPERATURE OF THE COLLECTORS DURING THE NIGHT
CAUSE
SOLUTION
Temperature sensor incorrectly mounted
Mount the sensor correctly or replace it if burnt out.
Non-return valve of the solar unit seized
Free up the non-return valve of the solar unit.
7. HIGH CHANGES IN PRESSURE
CAUSE
SOLUTION
Excessive pressure in the system that causes
the safety valve to open
With the system cold, restore the heat-transfer fluid in the system, raise it to the right pres-
sure and then bleed the system when hot.
Pre-charge pressure too low or too high in the
expansion vessel
Adjust the pre-charge pressure in the solar expansion vessel to 0.3 bar less than the sys-
tem’s cold charge pressure.
Expansion vessel too small
Replace the expansion vessel and have a larger one installed (by the installer).
8. THE WATER IN THE CALORIFIER COOLS CONSIDERABLY DURING THE NIGHT
CAUSE
SOLUTION
Temperature sensor incorrectly mounted
Mount the sensor correctly or replace it if burnt out.
No insulation
Insulate the system adequately using specific insulating material for solar systems.
Non-return valve of the solar unit seized
Free up the non-return valve of the solar unit.
9. HIGH TEMPERATURE IN THE SOLAR COLLECTORS
CAUSE
SOLUTION
Air in the system
With the system hot, bleed the air relief valve on the collectors and the degasser on the
solar unit. Repeat the operation for a few days.
Pump seized up
Open and close the pump to free it up, or replace it if necessary.
Dirt in the pump
Dismantle the motor and clean it.
Incorrect pump assembly
Mount the pump correctly.
Pump speed range incorrectly set.
Always set the pump to the third speed (the pump speed is controlled by the control unit).
Excessive pressure in the system that causes
the safety valve to open
With the system cold, restore the heat-transfer fluid in the system, raise it to the right pres-
sure and then bleed the system when hot.
Temperature sensor incorrectly mounted
Mount the sensor correctly or replace it if burnt out.
Control unit set incorrectly
Set the control unit as explained in the instructions accompanying the device.
No supply voltage
Check the fuse in the control unit and in the fuse box.
Shutters in the solar unit closed
Open all the shutters of the solar unit.
Pre-charge pressure too low or too high in the
expansion vessel
Adjust the pre-charge pressure in the solar expansion vessel to 0.3 bar less than the sys-
tem’s cold charge pressure.
Expansion vessel too small
Replace the expansion vessel and have a larger one installed (by the installer).
