Adjusting The Control Unit - Worcester Greenstar HIU Installation And Maintenance Instructions Manual

Commissioning
▶ Clean strainer ( chapter "Inspection and maintenance").
▶ Fill the system and check for tightness.
▶ Close the shut-off valves once the pressure gauge has reached
between 1 and 1.5 bar.
▶ Switch on the power supply.
▶ Ensure the correct primary flow rates are available to the HIU (
chapter Heat meter (Option)).
Control valves: the valves can be fully opened via the service function
. The valve is calibrated first and then after 10 seconds the valve is
opened for 10 minutes. When the power supply is interrupted, the valves
remain in position.
When the air vent valves are opened, water may be discharged from the
valves.
▶ Collect discharging water with a vessel or cloth.
To vent the DHW circuit:
▶ Open the water tap. Open the air vent valve on the DHW heat
exchanger to allow air to escape.
To vent the secondary circuit (heating circuit):
▶ Open the thermostatic valves to open the control valve.
▶ Vent the radiators.
To vent the heating circuit:
If the heat meter is reading Error Code E7 the venting process needs to
be repeated ( page 16).
▶ Open both control valves with the service function
vent valve on the heating circuit heat exchanger to allow air to escape.
▶ Make sure that the air vents are fully closed after venting.
Fig. 29 Manual vent points
Overall system
Air bound in the water is only released after a specific time as a result of
pressure fluctuations as well as solution and degassing processes.
▶ After 1-2 weeks, vent the system again and top up if required.
▶ Vent at every highest point in the system.
7.2

Adjusting the control unit

The LED On/Off indicators of the module are visible through the
enclosure.
14
Fig. 30 LED On/Off indicators, rotary selectors on the control unit
If different values are set at the control unit and the room controller (e.g.
Sense II), the lower value is used for control.
To set the required set DHW temperature, observe the DHW output.
CIBSE CP1 recommends for the DHW temperature to be set at 50. (
Specifications).
control unit LED display
▶ Set the required values at both rotary selectors.
. Open the air
LED red
LED yellow
LED green
LED flashes red Invalid position (bypass, DHW and circulation pump
LED flashes
yellow
LED flashes
green
00
30 - 60 (35 - 70) Setting the temperature
Table 13 LED displays and positions on rotary selectors
Calibration of the control valves is not required during commissioning -
only when a control valve fault is displayed ( chapter "Faults").
Description
 Fault chapter
Rotary selector at 00
Rotary selector at 30 - 70:  Fault chapter
Normal mode with set value (30 - 70)
function, heating function deactivated)
Heat interface unit starts
Calibration or Service mode (
Calibration and test mode of the control valve (once
10 seconds have elapsed, the valve is opened for 10
minutes).
Service mode of DHW circulation pump
Heating circuit without mixer.
For the heating circuit without mixer the rotary
selector must be at this position!
Function off
Greenstar – 6721852556 (2022/11)
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