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Filling up
1.
Close all hot water taps.
2.
Open the commissioning valve (12).
3.
Open the cold water supply valve.
4.
When water flows from the commissioning valve (12), close the valve and continue to fill.
5.
Allow system to stabilise for five minutes.
6.
Open each hot water tap in turn to expel air from the system pipe work.
7.
Check for leaks.
8.
Manually operate Temperature and Pressure Relief Valve (5) to ensure free water flow through
discharge pipe. (Turn knob to left.)
Draining
Switch the electrical power off (important to avoid damage to element). Isolate boiler from OSO unit.
Turn off the cold water supply valve. Open hot water tap. Open drain (13). The unit will drain.
Safety Cut-out
1.
The safety cut-out operates if:
a.
Wiring is incorrect.
b.
The immersion heater thermostat or cylinder thermostat fails.
c.
Thermostat is set too high.
2.
Remember before resetting the safety cut-out or altering the thermostat setting, isolate electrical
supply to the unit prior to removal of the electrical box lid.
3.
Reduce thermostat setting and press the reset button. After adjustments are completed, ensure
the lid to the electrical box is replaced correctly and the retaining screw is fitted.
4.
If still out of operation, contact installer.
Cold or tepid water discharge from tundish
1.
Turn off the electrical supply to the immersion heaters.
2.
Turn off cold water supply valve.
3.
Open a hot tap.
4.
Drain water from commissioning valve (12) until water flow stops.
5.
Turn the knob on the Temperature and Pressure Relief Valve (5) to the left and hold in this
position until water flow stops from the commissioning valve.
6.
Close commissioning valve.
7.
Close all hot taps.
8.
Open cold water supply valve.
9.
Turn on electrical supply to the immersion heaters.
COMMISSIONING
SAFETY AND MAINTENANCE
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