Starting The Appliance; Single Pipe Gravity Feed Systems; Double Pipe Sub-Gravity Feed Systems And Single Pipe Suction Lift With De-Aerator - Bosch WORCESTER Greenstar Heatslave II External 12/18 Installation, Commissioning And Servicing Instructions

Commissioning
If an extra expansion vessel is fitted to the central heating return, adjust
this to the same pressure as the appliance internal expansion vessel,
refer to separate instructions supplied with the extra expansion vessel.
4. Open all system and radiator valves.
▶ Turn on the water main stop cock.
▶ Close the flow pipe manual air vent when water is vented.
▶ Fill the system to between 1 and 2 bar pressure via a WRAS approved
filling link. Monitor the pressure gauge during venting and
repressurise if required.
▶ Check air is being discharged from the automatic air vents.
▶ Vent all radiators, retighten when completed, check the system and
correct any leaks.
▶ Bleed air from both of the secondary heat exchanger air vents [B]
and flow pipe air vent.
▶ Bleed air from the pump using the pump bleed screw.
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B
B
Fig. 57
5. Connect a suitable hose to the Heatslave tank drain.
Open the drain valve to reduce the system to the correct pressure,
then close the drain valve. Ensure safe disposal of the discharge.
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Fig. 58
6. Check system and rectify any leaks.
6.3

Starting the appliance

NOTICE:
Never run the appliance when the appliance/system is
unpressurised or empty.
1. Check the oil supply is correctly fitted, pressure tested and in good
working order before turning on the oil supply valves to the boiler.
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▶ Turn on the main oil supply valve at the tank and draw off at least
2.5 litres of oil until a steady flow of clear uncontaminated oil can be
seen as follows:
– The oil supply to the boiler should be primed before the burner is
operated to avoid unnecessary pump wear.
– The use of an oil suction pump will prime and flush through any oil
supply set up simply and easily, alternatively the following
procedures can be used.
6.3.1

Single pipe gravity feed systems:

▶ Disconnect the flexible oil hose and open the isolating valve to
discharge the oil into a suitable container.
▶ If a top entry tank has been used the pipework will need to be primed
before the oil will discharge under gravity.
▶ When completed, close the isolating valve, reconnect the flexible oil
hose.
When the oil reaches the pump, bleed the air from the pump:
▶ Open the isolating valve and the oil pump bleed port [1] to discharge
into a suitable container once the boiler is started up.
▶ Switch on the electricity supply to the boiler.
▶ Set the programmer to ON for CH and DHW.
▶ Turn on the boiler CH control thermostat.
▶ Allow the burner to run through to lockout indicated by the control
panel LCD display [J] showing code 9F 855.
Fig. 59
[1] Bleed and pressure gauge port
[2] Vacuum gauge connection
[3] Pressure adjuster
[4] Cover retaining screws x4
If no oil comes out of the port valve [1], then re-prime the oil line as
detailed above
▶ Wait 2 minutes then press the lockout reset button .
▶ Repeat the procedure until a steady stream of oil without air, runs
from the bleed port, then lock bleed port [1].
▶ Switch off the boiler.
6.3.2 Double pipe sub-gravity feed systems and single pipe
suction lift with de-aerator:
▶ Prime the oil supply pipework to prevent oil pump damage.
▶ To prime a de-aerator [2], disconnect the flexible oil inlet hose [7]
from the isolation valve and place in a container of heating oil[6].
Connect a spare flexible oil hose [5], to discharge into container [6].
Open the isolating valve, turn on the power to the boiler and set the
programmer to ON. Prime the de-aerator until there is a steady flow
of oil into container [6]. Turn off the boiler then reconnect the
flexible oil inlet hose [7].
▶ Turn on the boiler, the oil level in the de-aerator will drop whilst the
oil is being drawn from the tank. If the de-aerator empties and the
burner locks out before the oil is drawn from the tank, you will have
to prime the de-aerator again.
Greenstar Heatslave II External
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6720821683-11.1Wo
2022+ 6 721 843 980 (2022/01)