Filling The System; Water Treatment - Bosch Condens 5000W Installation And Maintenance Instructions Manual

Commissioning
5.2

Filling the system

Before pressurising the system.
Additional expansion vessel fitted to the system.
The appliance integral expansion vessel is pre-charged to 75 kPa (equal
to a static head of 7.5m (22ft)). A Schrader type valve is fitted to the
expansion vessel to allow for pressure adjustment if required.
▶ If an extra expansion vessel is fitted to the central heating system,
ensure that it is set to the same pressure as the appliance internal
expansion vessel, refer to separate instructions supplied with the
extra expansion vessel.
▶ Check drain cocks are closed and all radiator valves are open. Add a
suitable inhibitor or combined inhibitor/anti-freeze, if the system is
exposed to freezing conditions, to the heating system water in
accordance with the manufacturers instructions.
▶ Turn on the water main and open the system valves.
▶ Open all radiator valves.
▶ Fill the system via an approved filling loop to between 150 and 200
kPa then turn the valve anti-clockwise to close.
Refer to figure 56.
▶ Vent [1] any air from the boiler heat exchanger using a suitable
container to collect any water. Ensure tube outlet [2] is directed away
from the fan or any other electrical component to prevent any water
damage. Also place a suitable cover over the fan to prevent any
spillage of water on to electrical connections. Ensure the cover is
removed after venting.
Fig. 56 Venting the boiler heat exchanger
▶ Vent all radiators, tighten when completed and check the system and
correct any leaks and correct if required.
▶ Briefly open the pressure relief valve to test its operation.
▶ If required increase system pressure back to between 150 to 200
kPa.
▶ Rotate the adjustable pointer on the pressure gauge to record the set
system pressure.
▶ Isolate and remove filling loop connection to system.
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1
2
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5.3

Water treatment

NOTICE:
▶ Artificially softened water must not be used to fill the CH system.
Flushing (CH):
▶ Switch off the boiler.
▶ Open all drain points and drain the system while the boiler is hot.
▶ Close drain points and add a suitable flushing agent at the correct
strength for the system condition in accordance with the
manufacturer's instructions.
▶ Run the boiler/system at normal operating temperature for the time
stated by the manufacturer of the flushing agent.
▶ Drain and thoroughly flush the system to remove the flushing agent
and debris.
Inhibitor (CH):
▶ Check drain points are closed and all radiator valves are open before
adding a suitable inhibitor compatible with aluminium (or combined
inhibitor/ anti-freeze if the system is exposed to freezing conditions)
to the heating system water in accordance with the manufacturers
instructions.
The pH value of the system water must be less than 8 or the boiler
warrantee will be invalidated.
▶ Fill system via an approved filling loop to between 150 and 200 kPa.
▶ Vent all radiators; tighten vents when complete.
▶ Vent any air from the boiler heat exchanger using a suitable container
to collect any water.
▶ Ensure tube outlet is directed away from the fan or any other
electrical component to prevent damage.
▶ Also place a suitable cover over the fan to prevent any spillage of
water onto electrical connections. Ensure the cover is removed after
venting.
▶ Vent all radiators.
▶ Re-pressurise if necessary.
▶ Set all controls to maximum.
▶ Record the date when the inhibitor was added to the system on the
warrantee card.
NOTICE:
▶ The concentration of inhibitor in the system should be checked every
12 months or sooner if content is lost.
▶ The addition of sealing agents to the system water is not
recommended as this can cause problems with deposits left in the
heat exchanger.
Bosch Condens 5000W – 6 720 646 195 (2018/10)