6| Commissioning the heating system
6 720 648 163 (2011/05)
3 Commissioning the heating system
3.1 Turning the heating system on
Before switching on, ensure that:
•the operating water pressure is sufficient,
•the fuel supply has been turned on at the main shut-
off valve, and
•the heating system emergency shut-off switch is in
the ON position.
3.2 Checking the operating pressure,
topping up the boiler water and
bleeding air from the system
The water used for filling the heating system loses a
substantial amount of volume in the first few days due to
the release of its gas content. This causes air pockets to
form and the heating system starts to make noises.
BWith new heating systems, check the operating
pressure daily at first, topping up the boiler water and
bleeding the system and radiators (if so equipped).
BLater on, check the operating pressure monthly,
topping up boiler water and bleeding the boiler and
radiators (if so equipped).
3.2.1 Checking the operating pressure
Your heating contractor will have set the system to the
required operating pressure of at least 15 psi (1 bar) and
entered the setting in Tab. 1, page 7.
BRead the current operating pressure (psi/bar) and
temperature (°F/°C) from the temperature/pressure
gauge.
BIf the temperature/pressure gauge needle drops
below the minimum pressure marker of 15 psi (1 bar),
the operating pressure is too low. Top up the system
until the contractor's selected operating pressure is
reached.
Fig. 2 Pressure/temperature gauge
3.2.2 Topping up the boiler water and bleeding the
system
Ask your heating contractor to show you where the
boiler fill & drain valve for topping up the heating system
is located in your heating system.
BIf there the fill valve is not hard piped to the water
supply, you will need to connect a hose.
BFill the heating system by slowly opening the fill valve.
Observe the pressure gauge (pressure/temperature
gauge) while doing so.
BClose the boiler fill valve once the required operating
pressure has been reached.
BBleed the system via the air vent and the radiator
bleed valves (if so equipped).
BTop up with additional water if the pressure drops as
a result of bleeding the system.
7 747 010 720-24.2RS
CAUTION: Health risk from contaminated
domestic water.
BIt is imperative that you observe all
regulations and standards applicable in
your country regarding prevention of
domestic water contamination.
CAUTION: Risk of damage to system due to
temperature stress.
If you fill the heating system when it is hot,
the resulting temperature stress can cause
stress cracks and a leak in the boiler.
BOnly fill the heating system when cold
(the flow temperature should be no more
than 100 °F (30 °C)).
CAUTION: Risk of system damage due to
frequent topping up.
If you have to top up the heating water
frequently, the heating system may suffer
damage from corrosion or scaling due to
repeated introduction of oxygen.
BAsk your heating contractor if the local
water can be used untreated or whether
it needs to be treated.
BNotify your heating contractor if you find
you need to top up your heating system
frequently, as there may be a leak.
