Viessmann VITODENS 300 WB3A, Service Instructions Manual

Page: 23 / 148

Filling the heating system
1. Check the charge pressure of the
diaphragm expansion vessel.
2. Close the gas shut-off valve.
3.
!
Important information
Unsuitable fill water
increases the level of depos-
its and corrosion and may
lead to boiler damage.
& Thoroughly flush the entire
heating system prior to fill-
ing with water.
& Only use fill water of pota-
ble quality.
& Soften fill water harder
than 20 °dH (3.58 mmol/l).
For suitable means of
water softening, see the
Vitotec pricelist.
& An anti-freeze additive sui-
table for heating systems
can be mixed with the fill
water.
Fill the heating system via the boi-
ler fill & drain valve
A
(minimum
system pressure > 0.8 bar).
4. Close the boiler fill & drain
valve
A
.
Further details regarding the individual steps
7
Initial start-up, inspection, maintenance
56
92
550
GB