Draining The Boiler On The Heating Water Side - Viessmann Vitodens 222-F Installation Instructions For Contractors

Troubleshooting
Maintenance
(cont.)

Draining the boiler on the heating water side

!
Please note
Risk of scalding.
Residual water will escape when the boiler or
one of the following components is fitted or
removed:
■ Water-filled pipework
Circulation pumps
■
Plate heat exchanger
■
■ Components fitted in the heating water or
DHW circuit
Water ingress can result in damage to other
components.
Protect the following components against
ingress of water:
Control unit (in particular in the service posi-
■
tion)
■ Electrical components
■ Plug-in connections
■ Cables and leads
Only drain the boiler or heating system when the
boiler water or cylinder temperature has drop-
ped below 40 °C.
A
Fig. 43
1. Close the shut-off valves on the heating water side.
2. Route hose at drain valve
tainer or drain outlet.
68
into a suitable con-
A
3. Open drain valve and drain the boiler as much
A
as required.