Water Quality And Heat Transfer Medium; Dhw Connection (To Din 1988) - Viessmann VITOCAL 222-G Technical Manual

Design information
Drain line for safety valve

Water quality and heat transfer medium

DHW
The appliances can be used with potable water up to 20 ºdH
3
(3.58 mol/m ). In case of higher hardness levels, a softening system
for potable water is required on site to protect the integral plate heat
exchanger.
Heating water
Regarding the quality and amount of heating water, including fill and
top-up water, observe the VDI 2035 [or local regulations].
■ Thoroughly flush the entire heating system prior to filling it with water.
■ Only use fill water of potable quality.
■ Soften fill water with a hardness above 16.8 °dH (3.0 mol/m
with a small softening system for heating water (see the Viessmann
Vitoset pricelist).
12

DHW connection (to DIN 1988)

For the DHW connection, observe DIN 1988 and DIN 4753.
A DHW
B DHW circulation pump
C Spring-loaded check valve
D Hydraulic connection array (plan view)
E Expansion vessel, suitable for drinking water
F Visible blow-off line outlet
G Safety valve
H Shut-off valve
*4 According to DIN 1988-2, a drinking water filter should be installed in systems with metal pipework. We also recommend the installation of a
drinking water filter when using plastic pipes, as per DIN 1988, to prevent contaminants entering the DHW system.
VIESMANN
56
(cont.)
3
), e.g.
Provide a drain line to drain safety valve A on the heating side.
Heat transfer medium for solar circuit (only for
Vitocal 242-G/343-G)
■ Only fill the solar circuit with Tyfocor LS heat transfer medium (frost
protection down to −28 ºC). Never dilute the heat transfer medium
with water.
■ Provide an expansion vessel for the solar circuit, sized in accordance
with the details on page 72.
■ Never use zinc-plated/galvanised pipes for the brine or the solar cir-
cuit (only for the Vitocal 242-G).
K Flow regulating valve
L Pressure gauge connection
M Non-return valve/pipe separator
N Drain valve
O Cold water
P Drinking water filter *4
R Pressure reducer
VITOCAL