4.1
Replacing the bellows seal
If the packing leaks, this is due to a dam-
aged bellows seal.
The entire bellows assembly together with
the packing (4.2) must be replaced.
We recommend renewing the top seal (5.3)
and the bottom body gasket (1.2) of the bel-
lows housing as well.
Mixing and diverting valves in nominal sizes
DN 32 to 80 differ from one another in the
arrangement of their plugs and sleeves (see
Fig. 4), where as mixing and diverting
valves in nominal sizes DN 15 to 25 have
the same plug and sleeve arrangement.
4.1.1 Disassembly
1. Unscrew the stem connector nut (6.1)
and lock nut (6.2) from the plug stem of
valves in DN 50 or smaller.
2. Unscrew the coupling nut (5.1) from the
bellows housing. Remove the nuts (1.1)
and lift off the flange (5.4).
3. Pull the bellows housing (5.2) with the
bellows assembly out of the body as far
as they will go. Place an open-end
wrench (SW 10 for
£
DN 50 or SW 13
for
³
DN 65) at the side on the hexagon
(X) or at the flattened area of the plug
stem to hold it stationary. Undo nut (12)
and remove wrench.
4. Unthread nut (12). Remove the two lock
washers (12.2) and washer (12.1).
5.
DN 15 to 25:
Carefully pull the plug stem (6) together
with the bellows assembly (5) and bel-
lows housing (5.2) from the top out of
the valve body.
DN 32 to 80:
Keep the bottom plug of diverting valves
or the bottom sleeve of mixing valves on
the plug stem. Use a long screw (M8 for
nominal sizes DN 32 to 50 and M12 for
DN 65 and 80) to keep the plugs (3.x)
and sleeves (10.x) in the right order.
Carefully lift the plug stem together with
the bellows assembly (5) and bellows
Maintenance–replacing parts
10
EB 8135/8136 EN
AB
A
B
12.2
12
12.1
1.1
6.1
6.2
5.3
5
5.2
X
5.4
1.2
4.2
4.3
5.1
3.2
Fig. 4 · Mixing valve DN 32 to 50