Wamsler K148, Operating And Instruction Manual

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Up to a static height of 10 m, the capacity pressure expansion vessel is dependent on the
water capacity of the system as follows:
Water content Vessel size
Litre Litre
up to 111 12
112 - 167 18
168 - 231 25
232 - 324 35
325 - 463 50
464 - 741
80
There should no manually operable shut off valves installed between the expansion vessel
and the stove.
A ventilation section at least 0.5 m above the highest circulation point in closed systems
with a diameter of at least 1
″
should be arranged and a ventilation valve provided at the
upper end.
In gravity systems the rise and fall of horizontal pipes should be at least 0.5 cm/m.
Radiators with more than 25 ribs or plate heat exchangers over 1.5 m long should be di-
agonally connected to the flow and return pipes.
Where there is a lower distribution ventilating valve it must be provided on each radiator.
The radiators should not be inclined towards the ventilation. As radiators are usually at the
same level on the floor where the stove is installed, these radiators should all be connected
to a circulating pump as matter of course.
If however a pure gravity plant has to be executed without pumps, then the centre of the
radiator should not be lower than the centre of the boiler.
In the simplest installation case, the circulation pump is connected to the mains by a switch
and runs continuously during the heating period, while the water capacity of the stove is
regulated by an integrated temperature controller.
The pumps can however also be controlled from a maximum-thermostat in the domestic
water boiler, to ensure a minimum temperature for the domestic hot water.
It is also possible to switch the circulating pumps through a room thermostat. In this case
however the gravity circulating domestic water boiler should not have a capacity of less
than 260 l, if there are no other radiators on gravity circulation are connected.
Independently of the control types described above, the heating circulation and/or boiler
loading pump should primarily be controlled through a thermostat with a fixed switch on
temperature of between 50 and 55 °C, situated immediately at the stove's return flow con-
nection following an adjustable bypass close to the stove between the flow and return
lines, to avoid a low temperature operation of the stove boiler.
In the installation unit which can be supplied as an accessory there is a thermal boiler
monitor integrated as a continuous regulating valve. The pump controls mentioned above
are then not needed.