eta 13180 LP-D, Руководство по установке

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Information for installation Pressure equalisation
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recommended here. If damage to the boiler caused by
the introduction of oxygen is proven, all claims under
warranty and guarantee are void.
Fig. 7-7: System separation
1 Heat exchanger
2 Control valve
The hydraulically correct incorporation of the heat
transfer station (regardless of whether for system
separation or as a transfer station) must be adjusted
on the primary side. In order to achieve optimal flow
based on the flow temperature, the use of a two-way
control valve (see graphic above) is recommended.
Additionally, the primary pump should be designed
with differential pressure control. A system separation
module with these specifications is available from ETA.
Fig. 7-8: ETA system separation module
No open expansion tanks
Open expansion tanks improperly allow air into the
system. Existing systems with open expansion tanks
must be redesigned or physically separated from the
boiler.
Pressureless buffer storage may not be attached
directly to the boiler. If it is not possible to replace
this buffer, there must be a physical separation
between the boiler and the pressureless buffer.
7.6 Pressure equalisation
An expansion tank is needed
To equalise pressure in the system, a diaphragm
expansion tank with a gross capacity of around 10% of
the system volume is required. If the pressure
difference between cold and warm heating system
(buffer fully loaded if installed) is greater than 1.0 bar
for a single-storey system or 0.5 bar for a three-storey
system, then the expansion tank is too small and
absolutely must be replaced with a larger one. If the
installed expansion tank is not large enough, the
system sucks in air when cooling and the air is
absorbed by the cold water and transported to the
boiler. At the point of highest temperature, the air
separates from the water again. This usually takes
place in the boiler, and the inevitable result is that the
boiler wall will rust through in these spots.
Adjust expansion tank preset pressure
Most expansion tanks are delivered with primary
pressure of 1,5 bar. Adjust the pressure by releasing
nitrogen so that it is 0.3 bar higher than the static
pressure at the installation location, but make sure the
pressure does not fall below 0.9 bar.
•
Example 1:
height difference between expansion tank and
highest point in the system pst = 11 m = 1.1 bar:
1.1 bar + 0.3 bar = 1.4 bar pressure setting.
• Example 2:
height difference between expansion tank and
highest point in the system pst = 5 m = 0.5 bar:
0.5 bar + 0.3 bar = 0.8 bar -> 0.9 bar pressure
setting.
Here, the minimum pressure of 0.9 bar must be
selected. The factory setting of 1.0 bar for the cut-
off pressure is compatible with this minimum
pressure setting.
Protect the expansion tank against shut-off
All shut-off valves along the path from the expansion
tank to the boiler and to the buffer storage tank must
be capped valves, or the hand wheels or levers must