22
reflex ’servitec’
General description
Operation
General description
’servitec’ is a deaeration and make-up station. It can be used in a wide
range of system conditions. The main field of application are heating
and cooling circuits and wherever air problems interfere with systems
in form of dissolved or free gases.
’servitec’ vacuum spray-tube deaeration system removes up to 90% of
the dissolved gases from the mains content water. The ’servitec ../gl’
was developed for glycol water mixtures up to 50% glycol component.
With the type ../gl, high deaeration performances are also achieved
with glycol water mixtures.
Vacuum deaeration of a part flow of the circuit water takes place ac-
cording to an optimised schedule with selected deaeration programs
(→ p. 15).
A part of the circuit water is atomised into the vacuum spray-tube (20)
in which the vacuum is drawn through the pump (10). The large sur-
face of the sprayed water and the intense vacuum result in the very
high deaeration performance. The degassed water is returned to the
system by the pump (10). There the water is again able to dissolve
gasses. The gasses separated in the vacuum spray-tube are expelled
through the dipstick tube-deaeration unit (18). This deaeration interval
is repeated and both free as well as dissolved gases are removed from
the circuit water.
The deaeration interval
The water from the make-up or discharge line is made available at the
nozzle (14) at a constant pressure by way of the pressure reducing
valves (5, 8) and the connecting hose (15). The deaeration cycle is a
time-controlled process, which has been pre-programmed. Changing it
in the service menu is only possible by the Reflex service.
Injection time:
The pump (10) starts. A vacuum (dependent on temperature) can be read off the vacuum gauge (19) after a short time. This
is possible because the pump (10) draws more water from the vacuum spray-tube by way of the suction connection (17)
than is able to flow in by way of the pressure connection with nozzle (14). For this reason the pump (10) is set to a constant
working point by way of the overflow valve (3). Spraying through the nozzle commences as soon as the vacuum begins to
be established or, with the version „gl“, with the opening of the solenoid valve (7) of the overflow line.
The water level in the vacuum spray-tube (20) drops continuously while the pump (10) is running. The timing program and
pressure setting have been selected so that the water deficiency switch (16) will not be activated.
Pushing out time:
The pump (10) switches off. The water continuous to be sprayed into the vacuum spray-tube by the system pressure (at
least 1.3 bar). During the pushing out time (50 s) the water column in the vacuum spray-tube rises gradually. The vacuum is
still maintained during this phase of the cycle. At the end of the pushing-out phase the rising water column compresses the
removed gas within a few seconds, pushing it into the atmosphere by way of the dipstick tube-deaeration unit (18).
Idle time:
This is followed by the idle time during which re-deaeration takes place.
