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Subject to change without notice | 83051400cUK – Translation into English of the original German operating manual | ait-deutschland GmbH
Part 2 of VDI 2035 also points out the reduction in to-
tal salt content (conductivity). The risk of corrosion is
far lower if deionised water is used than is the case if the
system is operated with salty, i.e. softened water.
Even if the water has been softened beforehand, it con-
tains dissolved, corrosion-promoting salts, which act as
electrolytes due to the use of different materials in the
heating system and therefore accelerate corrosion pro-
cesses. This can ultimately result in pitting.
Contamination and deposits in the heating circuit can
cause malfunctions
RINSE, FILL AND BLEED THE HEATING CIRCUIT AND
HOT WATER BUFFER TANK
To bleed the hot water tank, the heating circuit and hot
water circuit must be rinsed simultaneously.
ON THE SAFE SIDE WITH LOW-SALT OPERATION
The problems listed above do not occur at all with low-
salt operation, as neither corrosive salts such as sul-
phates, chlorides and nitrates nor alkalising sodium hy-
drogen carbonate are in the heating water. The corro-
sive properties of deionised water are very low and in
addition, fur cannot form in the boiler. This is the ide-
al approach for closed heating circuits, in particular, be-
cause low oxygen input into the heating circuit can also
be tolerated.
In general, when the system is filled with deionised wa-
ter, the pH value sets itself within the ideal range due
to “self-alkalinisation”. If necessary, a pH value of 8.2
can be very easily alkalised by adding chemicals. In this
way, optimum protection of the entire heating system is
achieved.
MONITORING
Analytical recording and monitoring of the relevant
water values and the added active conditioning
substances is of decisive importance. Therefore, they
should be monitored regularly using appropriate water
test equipment.
Fill and bleed the heating circuit...
In addition, open the bleeding valve on the condens-
er of the heat pump. Bleed condenser.
Insulating the hydraulic
connections
Insulate the vibration decouplers and the pipes of the
heating circuit against vapour diffusion.
NOTICE
Insulate in accordance with applicable local
standards and directives.
ATTENTION
Install the outside pipes of the heating circuit be-
neath the frost line.
Check seals of all hydraulic connections. Conduct
pressure test...
Insulate all connections and lines of the heat circuit
and the heat source.
