Bosch DOMESTIC HOT WATER HEAT PUMP Technical Manual page 42

In the NTC sensor, in contact with the pipe of cold water from the bottom of the storage tank, and in the NTC
sensor, in the pocket of the hot water from the top of the tank, the thermal paste "Wacker" (part nr 8 719 918 658)
must be used to ensure an efficient contact and consequent efficient temperature sensing.
Condenser Maintenance - Descaling procedure
The process of descaling in the condenser of plate heat exchanger type can be done in the place, with no need of
removing the component. In cases where water flow from tank to the condenser plate heat exchanger is blocked
with debris, lime scale or other substances, it is strongly recommended the use of a pump, by the technical service.
Picture 47 shows one example of a recommended pump, from the supplier Sanit.
(Available models: KalkMax 500 or 800)
Pict.48 – Sanit Kalkmax pump
According to the supplier of the condenser (SWEP), with this type of components it can be used a liquid such as
Kaloxi.
This cleaning compound especially developed to dissolve and remove the internal deposition of scale forming salts
in water supplied systems is caustic, with a pH-value of 1,5 and it consists of 9% of Phosphorous acid, 35% of
citric acid and 1% of inhibitor with 55% of water. The waste of this cleaning liquid should be neutralized to PH7.
These acids are bio-degradable and non-toxic and remove all types of scale as well rust that can be accumulated
inside of heat exchangers obstructing water flow and reducing heat transfer. The inhibitor makes this product work
as a buffer and protects all the sensitive components you find in heat exchangers and in complete heating or
cooling systems.
6720649497 SM HP270-1 2012/09 en
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