Technische Alternative HZR 65, Operation And Installation Instructions Manual

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Installing instructions
Installing the sensor(s)
Correct arrangement and installation of the sensors is extremely important for correct func-
tioning of the system. It should be ascertained that the sensors are completely inserted in the
immersion sleeves. The threaded cable connections can serve as strain relief. Fundamentally
sensors should not be exposed to moisture (such as condensation) since this can diffuse
through the cast resin and damage the sensor. If this happens, heating the sensor to 90°C
for an hour might help. When using immersion sleeves in NIRO tanks (inoxydable) or pools
particular attention must be given to their
corrosion resistance .

Boiler sensor (boiler flow) : This sensor is either screwed into the boiler using an immer-
sion sleeve or attached to the flow line at a short distance to the boiler (see also "clip-on
sensors").

Buffer sensor : It is recommended to install the sensor in the upper part of the tank as a
reference sensor using the immersion sleeve supplied. The best position as reference sensor
for the load pump between the boiler and buffer is just above the return outlet. For tanks
without a screw-in facility for the immersion sleeve the sensor can be inserted under the
insulation against the wall of the tank if necessary. In this case attention should be paid to
achieving a long-term secure seating (e.g. cable fastening).

Clip-on sensor : Optimally secured using roll springs, pipe clamps or hose band clips to
the line. Make sure the material used is suitable (corrosion, temperature resistance, etc.).
Finally the sensor must be well insulated so that the exact pipe temperature is recorded
without being influenced by the ambient temperature.

Outdoor temperature sensor: This sensor is installed on the coldest wall (usually the
north side) approx. one to two meters above ground level. Temperature influences from
nearby air shafts, open windows, etc. are to be avoided.
Line extension
All of the sensor cables with a cross-section of 0.75mm2 can be extended up to 30m. Beyond
30m they can be extended by use of a suitably larger cross section. The sensor and the
probe can be connected by putting the heat-shrinkable tubing truncated to 4 cm over a wire
and twisting the bare wire ends.
The heat-shrinkable tubing is then pushed over the twisted bare ends and carefully heated
(e.g. with a lighter) until this has closed tightly around the joint.
Cable laying
In order to obtain interference-free signal transmission (to avoid measurement fluctuations)
the sensor lines must not be subject to interference factors. With the generally accepted use
of unshielded cables sensor lines are to be laid in their own cable channel at least 20 cm
away from mains cables.