5
Sensor installation
Correct arrangement and installation of the sensors is extremely important for correct functioning of
the system. To this end, also ensure that they are completely inserted in their sensor wells. The cable
fittings provided serve as strain relief. When used outdoors, no water must be allowed to penetrate
the sensor wells (
risk of frost
). The contact sensors must be insulated well to protect them from be
-
ing influenced by the ambient temperature.
Sensors should generally 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 may help. When using sensor wells in stainless steel cylinders or swimming pools, particular
attention must be given to their corrosion resistance.
•
Collector sensor (grey lead with junction box):
Either insert into a pipe which is brazed or riveted
directly to the absorber and protrudes from the collector housing, or insert a tee into the flow
manifold of the outermost collector into which the sensor well, together with the brass cable fit
-
ting (= protection against moisture), can be inserted; then insert the sensor. To protect against
lightning damage, the junction box has a surge protection (voltage dependent resistor) which is
clamped in parallel between the sensor and the extension cable.
•
Boiler sensor (boiler flow):
This sensor is either inserted into a sensor well in the boiler or fitted
to the flow line as close to the boiler as possible.
•
DHW cylinder sensor:
The sensor required for the solar thermal system should be used with a
sensor well for finned tube heat exchangers just above the exchanger or, if integrated smooth
tube heat exchangers are used, in the lower third of the exchanger or the exchanger’s return out
-
let so that the sensor well protrudes into the heat exchanger tube. The sensor monitoring the
heating of the DHW cylinder by the boiler is installed at a level corresponding to the amount of
domestic hot water required during the heating season. The supplied cable fitting acts as strain
relief. Installation below the associated coil or heat exchanger is not permissible under any cir
-
cumstances.
•
Buffer sensor:
The sensor required for the solar thermal system is fitted in the lower section of
the cylinder just above the solar indirect coil using the sensor well supplied. The supplied cable
fitting acts as strain relief. As the reference sensor for the heating system hydraulics, it is recom
-
mended to insert the sensor into the sensor well between the centre and upper third of the buffer
cylinder, or positioned against the cylinder wall underneath the insulation.
•
Pool sensor (swimming pool):
Fit a tee into the suction line immediately on the pool outlet and
insert the sensor with a sensor well. In the process, ensure the material used is corrosion-resist
-
ant. A further option would be to fit the sensor as a contact sensor with appropriate thermal insu
-
lation against ambient influences.
•
Contact sensor:
Use scroll springs, pipe clips, etc. to attach the contact sensor to the respective
line. Ensure the material used is suitable (corrosion, temperature resistance, etc.). Then insulate
the sensor thoroughly so that the pipe temperature is captured accurately and ambient tempera
-
tures cannot falsify the result.
•
DHW sensor:
A rapid reaction to changes in the water volume is extremely important when using
the controller in systems that generate domestic hot water by means of an external heat
exchanger and variable speed pump (freshwater module). Therefore fit the DHW sensor directly
on the heat exchanger outlet. This ultra-quick sensor (special accessory, type MSP) should pro
-
trude into the output with the aid of a tee sealed in with an O-ring. The heat exchanger should be
installed upright with the DHW outlet at the top
•
Radiation sensor:
The parallel collector orientation is important in order to obtain a measure
-
ment that corresponds to the collector position. Consequently it should be secured to the sheet
steel covering or adjacent to the collector on an extension of the mounting rail. To this end, the
sensor casing has a blind hole that can be opened at any time. The sensor is also available as a
wireless version.
