7
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 being influenced by the ambient temperature.
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 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 fitting (= 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 inte
-
grated smooth tube heat exchangers are used, in the lower third of the exchanger or the
exchanger’s return outlet 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 circumstances
.
•
Buffer sensor
: The sensor required for the solar thermal system is fitted in the lower sec
-
tion 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 recommended to insert the sensor into the sensor well between the cen
-
tre and upper third of the buffer cylinder, or positioned against the cylinder wall under
-
neath the insulation.
•
Pool sensor (swimming pool)
: Fit a tee into the suction line immediately on the pool out
-
let and insert the sensor with a sensor well. In the process, ensure the material used is
corrosion-resistant. A further option would be to fit the sensor as a contact sensor with
appropriate thermal insulation 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 accu
-
rately and ambient temperatures 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 protrude 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
.
