Electrical installer
Installation, use and maintenance manual – K18 Simplygas
35
4
this case the regulation based on climate curve uses the value
provided by the outdoor temperature probe mounted onboard
the appliance.
4.8.3
DHW storage (GHP'') and DHW charging circuit
(GHP') temperature probes
The DHW buffer tank temperature probe (GHP'') is required if the
DHW production service, directly managed by the K18 Simplygas
appliance, is required.
The probe must be fixed in a dedicated thermowell, with a
length suitable to result immersed in water mass, using thermal
paste to ensure a good heat transfer.
In case one of the optional DHW buffer tanks is used (code
OSRB012 or OSRB004), it is recommended to use the thermowell
just above mid height for the GHP'' probe.
Even in case other water buffer tanks are used, place probe GHP''
in an intermediate position, possibly just above mid-height.
Again in the case of DHW production service directly managed
by the K18 Simplygas appliance, if there is also an auxiliary boil-
er, a temperature probe (GHP') must also be installed on the
DHW charging circuit, immediately upstream of the diverter
valve (detail 16 in Figure 3.2
The GHP'' probe must be connected to the AUX PROBE 3 input. If
there is an auxiliary boiler, the GHP' probe must also be connect-
ed to the AUX PROBE 2 input (Figure 4.12
p. 35). In the absence
of an auxiliary boiler, the EXT.T outdoor temperature probe can
be connected to the AUX PROBE 2 input (Figure 4.13
p. 35, see
also Paragraph 4.8.2
p. 34).
Figure 4.11
Connection of temperature probes to K18 appliance for
heating service only
A
Unit terminal block detail
GHP
Water delivery temperature probe NTC 10k Beta 3977 (supplied as
standard with K18 Simplygas unit)
EXT.T
Air temperature probe NTC 10k Beta 3977 (optional OSND007)
AUX
PROBE 2
T2
T2
A
EXT
.T
AUX
PROBE 3
T3
T3
AUX
PROBE 1
T1
T1
GHP
Figure 4.12
Connection of temperature probes to K18 appliance with
DHW directly controlled by the appliance with an auxiliary
boiler
A
Unit terminal block detail
GHP''
NTC 10k Beta 3977 DHW buffer tank probe (optional OSND004)
GHP'
NTC 10k Beta 3977 DHW charging circuit probe (optional OSND004)
GHP
Water delivery temperature probe NTC 10k Beta 3977 (supplied as
standard with K18 Simplygas unit)
AUX
PROBE 2
T2
T2
A
GHP'
AUX
PROBE 3
T3
T3
GHP''
AUX
PROBE 1
T1
T1
GHP
Figure 4.13
Connection of temperature probes to K18 appliance with
DHW directly controlled by the appliance without an aux-
iliary boiler
A
Unit terminal block detail
GHP''
NTC 10k Beta 3977 DHW buffer tank probe (optional OSND004)
EXT.T
Air temperature probe NTC 10k Beta 3977 (optional OSND007)
GHP
Water delivery temperature probe NTC 10k Beta 3977 (supplied as
standard with K18 Simplygas unit)
AUX
PROBE 2
T2
T2
A
EXT
.T
AUX
PROBE 3
T3
T3
GHP''
AUX
PROBE 1
T1
T1
GHP
4.9
HOW TO CONNECT AN AUXILIARY HEAT
GENERATOR
The K18 Simplygas appliance can control an auxiliary heat gen-
erator (typically a boiler) which can be operated either as an
emergency only generator or as an integration (peak) generator.
For further information refer to Paragraph 5.3.6
The auxiliary boiler can be controlled:
▶
By means of a simple ON/OFF request (provided by the ON/
OFF AUX BOILER contact).
▶
By means of a 0-10 V signal (0-10V AUX BOILER) which can
both provide the request signal and communicate the
