D2CND0 D2CND0 D2TND0
D2TND0 D2TND024A4AA
Wall-mounted condensing boiler
ESIE17-09 / 2017.11
Servicing manual
34
When DHW inlet is supplied by a pipe coming from
solar tank, Solar NTC sensor must be connected to
the boiler and DHW solar function must be activat-
ed. Otherwise, uncomfortable conditions may occur
for the customer.
WARNING
Refer to table below for P10 adjustment:
7.10.4.1 DHW solar function logic
If the solar sensor is connected and solar function is enabled
(P11 =1), boiler checks following two conditions for DHW op
-
eration;
1. DHW se 5K > [Ts DHW]*
[Ts DHW]* : Calculated DHW outlet temperature depending
solar NTC value, actual water flowrate and minimum burner
capacity.
Example: DHW setpoint = 45°C
Solar NTC value = 40°C } [Ts DHW] = 55ºC
Flowrate
= 3lt/min
Since 45 + 5 < 55, boiler does not run. This function aims to
prevent discomfort that may occur due to high DHW tempera
-
ture.
2. Solar NTC value < DHW se P12 “Solar Hysteresis
ON”
example: Solar NTC value 40ºC
P12 value = -3K
In this case, boiler does not operate if DHW setpoint is be
-
low 43°C. Purpose of this function is to prevent unnecessary
burner operation. P12 parameter must be chosen according
to customer preference.
In case of Solar NTC sensor fault, solar function is
deactivated and boiler operates as if normal DHW
operation.
WARNING
7.10.5 Connecting the Appliance to Underfloor Heating
(UFH) System
This boiler can be connected to a well designed underfloor
heating system without needing an additional pump. Always
refer to the performance curve of the pump to check the limits.
i.e. it is possible to connect the boiler to an UFH system up to
15 kW (∆Tflow-return = 10°C, 10 circuits and lenght of the
each circuit is 80 metres) without an additional pump.
When the boiler is connected to an UFH system, the following
parameter changes must certainly be done.
Parameter “Max. flow temperature setpoint (P15)” = 50°C
Parameter “Delta T flow and return pump (P17)” = 10 Kelvin
Parameter “Min. flow temperature setpoint (P19) = 25°C
Please note that these parameter changes are necassary for
smooth running of the system and for the customer comfort.
7.10.6 Weather Compensation
Weather compensation means the operation of the boiler ac
-
cording to outdoor sensor temperature.
Weather compensation is activated if:
1. An outside sensor connected to the boiler (power interrup
-
tion needed).
and
2.The Parameter “heating-slope” (U01) value > ‘0’
Weather compensation is deactivated if,
1. An Opentherm R.T. is connected
or
2. The outdoor sensor value is out of converting range, most
probably due to sensor error.
7 Operation
a
b
2
1
n
X (m)
P10
01
2
02
3
03
4
04
5
05
7
06
8
07
10
08
11
09
12
10
14
11
15
12
17
13
18
14
19
15
21
}
a Solar tank
b X metre
Underfloor heating system
1 Flow collector
2 Return collector
n Each circuit
7.10.4 DHW Solar Function
This is a function that decides whether the boiler should op
-
erate or not in case domestic cold water is fed by a solar tank
which is heated up by solar energy.
Solar sensor must be connected to X1M terminal (refer to title
“Combining the boiler with options”). Solar sensor connection
is automatically detected after power on. Solar sensor value
can be followed from parameter A05 in Info menu.
Solar sensor connection is not enough for DHW solar function
activation, Parameter “DHW solar function activation (P11)”
must also be adjusted to ‘1’.
The burner will be switched On for DHW if DHW solar delay
time (P10 value) is elapsed and both above conditions are
fulfilled.
Burner stops if Solar NTC value > DHW setpoint
