Checking The Temperature - Biasi ActivA Plus Service Manual

14
13
12
11
10
Figure 9.2
1 Connector - ignition electrode.
2 &RQQHFWRU  ÀDPH GHWHFWLRQ HOHFWURGH
3 Connector - controler fan
4 &RQQHFWRU  ÀXH WHPSHUDWXUH SUREH 17&
5 &RQQHFWRU  GKZ WHPSHUDWXUH SUREH 17& GKZ ÀRZ VZLWFK
and external temperature probe (optional)
6 Connector - Primary circuit pressure switch
7 Connector - safety thermostat and c.h. temperature probe
NTC
8 Connector - remote control (optional)
9 &RQQHFWRU  GLVSOD\ DQG IXQFWLRQ FRQWURO  FK  GKZ WHP-
perature adjustment control panel p.c.b.
10 Fuse F1, F2 2A F
11 &RQQHFWRU  HOHFWULF VXSSO\ 0DLQ HOHFWURQLF FRQWUROLJQLWLRQ
p.c.b.
12 Connector - 3way diverter valve
13 Connector - electric supply control panel p.c.b.
14 Connector - gas valve, pump and fan

9.3 Checking the temperature

The Main electronic control/ignition p.c.b. makes it possible to
VHSDUDWHO\ DGMXVW WKH FK ZDWHU ÀRZ WHPSHUDWXUH DQG GKZ RXW-
let temperature.
The temperature of the water is converted into an electric signal
by means of temperature probes.
The user, setting the desired temperature with the control panel
p.c.b. key or
If the power requested is lower than 40% of the maximum power
output then control is achieved by switching ON the burner at
PLQLPXP SRZHU WKHQ VZLWFKLQJ 2)) 212)) IXQFWLRQ  ,I WKH
power requested is higher, then the burner is switched ON at
maximum power and will control by modulating to 40% of the
maximum power output.
During the c.h. operation (Figure 9.3), the signal coming from
the c.h. temperature probe is compared to the signal given by
the control panel through the adjustment made by the user (key
). The result of such a comparison operates the fan
VSHHG WKXV UHJXODWLQJ WKH JDV ÀRZ UDWH DQG FRQVHTXHQWO\ FKDQJ-
ing the useful output of the boiler.
- 22 -
MAIN ELECTRONIC CONTROL/IGNITION P.C.B.
1 2 3 4
9
.
5
6
7
8
Figure 9.3
When the boiler functions in d.h.w. (Figure 9.4), the signal com-
ing from the d.h.w. temperature probe is compared with the sig-
nal given by the control panel through the adjustment made by
the user (key
Figure 9.4
).
90 °C