Ignition Gas Pressure Adjustment; Max C.h. Power Regulation; Anti-Frost System; Uniform Temperature System - Biasi RIVA COMBI Service Manual

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Third Part
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After the adjustment operations bring the selector
back to the normal position (ON).
gas pressure calibration
O Selector 4
This allows you to select the minimum time that
must pass between two ignitions of the burner in
c.h. function.
30 sec.
6

Ignition Gas Pressure Adjustment

By using the device "J" (Figure 1) marked
"ACC.", it is possible to adjust the gas pressure
at the injectors in the ignition phase.
This pressure is maintained at the injectors until
ignition occurs (ionization signal).
To carry out the adjustment move the function
selector 3 to the OFF position (Figure 8) and use
the adjustment device "J" (ACC).
Adjust the gas pressure at the injectors to the
value indicated in the tables of the
User/Installation manual (Technical information
section, Gas pressures at the burner table).
By rotating the device clockwise the pressure
increases.
Check the regular ignition of the burner by
turning the boiler on and off repeatedly.
After the adjustment operations bring the selector
3 back to the normal position ON in Figure 8.
7

Max C.h. Power Regulation

By using the device J (Figure 1) marked "RISC.",
it is possible to limit the maximum useful output
delivered in c.h. function. This adjustment does
not influence the maximum useful output
delivered in d.h.w. function.
RIVA COMBI SERVICE MANUAL – REV A
ON (1)
OFF (0)
Normal
Figure 8
ON (1)
OFF (0)
3 min.
Figure 9
(edition-0106)
By rotating the device clockwise the pressure
increases.
8

Anti-frost System

With the boiler turned on, the anti-frost control is
always active, which briefly starts the boiler until
shutdown at 35°C (primary circuit), so that the
temperature of the c.h. circuit does not drop
below 5°C.
The request is signalled by the LED
in Figure 1.
If there is no gas, the pump runs continuously to
keep the water from freezing.
This function is also active in standby mode.
9

Uniform Temperature System

This system uniform the temperature of the water
in the d.h.w. storage tank at the end of each
request of the d.h.w. temperature probe NTC,
thus preventing temperature layering in the
storage tank.
It is activated at the end of each NTC probe
request for three minutes.
10

Hydraulic Parts Checking System

With the boiler operating (both in winter function
and in summer function) the hydraulic parts
checking system is always active.
This system makes it possible to maintain the
efficiency of the hydraulic parts (pump and three
way diverter valve) by activating them in case of
long periods of unusing.
It is activated when the boiler is inactive for more
than 24 hours.
A) It turns on the pump for 1 minute
B) It makes commuting the 3-way diverter
valve
11

Advanced Probe Control System

By means of this system, the boiler is able to
work quite well even if there is a problem with the
NTC probes.
The table below summarizes the boiler operation.
Control p.c.b. 11.62
"G"
6-4