Biasi M300V.2025 SM User Manual And Installation Instructions page 81

page 78 and check that the expansion
vessel pressure is not less than 1 bar.
If the pressure is less, see to correct pres-
surisation.
10.9 Cleaning the domestic hot
water exchanger
Descaling the domestic hot water exchang-
er will be valued by an approved Service
Engineer, who will carry out any cleaning
using specific products.
10.10 Checking the flue system
Have the integrity of the flue outlet and air
intake pipe, checked periodically, at least
once a year. For all the above maintenance
operations it is advisable to call an approved
Service Engineer.
10.11 Combustion analysis check
It is recommended that a combustion analy-
sis check is made. Remove the plug as
indicated in Fig. 10.16 and carry out com-
bustion analysis check and adjustment if
necessary as described in the section "Gas
valve - Adjustment - Chimney Sweep Mode"
of the Service manual.
Fig. 10.16
• Make sure that the ambient thermostat is
in the position "call for heat".
• Withdraw an abundant amount of D.H.W.
by opening the taps.
• Activate the "flue sweep function" at maxi-
MAINTENANCE
Flue analysis
points
mum heating power (see "Setting the
boiler flue sweep function" on page 83).
• Check the combustion of the boiler using
the outlets located on the flue tubes (Fig.
10.16) and compare the data measured
with that following.
Model M300V.2025 SM
Nominal heat input
(A) (E)
Nominal efficiency
Combustion efficiency
Air index
Flue gas CO content
2
Flue gas O content
2
Flue gas CO content
Flue gas temperature
Values refer to tests with a an 80 mm double exhaust
split by 1 + 1 m and natural gas G20 and a supply /
return heating temperature of 60°/80°C.
Fig. 10.17
Model M300V.2530 SM
Nominal heat input
(A) (E)
Nominal efficiency
Combustion efficiency
Air index
Flue gas CO content
2
Flue gas O content
2
Flue gas CO content
Flue gas temperature
Values refer to tests with a an 80 mm double exhaust
split by 1 + 1 m and natural gas G20 and a supply /
return heating temperature of 60°/80°C.
Fig. 10.18
kW 21,0
% 98,4
% 98,7
n 1,3
% 8,5 - 9,5
% 4,8
ppm 220
°C 78,0
kW 26,0
% 98,6
% 98,8
n 1,3
% 8,5 - 9,5
% 4,8
ppm 190
°C 78,0
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