Boiler Efficiency, Standard Seasonal Efficiency [To Din] And Standby Loss - Bosch UT-L 1 Technical Manual

28 | Technical description
3
FVB [MW/m ]
1,4
1,3
1,2
1,1
1,0
0,9
0,8
0 2000
Fig. 20 Combustion chamber volume load for UNIMAT UT-L boiler, subject to the boiler output — overview 2
FVB Combustion chamber volume load
Q Rated heating output
B
3.5.4 Boiler efficiency, standard seasonal efficiency
[to DIN] and standby loss
Boiler efficiency and standard seasonal efficiency [to
DIN]
The boiler efficiency denotes the ratio of generated
output compared to rated heat input, subject to the
boiler load and system temperature.
η
η
Boiler efficiency
K
Q Generated output in kW
Q Rated heat input in kW
B
The standard seasonal efficiency (to DIN 4702, part 8)
is measured from the partial load efficiency levels at five
fixed points in the relative boiler output ratings. The
values measured for efficiency at partial load subject to
the relative boiler output ratings should be entered
accordingly. The standard seasonal efficiency [to DIN]
for heating operation is calculated from the values
derived in this way using the following equation:
6 720 807 794 (2013/04)
4000 6000 8000
Q
--------- -
=
K
Q
B
10000 12000 14000
η
Standard seasonal efficiency [to DIN]
N
ϕ
Relative boiler output
i
For boiler efficiency and standard seasonal efficiency [to
DIN] for the various sizes of UNIMAT UT-L boilers, see
also Tab. 17 on page 29.
16000 18000 20000
Q
[kW]
K
6 720 803 977-07.1ITL
5
η ----------------------
=
N
5
1

--------- -
η
ϕi
i = 1
UNIMAT