Viessmann VITORADIAL 300-T Type VR3, Service Instructions For Contractors

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19
Burner service instructions or separate docu-
mentation by the burner manufacturer
Adjust the maximum oil throughput of the burner to the
rated boiler heating output.
Rated combus-
tion heating out-
put Q
n
Pressure drop on the hot gas
side
kW Pa mbar
97 55 0.55
124 80 0.80
151 120 1.20
Rated combus-
tion heating out-
put Q
n
Pressure drop on the hot gas
side
kW Pa mbar
194 180 1.80
254 240 2.40
323 275 2.75
To protect the system against dew point corrosion,
burner stage 2 (full heating output) must be set to the
rated boiler heating output. It must remain switched on,
even during the summer months (burner stage 2 on
constant standby).
Partial load operation
Set the minimum heating output for the base load
stage according to the conditions of the flue system.
Note that the flue system must be suitable for the low
flue gas temperatures that may occur.
In the case of frequent cycling in standby mode and for
partial loads below 40 % we recommend the following:
■
Insulate the flue gas collector.
■
Install a motorised flue gas damper.
■
Set the minimum runtime for the boiler to 10 minutes.
This extends the service life and reduces running
costs.
Operation with burner load
≥
60 %
The minimum boiler water temperature for oil operation
is 40°C.
To protect the boiler, the minimum heating output at
the base load stage is set to 60 % of rated heating out-
put.
Rated combustion
heating output Q
n
Minimum heating output to
be set (burner stage 1)
kW kW
97 58
124 74
151 91
194 116
254 152
323 194
The base load stage requires a minimum flue gas tem-
perature, the value of which is subject to the design of
the flue system.
Operation with burner load
≥
40 % and < 60 %
The minimum system temperatures (flow/return) are
50/35 °C for oil operation and 60/45 °C for gas opera-
tion.
Commissioning, inspection, maintenance
Adjusting the burner
5692820