Viessmann B2HF - Function sequence and possible faults

48
Supply pressure (flow pressure) Measures
For natural gas For LPG
H E, E+, M L, LL, S, K Lw
Below 13 mbar
(1.3 kPa)
Below
17 mbar
(1.7 kPa)
Below
18 mbar
(1.8 kPa)
Below
16 mbar
(1.6 kPa)
Below
25 mbar
(2.5 kPa)
Do not start the boiler. Notify
your gas supply utility or LPG
supplier.
13 to 33 mbar
(1.3 to
3.3 kPa)
17 to 33 mbar
(1.7 to
3.3 kPa)
18 to 33 mbar
(1.8 to
3.3 kPa)
16 to 33 mbar
(1.6 to
3.3 kPa)
25 to
57.5 mbar
(2.5 to
5.75 kPa)
Start the boiler.
Above 33 mbar
(3.3 kPa)
Above
33 mbar
(3.3 kPa)
Above
33 mbar
(3.3 kPa)
Above
33 mbar
(3.3 kPa)
Above
57.5 mbar
(5.75 kPa)
Install a separate gas pressure
governor upstream of the sys-
tem. Set the pre-charge pres-
sure to 20 mbar (2.0 kPa) for
natural gas and 50 mbar
(5.0 kPa) for LPG. Notify your
gas supply utility or LPG suppli-
er.
Function sequence and possible faults
Display Measure
Control unit issues a heat
demand
No
Increase set value. Ensure
heat transfer.
Yes
Fan starts
No
Fault F.59, F.457 Check connection cables on
fan. Check power supply on
fan.
Yes
Ignition
No
Fault F.359 Check ignition module (con-
trol voltage 230 V across
plugs "X18.1" and "X18.3" on
the burner control units).
Check the gas supply.
Yes
Gas train opens
No
Fault F.357 Check the gas supply pres-
sure.
Yes
Ionisation current builds
No
Fault F.369, F.380 Check distance of ionisation
electrode on burner gauze
assembly.
Purge the gas line.
Commissioning, inspection, maintenance
Checking the static pressure and supply pressure (cont.)
5593201