Good To Know; Integrated Weather Dependet Function (Wdc) - Heat Curve; Boiler Frost Protection; Air Purging In Central Heating Mode - Buderus Logamax GB062-24 KDE H V2 Service Manual

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Good to know

7.1 Integrated Weather Dependet
Function (WDC) - Heat curve
Weather dependet function (WDC) can activated via
service funtion 1.P.0.
Following parameter A, B and S can be adjustet.
Fig. 29 Heating curve
A End point (at the outside temperature – 10 °C)
Adjustment via service function : 1.P.2
AT Outside temperature
B Base point (at the outside temperature + 20 °C)
Adjustment via service function : 1.P.1
max Maximum flow temperature
pA Flow temperature at the end point of the heating curve
pB Flow temperature at the foot point of the heating curve
S Automatic heating switch-off (summer mode)
Adjustment via service function : 1.P.0
VT Supply temperature
7.2

Boiler Frost protection

The device frost protection function switches the burner and
heating pump on when the temperature in the installation
room (at temperature sensor for heating low) falls below 5
This prevents the boiler freezing.
Fig. 30 Boiler frost protection
7.3

Air purging in central heating mode

Service function : 1.2.C (Factory setting =1).
When the service function 1.2.C is 1 (active), then this
function is active at first power on. The duration for this
function is 2 minutes. No central heating or siphon filling
active when this function is enabled. When DHW
(Domestic hot Water) requested, this mode interrupt,
Logamax PLus GB062
but goes on after DHW request. Pump is switching on
and off every 20 seconds.
Fig. 31 Air purging
7.4

Air Pressure Switch (APS)

Th purpose of using an APS is to detect a flue blockage, if it
happens and safety shut down the burner. APS is physically
connected in serial with safety thermostat (STB).
Fig. 32 Air Pressure Switch (APS)
0 - t1 Burner off, no APS check
t1 heat demand starts (burner on request)
t1 - t2 : Waiting time:
- fan speed setpoint = fan start speed
- waiting time 2 sec.
C.
°
t2 - t3 : Fan and APS check :
- fan speed setpoint = fan start speed
- APS needs to be checked, if APS is open (high pressure), error
3Y shall be set, aftr 5 min., error shall be reset abd next start
attempt will be executed.
- APS must be closed (low pressure) and fan must reach start-
fanspeed +-3 Hz, if so ignition starts.
- if fan doesn't reach startspeed +-3 hz within 300 sec. error 3C
shall be set, after 5 min., error shall be reset abd next start attempt
will be executed.
t3- t4 : Ignition :
- fan speed setpoint = fan start speed
- ignition starts
- APS is monitored by GFA (in serial to STB), if APS is open, 4C
lockout error is set (GFA). Minimum time is 0.5 sec.
- APS is monitored by GFA (in serial to STB), if APS is close, flame
must be available within safety time of 4 seconds.
- if flame isn't available, next start attempt will be executed after
purge time, after 5th start attempt, 6A lockout error is set (GFA)
t4 Burner on
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Good to know
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