20
xtra
-
Installation & Servicing
INSTALLATION
23 BASIC CONTROLS DISPLAY
During the operation of the
xtra
, the status of the
appliance can be determined by the display.
1. Normal Operation Mode
The unit will either be in standby or in operation. The first
digit on the display shows the boiler status (see table). The
last 3 digits show the flow temperature.
2. Blocking Mode
The boiler will enter blocking mode under certain fault
conditions. Whilst in blocking mode the burner is switched
off. Once the fault conditions are clear the boiler will
automatically reset itself. In blocking mode the display will
alternate between showing a '9' in digit one, along with the
flow temperature in digits 2, 3 and 4.
9 9 6
Followed by the blocking code 'bxx'. Refer to page 44 for
Blocking Code references.
3. Error Mode
In error mode the display will show the error code.
Refer to page 42 for error codes.
The boiler will enter error mode under certain fault
conditions. The unit will be inoperative until the fault is
rectified. The reset button is used to reset the boiler
control module after an error has occurred.
Self Check and Anti-seize Modes
After switching on the mains power or after a reset, the
boiler performs a selfcheck, i.e. the DHW valve is
energised and the CH pump is switched on for 10
seconds. This cycle repeats itself every 24hrs, as long as
no heat request is given in 24hrs.
Burner on/off switch
With the burner switch set to 'off' the boiler will not
respond to a CH demand. However, it will respond to a
DHW demand and the pump anti-seize and frost
protection modes are still operational any one of which
could cause the boiler to fire. Note. The burner switch is
NOT a mains isolation switch.
CH/DHW Systems
In standby mode pressing and holding the '+' button for 3
seconds turns the CH system on/off.
In standby mode pressing and holding the '-' button for 3
seconds turns the DHW system on/off.
E 3 6
Sequence
Boiler Status
A
DHW valve energised
0
Standby, no heat request
1
Pre-purge, post purge
2
Ignition
3
Burner on in CH mode
4
Burner on in DHW mode
5
Waiting for air pressure switch to open or close
6
Burner off because a set value has been
reached
7
Pump overrun in CH mode
8
Pump overrun in DHW mode
e.g.
A.
Burner switch
B.
Pressure gauge
C.
Display
D.
Reset button
E.
Mode button
F.
Step button
G.
Store button
H.
+ button (to increase
values)
I.
- button (to decrease
values)
0
I
xtra
MODE
STEP
STORE
RESET
+
A
B
C
D
E
F
G
H
I
im8219
MASTER MODULE
CONTROL PANEL
b 1 8
INST
ALLA
TION
