Biddle DF2 Installation, Operating And Maintenance Manual page 35

DF M
ANUAL
PROBLEM
Not all connected units are working
(or only partially).
If several units are connected to
a single control panel:
The units (or part of a unit) are not
responding uniformly to the exter-
nal control (door contact switch or
BMS).
The unit is blowing out cold air.
Installation, Operating And Maintenance Manual version 1.0 (16-08-2023)
POSSIBLE CAUSE
The control panel is not communi-
cating with one or more connected
units (or with one of the control
circuit boarda in a dual-control cir-
cuit board unit).
The master unit (or the master
control circuit board in a dual-con-
trol circuit board unit) has not been
configured properly.
The contact on the external control
input is open.
For water-heated units:
The unit is not being supplied any
hot water.
SOLUTION
1. Check that power is supplied to
all connected units.
2. Check the control cables:
• are they connected and free
from breaks?
• are they stretched out or
rolled up neatly? (folded double
before being rolled up)
• are they shielded from
magnetic fields?
3. Check the control circuit board's
fuses in each connected unit.
4. Check wiring between
Connectors and and the
E H
control circuit board(s).
Check whether the unit to which
the external control has been con-
nected has been configured as the
master.
For dual-control circuit board
units:
Check whether the control circuit
board on the connection side has
been configured as the master.
Check the input bridges on the
units to which no external controls
have been connected.
For dual-control circuit board
units:
Check the input bridge on the sec-
ondary control circuit board.
1. Check the central heating sys-
tem.
2. Check whether the valve is
allowing hot water to pass.
3. Check valve drive and inlet tem-
perature sensor wiring and con-
nectors.
4. Take the drive from the valve
and check the interior for
mechanical operation and
defects.
en
E
RRORS
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