Malfunctions
Thermo E 200/320
58
14
Malfunctions
Malfunctions are signalised by the operation indicator. During all active
operating phases of the heater, all components, the operating voltage
and functional irregularities are monitored and recorded. A malfunction
causes the heater to terminate its operation by a fault shut-off and to go
into the fault lock-out mode to prevent the heater from an automatic
combustion restart. At the same time the operation indicator begins
immediately to flash after detection of the malfunction with a specific
code depending on the kind of malfunction. If the heater remains ener-
gized, the operation indicator keeps flashing until the heater is freed.
The flash code comprises of a sequence of 5 short flashes depicting the
break and a defined number of long pulses corresponding to the
malfunction number, which are to be counted. After that the cycle starts
with 5 short flashes again and so on.
The meaning of the number of long pulses is shown in the table below.
The
fault lock-out
occurs:
– if combustion was not established during start-up
– Flame interruption
– if the control device itself has failed or peripheral components are
defective
– undervoltage within a defined time period
– extrinsic light
Variants to reset the heater after a fault lock-out:
1. Switch off the main switch (MS) and then turn it on again.
2. Reset the control device, e.g. through disconnecting it from the
power supply.
Additional to the fault lock-out a heater lock-out occurs if safety related
components such as the flame guard and the overheating protection are
affected as well after reaching a counter threshold of repeated malfunc-
tions and flame interruptions. The heater lock-out is saved by the control
device.
Under the following conditions a
heater lock-out
occurs:
– overheat protection/ function has been activated or is defective
– water temperature sensor is defective
– solenoid valve is defective
– flame guard is defective
– repeated malfunctions
– repeated flame interruptions
– flame within the purge cycle 2
– malfunction of the control device
In case of a heater lock-out, the heater is to be maintained and released
by Spheros trained personnel
Before deleting the fault or heater lock-out the failure cause must
be remedied!
Variants to reset the heater after a heater lock-out:
1. Immediately after the malfunction occurs
(within 2 min)
– Keep the heater energized.
– If no purge cycle took place, when for example the malfunction did
occur within the initial cycle, skip the next point.
– Await the purge cycle (Attention: Reading the flash code 8, the purge
cycle takes place without burner motor).
