Water Comfort System · Operating Manual Electronic Temperature Control Unit ELTC-W
BU-091 - 008TCWE
Page 5 of 10
Firmware V0.5.0
Revision 3
Function Description
Normal Operation
The heating cable output is adjusted by a hybrid relay in a frequency ratio
tuned to seconds (period time 10 min.). The frequency ratio is calculated on
the basis of mathematical models of the actual power loss of the pipe and
the actual power of the tape.
With every new start (also after holiday) the heater is activated for 2 hours to
start legionella protection. Before switching on the relay a soft start always
takes place first to reduce the switching current for the relay (20 sec.).
a) Timer Operation
As long as the parameter "Follow Boiler" is not switched to "1", the ELTC-W
works in the timer mode. That means, depending on weekday and time the
stored program is used. A pre-heating period is implemented (Pre-Pow- er)
to have the set temperature reached when the chosen timer operation
starts.
When the temperature is reached, the controller switches to maintenance
temperature.
The following steps are allotted to the timer program accordingly:
0 Output fixed to 0%.
1 The parameter "Economy Mode" is used as set temperature.
2 The parameter "Holding Temp" is used as set temperature.
3 Legionella Protection
→ fixed target temperature is 60° C.
b) Trace Boiler Operation
Is activated by switching parameter "Trace Boiler"on "1". After that the no-
minal value is exclusively determined by the external boiler temperature
sensor. That means, the timer adjustments will be ignored. If this external
sensor measures a temperature higher than the one of parameter "Boiler
Leg. Temp.", the output is set to 100% power to support legionella protection.
If a sensor failure is detected at the boiler temperature sensor, an alarm is
activated and the heating cable output is switched off.
c) Holiday Operation
As soon as for the parameter "Vacation until" a date in the future is entered,
the ELTC-W switches to holiday mode and the power output is deactivated
permanently. When this date is reached (0:00 o'clock) legionella protection
is activated for 2 hours (output set to 100%). After that the timer program is
continued according to the actual date/time.
On the daily date switch (23:59 -> 0:00) the output is operated for a deter-
mined time of 2 hours for legionella bacteria reduction with 100% power. On
the display the remaining time (round up number of days) with a maximum
of 99 days is shown (which means, if the remaining time is under 24 hours
the display shows 1 day).
Frost Protection
By setting the parameter "Activate A.F." the frost protection function is activa-
ted. By a separate sensor input the actual temperature is compared with
the value of the parameter "Switch-On". As soon as the value is reached (or
un- der-run) the output is activated to run the heating tape. As soon as the
value "Switch-On" + "Hysteresis" is exceeded, the output is switched off.
To avoid fast switching cycles a minimum standstill period of 60 seconds is
implemented (that means, after each switch-off of the relay, the re-switch-on
is blocked for 60 seconds). If a sensor failure occurs, the alarm relay is set
and the output is (permanently) switched-off.
Maximum Operation
If level 3 within the timer programming is chosen, the target temperature of
60° C is assumed. When the temperature is reached, the controller switches
to cyclic operation to maintain the temperature.
Operation Types (Modes)
Standard Mode
....................... The heating power is regulated to reach
the set maintenance temperature
Eco-Mode
............................... The heating power is regulated to reach
the set power saving temperature
Standby mode
............................... The heating power is shut down to 0
Pmax Mode
..........................The heating power is regulated to maintain
60°C for legionella bacteria prevention
Pre-Heating-Up
........................... The calculated time until reaching the
next desired value level
Trace Boiler Function
................The timer mode is deactivated and the
boiler temperature is used as desired value
Holiday Mode
..... allows to choose a deactivation period for the heating
Failure / Status Reports
no heating tape ............................ no heating tape found or load current less
than 0.2A; Heating tape
possibly too short (<6m),
not connected, line
interruption or defective
no time ......................................................................no timer settings made,
possibly the controller was switched off for longer time,
over temperature .............................................. inner case temperature >60°
relay defect .............................................. short-circuit of heating tape output
internal failure .......................................restart controller, if failure still occurs
contact eltherm GmbH
F.P.Sensor................frost protection sensor defect / breakage / short-circuit
Boiler ...................................... boiler sensor defect / breakage / short-circuit
>Holiday ..........................Controller is in holiday mode for xx days (xx days)
