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4
WHAT TO DO IN CASE OF A FAILURE
4.1
GENERAL
If faults occur, check the following points:
4.1.1 Overheat thermostat
The heaters are equipped with an overheat thermostat,
which shuts off the gas supply if the water temperature
becomes too high. The overheat thermostat remains
engaged until the water temperature falls below the
overheat thermostat shut-off point. The heater must then
be restarted, as the pilot light is also extinguished for
reasons of safety. Remember to set a lower water
temperature on the control thermostat.
4.1.2. Thermal Reflux Safeguard (TRS)
If the TRS shuts the heater down, the heater can be
restarted using the following method:
1. Allow the temperature sensor to cool down until the
temperature falls below the sensor switching
temperature.
2. Operate the RESET button on the TRS by pressing
the small black catch on the thermostat until you feel
a slight click (see diagram 17)
3. The heater restarts and can be operated again.
If the TRS repeatedly shuts down the heater, this
indicates a flue-gas discharge problem. The only
solution is to track down the cause of these problems
(e.g., blocked chimney) and rectify it.
4.1.3. Wrong hot water temperature
1
Check the control thermostat setting.
2
Check that the pilot light is lit. If necessary, relight the
pilot light.
3
Check that there are no leaks or if any taps are open.
4
Check the water temperature just out of the heater to
ensure that low water temperature is not being
caused by cold water being mixed in the pipes.
5. Ask the installer or gas company to check if there is
sufficient gas supply and gas pressure. If the load is
too low this will result in low water temperature
6. Is more hot water being used than was originally
estimated?
7. Inspect the heater for calcium desposition.
4.1.4. Water temperature too high
Check if the control thermostat has been set too high.
Diagram 17 – Resetting the Thermal Reflux System