Operation - ThermoFlow Hydrex 18kW Montage- Und Betriebsanweisung

DE
3. User manual
Description of the appliance Hydrex/ Elex
The devices with water pressure control (Hydrex 18, 21, 24kW) and those with electronic
control (Elex 18, 21, 24kW) are intended for use in unvented systems, to heat cold water to
DIN 1988 and to supply one or more draw-off points.

Operation

The integrated flow control valve accommodates changes in water pressure and thus main-
tains a fairly constant temperature.
If the selected outflow temperature is not reached when the tap is fully
opened, then the water flow through the device exceeds the capacity
of the device (18, 21 or 24kW). In this case, the flow should be reduced
with the hot water valve. There is a danger of scalding at outflow tem-
peratures exceeding 43°C.
This unit is intended for use with shower heads with a low pressure
loss. Mixer taps and thermostatic mixer taps should be of a design
compatible with devices with flow control.
Fittings for vented systems should not be used!
Suggestion: To ensure that the minimum flow (switch-on flow) of a water-pressure operated
device is reached, the pressure loss (head loss) of the device, fittings, shower head, shower
hose and piping should all be considered when installing the device.
Typical pressure losses at a shower water flow of approx. 10L/min.
• Mixer tap: 0.4 - 0.8bar
• Thermostatic mixer tap: 0.3 - 0.5bar
• Shower head: 0.3 - 1.5bar.
Model Hydrex 18, 21, 24kW
The hydraulically controlled instantaneous water heater heats the water as it is flowing through
the unit. As soon as a hot water tap is turned on, the heating output is switched on automati-
cally after the switch-on quantity is exceeded. The temperature of the hot water is dependent
on the flow rate and temperature of the incoming cold water.
With the power controller you can select one of the two power settings (E = economy, Max.
= nominal power), depending on the flow.
E (Economy): At this setting the device operates at approximately 2/3 power. For the situation
when a small amount or a low water temperature is needed, f.e. for sinks and bidets.
During summer it is advisable to turn the device to the economy setting.
Max. (Full power): At this setting the device operates at full power f.e. for bath and shower.
Model Elex 18, 21, 24kW
The electronically-regulated continuous-flow water heater with automatic performance ad-
justment keeps the outflow temperature constant. This takes place irrespective of the feed
temperature, up to the performance limit. The hot water outflow temperature is infinitely
variable.
22
GB