OPERATION
Water heater description
4.
Water heater description
The water heater switches on automatically as soon as a hot water
valve at a tap or other draw-off point is opened. DHX heats water as
it flows through the unit. When the tap is closed, the water heater
switches off automatically.
From the activation flow rate, the electronic control unit regulates
the correct heating output using only the minimum amount of power
necessary, subject to the temperature selected and the current in-
coming cold water temperature.
DHX Trend and DHX Plus are electronically controlled tankless water
heaters, and maintain a consistent outlet temperature. This is irre-
spective of the inlet water temperature, up to the maximum output
of the water heater.
DHX Plus models feature Advance Flow Control
ented by Stiebel Eltron in Germany (patent no. DE 3805441 C2). When
the maximum output of a DHX Plus model is met, rather than deviate
from the setpoint temperature and deliver cooler water, DHX Plus
models use an electronically-controlled motorized valve to slightly
reduce the flow of water only as much as is necessary to maintain
the user-selected temperature. When the demand can again be fully
met, the motorized valve returns to the fully open position, allowing
the full flow rate. This ensures uninterrupted comfort, and hot water
delivered at the desired temperature at all times.
If the water heater is operated with preheated water, and the inlet
temperature exceeds the selected set temperature, the inlet tem-
perature will be displayed on the second row of the screen (DHX
Plus models only) and will flash. The water is not heated further.
DHX models are equipped with functions to permanently limit the
temperature (childproofing).
DHX Plus models feature a backlit display that switches on auto-
matically as soon as water flows through the unit, or if a change is
made at the user interface. The backlight switches off automatically
if no changes are made for 30 seconds, or 5 seconds after hot water
stops being drawn.
DHX Plus models allow the user to save different preset tempera-
tures and apply them quickly.
DHX Plus models also offer a more in-depth 2-line display with
enhanced functions. The DHX Trend has a single-line display and a
more basic user feature set.
Domestic Hot Water (DHW) temperature
The DHW outlet temperature can be variably adjusted from 68–140 °F
(20–60 °C). The selected temperature is displayed.
Heating system
™
The Direct Coil
heating system is comprised of a pressure-tested,
glass-reinforced polyamide heating chamber with a nichrome wire
direct heating coil. It is suitable for hard and soft water areas and
is largely insusceptible to scale build-up. The Direct Coil
system ensures rapid and efficient DHW production.
www.stiebel-eltron-usa.com
5.
5.1
™
, a technology pat-
1 Display
2 Operating LED (flashes when output limit is reached)
3 Control knob
5.1.1 DHX Trend display overview
1
1 Digit display
2 Temperature unit indicator
™
heating
Note
The water heater is equipped with an air detector that
largely prevents damage to the heating system. If, during
operation, air is drawn into the water heater, the water
heater shuts down the heating output for one minute to
protect the heating system.
Settings and displays
DHX Trend user interface
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2
3
2
DHX Trend & DHX Plus |
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