Operating Instructions; For Users And Contractors; Operation And Control; Equipment Description - Stiebel Eltron WWK 300 Guide D'utilisation Et D'installation

Operating instructions

1 Operation and control

The WWK 300 domestic hot water (DHW) heat
pump from STIEBEL ELTRON is an automatic
DHW heater offering a capacity of approx.
300 l. The required DHW temperature can be
preselected.
Your local contractor will install, connect and
commission your WWK. Nevertheless, you
should familiarise yourself with the most
important aspects of this equipment.

1.1 Equipment description

The WWK 300 contains two heat sources
within the cylinder; both heat the water to the
required temperature:
– Heat pump
– Electrical supplementary heater
The WWK 300, with suffix SOL, not only
contains a heat pump and an electrical
supplementary heater, but also a heat
exchanger permanently fitted inside the
cylinder, which can be supplied with energy
from a boiler or solar heating system.
The WWK 300 extracts energy from the air
which can be utilised to heat the water
contained inside the cylinder. This energy
extraction leads to a cooling of the installation
room by approx. 1-3 °C. The WWK can also
be operated with a connection to an air duct.
However, such air channels must not be
smaller than Ø 200 mm; their length should
not exceed a maximum of approx. 4 m.
The WWK 300 also extracts moisture from the
air, which turns into condensate and must be
drained off. A hose connection is provided for
that purpose.
Additionally Description
PK 10 Condensate pump
Air channel For connection to air hoses /
adaptor channels 200 mm dia. (cir-
cular)

1.2 Correct operation

The appliance is intended for domestic use, i.e.
it can be used safely by untrained persons. The
appliance can also be used in a non-domestic
environment, e.g. in a small business, as long
as it is used in the same way.
This DHW heat pump is designed to extract
energy from the air inside the equipment
installation room or from a room, to the
ambient air of which it is connected, via air
ducts. With that energy it heats domestic hot
water (DHW).

1.3 Incorrect operation

Never
– use greasy exhaust air
– heat liquids other than potable water
– install the equipment
a) outside
b) in rooms at risk from frost

for users and contractors

c) in rooms at risk from dust, gases
or vapours liable to explode
– operate the equipment with an empty
cylinder
– operate the integral heat exchanger
inside the equipment cylinder with
liquids other than heating water.

1.4 Description of functions

1.4.1 Heat pump operation
This is the standard operating mode, to which
the limits of scope of the heat pump apply
(see: specification). To heat the cylinder
content of approx. 300 litres of water to 55 °C,
the WWK 300 (to EN 255 part 3) requires:
ϑ ϑ
H
Space rel Cold water
6 °C 70 % 15 °C
15 °C 70 % 15 °C
35 °C 47 % 15 °C
The water inside the cylinder will be heated to
55 °C by the electrical supplementary heater,
which is controlled by the programmable
time switch, subject to the heating period
being long enough. This enables the option
of making greater mixing water volumes
available at certain times. At all other times,
the water will be heated to the temperature
selected on the controller (see page 4, Fig. 1,
item 3).
If the heat pump was manually swit-
!
ched OFF and ON again after a power
failure, the compressor will only
re-start (after approx. 15 minutes) when the
pressure inside the refrigerant circuit has
normalised again.
Minimum runtime and minimum OFF time
When operating with external swit-
!
ching devices that can interrupt the
power supply to the appliance, such as time
switches, energy management systems or
domestic automation systems, observe the
following conditions:
-The minimum runtime is 60 minutes.
-The minimum OFF time following a shut-
down is 20 minutes.
-The appliance should not be switched ON/
OFF more than 10 times per day.
-The external switching device must have
a minimum breaking capacity of 240 V~ /
16 A / AC3.
1.4.2 Electrical supplementary heater
You can accelerate the heating-up process
with the electrical supplementary heater, if the
DHW demand increases or if the WWK 300 has
previously been switched OFF and you require
hot water as quickly as possible. For reasons
of saving energy, the electrical supplementary
heater only heats the top third of the cylinder
capacity (approx. 100 litres). This takes approx.
2 hours.
In SOL versions, approx. 50 litres are heated
up due to the flange being positioned higher
up on the cylinder.
The electrical supplementary heater is
switched ON when the actual temperature falls
below 58 °C and is switched OFF when 65 °C
are exceeded.
Press the push button only once if you want to
activate the electrical supplementary heater
only to cover a peak demand.
1.4.3 Boiler operation via heat exchanger
(only for SOL version)
A heat exchanger, which is generally
connected to a central heating system, is
integrated into the cylinder. Subject to the
τ
COP(t)
Heat-up
heating water flow temperature, the entire
11.5 h 3.3
cylinder capacity should be heated up by the
heat exchanger in between 3 and 4 hours.
9.0 h 4.2
6.4 h 5.2
1.5 Operation outside the limits of use below
6 °C to 4 °C
Subject to the relative humidity and the
DHW temperature inside the cylinder, the
evaporator begins to ice up below a room
temperature of 6 °C. When the evaporator
is covered in hoarfrost, the frost stat N2 (see
wiring diagram) shuts down the compressor,
whilst the fan continues to operate, thereby
defrosting the compressor. The compressor
starts again automatically after the defrosting
process has been completed, and the heat
pump operation continues.
The minimum temperature required for the
heat pump operation is +4 °C. The evaporator
is defrosted upon demand at operating
temperatures between +4 and
+6 °C. This increases the heat-up time.
Room temperature higher than 35 °C
The heat pump will be switched OFF by safety
equipment at room temperatures above
approx. 35 °C. The heat pump will be re-
started automatically after a brief cooling
down period. The heat pump will be switched
OFF again if the room temperature is still
higher than 35 °C.
Take appropriate steps to prevent
!
the ambient temperature rising
above 35 °C.

1.6 Maintenance and cleaning

The WWK 300 is largely maintenance free.
Maintenance must only be carried out by
qualified contractors.
Have the protective anode checked regularly.
Your contractor, who will be familiar with
your local water quality, will advise you of the
optimum timing for such maintenance. The
first inspection of the protective anode is due
after two years.
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