14 DKDHR
VI.GP.N2.02
Danfoss District Energy
Instructions Water
Heaters
12.0 Akva Lux II GW - Instructions
12.1 General
Variants
PLEASE NOTE that your water heater may look different than the wa-
ter heater shown, as variants with other components may be supplied.
The control function, however, is basically as decribed below.
Maintenance and setting
The cover can be removed without using tools. For separation and
cleaning of plate heat exchanger see page 18.
12.2 Description
The water heater is based on a gasketed stainless steel plate heat ex-
changer. The domestic hot water is prepared in a heat exchanger based
on the flow principle and the temperature is controlled by a combined
hydraulic and thermostatic self-acting controller PTC2+P controller with
integrated differential pressure controller, which blocks the flow of pri-
mary and secondary side flow through the heat exchanger immediately
after completion of the tapping process.
12.3 DHW temperature control
Danfoss PTC2+P controller (1) for DHW. The DHW temperature is adjusted
by turning the lever towards “+” (warmer) or “-” (colder).
Start by turning the handle
clockwise
- until stop /until the handle can
not be turned anymore. Then turn the handle
counter-clockwise
until
the temperature of the tap water is approx. 48 ° C at normal use (7-8 l/
min). The temperature should never exceed 55 ° C to avoid lime scale
precipitation.
12.4 By-pass or circulation thermostat
Bypass thermostat (default).
As a standard the Akva Lux II GW is equipped with a bypass thermostat,
Danfoss FJVR (2), which ensures that hot water is produced immedi-
ately, when tapping starts. It is recommended to set the thermostat
in pos.3. If the water temperature rises too slowly it can be necessary
to set the thermostat at higher value.
Alternatively a DHW circulation system must be installed.
Circulation thermostat / control change to circulation.
If the water heater is connected to the DHW recirculation system in the
building, the FJVR thermostat (3) will function as a circulation thermostat
and control the circulation water temperature, independently of the set
DHW temperature. It is recommended to set the thermostat in pos 3.
For recirculation connection please refer to page 11 and 12.
The photo to the right shows a water heater, on which circulation hose
and capillary tube have been mounted and connected to the domestic
hot water controller, enabling the temperature of the circulating water
to be controlled by the FJVR thermostat.
12.5 Akva Lux II GW with Danfoss AVE
The AVE expansion unit absorbs the thermal expansion of water in the
heat exchanger. A discharge pipe is not necessary.
For mounting of AVE on site the brass bow must be removed and the
AVE with T-piece and non-return valve must be mounted as shown.
The AVE expansion unit must not be applied to systems with domestic
hot water circulation.
For systems with DHW circulation the expansion
unit must be replaced by a safety valve and a discharge pipe, which is
piped directly into the floor drain, must be installed.
2
1
Handle for temperature setting
