Danfoss Akva Lux II Fact sheet

Fact sheet

Akva Lux II

Fully insulated instantaneous water heater for low-temperature district heating

district heating

Mieszkaniowy węzeł cieplny do bezpośrednich systemów centralnego ogrzewania

oraz przygotowania ciepłej wody użytkowej.

Application

Akva Lux II is a fully insulated instantaneous water heater featuring high performance. It meets the future energy demands for low energy consumption and very low standby heat losses. It is especially suitable for large villas with for instance several bathrooms or jacuzzi and for the large family, for which an exceptionally large amount of water is required. The Akva Lux II is also very suiable for small apartment houses with 2-4 apartments.

Construction

The Akva Lux II water heater is prefabricated with a brazed, highly efficient Danfoss plate heat exchanger for domestic hot water production, a domestic hot water controller Danfoss PTC2+P, as well as a Danfoss FJVR thermostat for control of the bypass/ circulation temperature. A circulation set and a safety set is available as optional equipment.

Design

The Akva Lux II is designed for wall-mounting and much importance has been assigned to a user-friendly and easily accessible placement of all system components, including the controllers. The Akva Lux II is fully insulated in an EPP insulation box and can be supplied with a white-lacquered cover in modern design.

Bypass (thermostatic circulation)

The water heater is supplied with a thermostatically controlled bypass, which ensures that hot water is produced immediately, when tapping starts.

The bypass temperature is set with due consideration of the best possible DHW comfort and economy.

Domestic hot water recirculation

The water heater is prepared for domestic hot water circulation. If the household piping includes hot water recirculation the water heater must be connected to the hot water recirculation system and a circulation pump and a non-return valve must be mounted on the circulation pipe and a safety valve must be mounted in the DCW inlet. The pump must be installed so that it pumps towards the water heater. Domestic hot water recirculation ensures that hot water is available at the tapping point without waiting time and waste of water. The circulation temperature is set independently of the set DHW temperature. This ensures the best possible DHW comfort, very low standby losses and thus a very good district heating economy.

Heat exchanger for DHW heating

The water heater is based on a brazed, highly efficient plate heat exchanger type XB 06H1 26 or XB 06H-1 40, which is controlled by a thermostatic and pressure controlled DHW controller, Danfoss PTC2+P with integrated differential pressure controller and energy saving function, which ensures that the heat exchanger is cold during standby. After completion of the tapping process, the controller immediately blocks the district heating flow, to avoid standby, so the losses and to protect the heat-

exchanger from the formation of lime scale and growth of bacteria. The heat exchanger

is cold during standby, so the heat loss is very low. The integrated differential pressure controller compensates for variations in supply temperature and varying differential pressure and thereby ensures a constant hot water temperature at all times.

Service and maintenance

The water heater is very service-friendly and easy to install. It is mounted on the wall and as all pipes are placed in pipe bracket distance, it is possible to establish a nice piping.

FEATURES AND BENEFITS

• Prepared for low-temperature district heating

• Fully insulated and very low heat losses

• Cold heat exchanger during standby, - no standby losses

• DHW controller PTC2+P with integrated diﬀerential pressure controller and energy saving function

• Pipes and heat exchanger made of stainless steel, connections with EPDM gaskets.

• Minimized risk of lime scale and bacteria formation

• Capacity: up to 53 kW DHW

www.danfoss.com

403

463

200

145,5

Material

Size

Scale

Projection

General tolerance accuracy

CIRCUIT DIAGRAM  EXAMPLE

DCW

DHW

Design specications:

Nominal pressure (prim/sec.): PN 16 / PN 16 Max. supply temperature: 120 °C DCW static pressure: pmin = 2.0 bar Min. ΔP: See capacity examples Brazing material (HEX): Copper

Weight excl. cover:

XB06H-1 26 = 8 kg XB06H-1 40 = 9 kg

Insulation: EPP λ 0.039

Cover: White-lacquered steel

Dimensions (mm):

Insulated: H 463 × W 306 × D 190 Insulated with cover: H 463 × W 310 × D 210

Connections sizes:

DH, DHW, DCW: G ¾“ ET (ext. thread) Circulation: R ½“ ET (ext. thread)

supply

2. Danfoss, copper brazed plate heat exchanger in stainless steel AISI 316, type XB 06H-1 26 or XB 06H-1 40.

38. Domestic hot water controller Danfoss PTC2+P with energy saving function (= cold heat exchanger during standby).

40. By-pass/circulation thermostat Danfoss FJVR.

----------------------------------------------------------------------------------

DHW circulation: A. Connection of capillary tube from Danfoss FJVR acting as by-pass (standard function). B. Connection of capillary tube from Danfoss FJVR acting as circulation thermostat. C. Connection of circulation hose. Circulation set for control change from bypass to DHW recirculation is not part of the delivery and must be ordered seperately.

For systems with DHW recirculation the water heater must be supplied with circulation pump, non-return valve and safety valve mounted in the cold water supply.

return

Connections:

200

145,5

1. Domestic cold water (DCW)

2. Domestic hot water (DHW)

3. District heating (DH) supply

4. District heating (DH) return

5. Circulation

Code N o’s:

403

463

306

60 80 60

190

Akva Lux II water heater with heat

Insulated* Code no.:

exchanger type:

XB 06H-1 26

XB 06H-1 40

* Akva Lux II is fully insulated and available with out w/o white cover.

w/o cover 004U8243 w. cover 004U8245 w/o cover 004U8244 w. cover 004U8246

Options:

Cover H 410 x W 310 x D 210 mm Circulation set for mounting on site Safety valve set

DHW: CAPACITY EXAMPLES, 10°C / 45°C

capacity

DHW

[kW]

Plate heat

exchanger

Supply flow

primary

[°C]

Return flow

primary

[°C]

DHW

tap load

[l/min]

32.3 XB 06H-1 26 55 21.8 13.16 0.28 840

32.3 XB 06H-1 26 60 18.9 13.16 0.18 680

32.3 XB 06H-1 40 55 19.0 13.16 0.19 770

32.3 XB 06H-1 40 60 17.0 13.16 0.13 650

41.0 XB 06H-1 26 60 20.4 16.86 0.31 900

41.0 XB 06H-1 26 70 16.8 16.86 0.17 670

53.0 XB 06H-1 40 60 19.1 21.84 0.39 1127

53.0 XB 06H-1 40 70 15.7 21.84 0.25 850

Danfoss Redan A/S · District Heating · Omega 7, Søften · DK-8382 Hinnerup · Denmark Tel.: +45 87 43 89 43 · Fax: +45 87 43 89 44 · redan@danfoss.com · www.redan.danfoss.dk

Pressure loss*

primary

[bar]

Flow rate

primary

[l/h]

VL.GP.G3.02