Daikin EKHWP500A [8/24] X product description

2 x Product description

Installation instructions

EKHWP300/500A

Hot water storage tank for air-water heat pumps and solar panels

4PW55928-1

2.2 Brief description

The EKHWP300/500A hot water storage tank is a combination of heat storage tank and instantaneous water heater.

The pressureless storage water serves as heat storage medium. Useful heat is supplied and removed via the spiral corrosion-

resistant heat exchanger, which is made from a corrugated stainless steel pipe (1.4404), and is completely immersed in the

storage tank water. In the heat exchanger for domestic hot water there are approx. 24 litres (19 l for the EKHWP300A) of

domestic water stored at the temperature level of the standby zone.

The cold water which flows in when the hot water is drawn off is first routed to the storage tank at the very bottom of the heat

exchanger, where it cools the lower zone of the storage tank down as much as possible. The standby zone is heated up by the

EKHBRD* air-water heat pump. Water flows through the heat exchanger for storage charging (SL-WT) from top to bottom.

On its way to the top, the domestic water continuously absorbs the heat of the storage tank water. Since the flow direction

makes use of the counter flow principle, and the heat exchanger is shaped like a spiral, there is definite temperature stratification

within the storage tank. As high temperatures can be maintained for a very long time in the upper section of the storage tank, a

high hot water output is achieved even if water is drawn off over a long period of time.

The EKHWP300/500A hot water storage tank can also be heated by solar energy. In the EKHWP500A hot water storage tank,

the solar zone in the lower part of the tank is cooled by the cold water flowing in. Cooling also takes place on the heating side if

the heating return temperature is lower than the temperature of the storage tank water. This means that the solar energy

installation always operates at maximum efficiency and produces the maximum heat yield.

2.3 Advantages

Optimum water hygiene

Low flow or unheated zones on the domestic water side are completely eliminated with the EKHWP300/500A hot water storage

tank. It is impossible for sludge, rust or other sediments to be deposited, as can be the case with other large volume tanks. The

water which is fed into the system first is also discharged first (first in, first out principle).

Low maintenance and corrosion

The EKHWP300/500A hot water storage tank is made of plastic and is completely corrosion free. Sacrificial anodes or similar

anti-corrosion units are not necessary. This means that associated maintenance work, e.g. changing the sacrificial anodes or

cleaning the storage tank, does not need to be carried out. Only the fill level of the storage tank water needs to be checked.

The corrugated stainless steel pipe heat exchangers on the heating and domestic water side are made from high quality stainless

steel (1.4404).

Low scaling

On the storage tank side only one deposition of scale is possible. Consequently all the stainless steel heat exchanger pipes

immersed in the storage tank water remain clean. Thus no lime encrustations, which could constantly degrade the thermal

transfer performance (as with other designs of tank) in the course of operation, can build up.

The thermal and pressure expansion and high flow rates in the domestic water heat exchanger release any possible scale deposits,

which are then flushed away.

Economical operation

The full area heat insulation of the storage tank ensures very low heat losses in use and means that the best use is made of the

heat energy being applied.