Product Overview & Application Area
The Sunex FISH S2 300 X is a standing solar hot water tank with a nominal capacity of 300 liters for heating and storing domestic hot water. Two independently operating smooth-tube heat exchangers allow the hydraulic integration of two heat sources, for example a solar thermal system and a boiler, a heat pump, or another suitable heat generator.
The tank design is suitable for bivalent hot water systems where renewable heat is utilized and, if needed, supplemented by a second heat source. The ErP storage volume is 278 liters.
Technology & Equipment
The tank body is made of steel S235JR and is enameled on the domestic water side. Two magnesium anodes supplement the corrosion protection. The two smooth-tube heat exchangers are made of steel P235GH and operate hydraulically independently of each other.
The lower heat exchanger has a transfer surface of 1.2 m² and achieves a continuous output of 39 kW under defined test conditions. The upper heat exchanger has 0.9 m² of transfer surface and a continuous output of 31 kW. The actually transferable output depends on the temperatures, flow rates, and operating conditions of the respective system.
The equipment includes an inspection opening, a circulation connection, several thermometer pockets for temperature sensors, a thermometer connection, and connections for an optional electric heating element. The permanently integrated 50 mm PUR rigid foam insulation reduces heat loss to the installation room. The tank achieves energy efficiency class B with a standby heat loss of 51 W.
Everyday Benefits
The separate heat exchangers create a flexible basis for different system concepts. The lower heat exchanger can, for example, transfer solar heat into the tank, while the upper heat exchanger handles reheating via another heat source.
The inspection opening facilitates inspection, cleaning, and maintenance of the tank interior. Multiple sensor positions support temperature detection and control adapted to the system concept.
System Integration & Compatibility
The Sunex FISH S2 300 X is designed for closed domestic hot water systems with two separately connected heat sources. In addition to solar thermal, suitable boilers, wood heating systems, or heat pumps can be integrated. For heat pump systems, the heat exchanger surface, heat transfer capacity, flow rate, and required hot water temperature must match the heat pump used.
Connections with 1 1/2 inches are available for electric auxiliary heating. The electric heating element, safety group, domestic hot water expansion vessel, pumps, controls, and other system components must be selected according to the respective system design.
Technical Data at a Glance
| Storage Type |
Hot water storage tank with two heat exchangers |
| Nominal Capacity |
300 liters |
| Suitable for drinking water |
Yes |
| Storage tank material |
Steel S235JR, enameled |
| Number of heat exchangers |
2 |
| Insulation |
50 mm rigid polyurethane foam |
| Maximum storage temperature |
95 °C |
| Maximum operating pressure of the storage tank |
10 bar |
| Height |
1,461 mm |
| Width and depth |
657 mm |
| Empty weight |
123 kg |
Installation
The storage tank must be installed exclusively upright in a dry and frost-free room on a level, permanently load-bearing surface. The installation location must be able to safely support the weight of the fully filled storage tank including fittings and piping.
Installation, hydraulic connection, and commissioning may only be carried out by appropriately qualified specialist personnel. Sufficient maintenance clearance must be planned for work on the inspection opening, magnesium anodes, and connections.
Notes
A safety valve with a 6 bar response pressure must be installed at the cold water inlet. No shut-off valve may be installed between the safety valve and the storage tank. If the supply pressure exceeds 6 bar, a suitable pressure reducer is also required.
The storage tank must be completely filled with water and vented before the heat exchangers or an optional electric heating element are put into operation. The magnesium anodes, the safety valve, the tightness and the condition of the storage tank must be checked regularly.
Scope of delivery
- Sunex FISH S2 300 X solar hot water storage tank with permanently integrated PUR insulation and grey PVC outer jacket
