ATTACK AS 1000 Storage Tank with One Heat Exchanger (insulation included in price)

Product detailed description

ATTACK Buffer Tank AS 1000 with One Heat Exchanger (insulation included)

ATTACK buffer tanks with a heat exchanger form a comprehensive range of five solutions, which differ from each other in the method of domestic hot water (DHW) preparation and the number of built-in heat exchangers for charging heating water. This choice is exactly what determines how easily and at what cost you can connect the tank to a heat pump, a wood gasification boiler, a gas boiler, or solar collectors:

• AS – tank with one heat exchanger, purely heating accumulation. It has no built-in DHW preparation, and serves exclusively for the accumulation of heating water and hydraulic separation of the heat source (e.g. a heat pump or a gasification boiler) from the heating circuit. Hot water preparation is in this case solved with an external storage tank (e.g. the ATTACK Z series).
• HR – tank with a built-in enamelled DHW storage tank with a volume of 160 l inside the buffer tank body (a "tank in tank" principle). It contains no additional heat exchanger – heating water is fed directly into the buffer tank, so it is best suited to heat sources that do not require hydraulic separation (typically solid fuel boilers with their own circulation pump).
• HRS – the same construction as HR (built-in enamelled DHW storage tank 160 l), supplemented with one additional external heat exchanger for charging heating water. Thanks to this heat exchanger, the HRS is also suitable for heat sources requiring hydraulic separation, for example a heat pump.
• TUV – tank with a stainless steel coil inside, which ensures instantaneous (flow-through) heating of domestic hot water – cold water flows through the coil and is immediately heated, without the need for a separate DHW storage tank. Heating water is fed in directly, without an additional heat exchanger.
• TUVS – a combination of TUV (stainless steel coil for instantaneous DHW heating) and one additional external heat exchanger for charging heating water – the most universal solution in the range, also suitable for heat sources requiring hydraulic separation (heat pump, combination of multiple sources).

ATTACK Buffer Tank AS 1000 with One Heat Exchanger (insulation included) belongs to the ATTACK buffer tank range with a heat exchanger in the 1000-litre volume category. It is the AS – buffer tank with one heat exchanger variant – purely heating accumulation with a single heat exchanger for charging heating water – without built-in domestic hot water preparation. This page describes exactly this specific model, including its technical parameters, recommended heat sources, and the most frequently asked customer questions.

Key Features

• Removable soft insulation 100 mm thick in a durable leatherette (PVC) cover – easily removed and refitted during connection servicing, without the need for permanent disturbance of the tank surface.
• External heat exchanger for charging heating water with an estimated heat exchange surface of approx. 3.0 m², enabling hydraulic separation of the heat source (e.g. a heat pump) from the heating circuit.
• Welded steel body with an anti-corrosion internal coating, designed for a max. operating pressure of 3 bar and a water temperature of up to 95 °C.
• A prepared G 6/4" threaded port for installing an ATTACK TH electric heating element (2 – 6 kW) as a backup or supplementary heat source.
• Multiple ports (approx. 6 in total) for connecting the heat source(s), heating circuits, temperature sensors and venting – exact port layout according to the manufacturer's documentation.
• Compact footprint with a height/diameter ratio optimised for passage through standard doors and staircases during installation into a boiler room or utility room.
• Ability to combine multiple heat sources at the same time (heat pump, wood gasification boiler, solar system, electric element) thanks to multiple connection levels on the tank shell.
• Made in Slovakia, 24-month warranty from commissioning (max. 30 months from dispatch from the factory).

Technical Parameters

Installation Recommendations

Thanks to the removable soft insulation with a thickness of 100 mm and a practical leatherette cover, the tank retains water temperature for a long time even outside the heating season, and servicing the connections through the insulation is easy – the insulation can be removed and refitted at any time without damage. Thanks to its single heat exchanger, the AS tank is best suited especially where it is necessary to hydraulically separate a single heat source (most commonly a heat pump or an ATTACK DPX/SLX wood gasification boiler) from the heating circuit, while hot water preparation is handled separately – for example, with an external indirectly heated storage tank from the ATTACK Z series (e.g. Z200HP, Z300HP, Z200SOL, Z300SOL) connected to the same heat source.

The AS1000K tank is suitable for use with ATTACK heat sources – with ATTACK DPX/SLX wood gasification boilers (which require heating water accumulation due to the combustion process), with heat pumps, as well as with ATTACK EKO/PLQ/KLQ/E/EZ COMBI stationary cast-iron gas boilers, which need an external indirectly heated storage tank for DHW preparation (these boilers do not include a storage tank themselves). We always recommend having the exact sizing of pipe distribution, pumps, and safety fittings assessed by a licensed heating technician according to the project documentation of the specific building.

When installing, allow for sufficient space around the tank for service access to the ports, sensors, and any electric heating element. We recommend installing a safety valve, expansion vessel, and a venting valve at the highest point of the system in accordance with applicable standards for closed heating systems.

How to Correctly Size the Buffer Tank Volume

The buffer tank volume should primarily be based on the heat source output, the heat loss of the heated building, and the mode of operation. For wood gasification boilers (e.g. ATTACK DPX/SLX), a rough guideline of 20 – 40 litres of accumulation per 1 kW of boiler output is usually recommended, so that the boiler can burn out at full output even outside of immediate heat demand in the house. For heat pumps, the volume is more a matter of hydraulic balancing of the circuit and the number of heating zones, and usually a smaller volume than for wood boilers is sufficient. The AS1000K model with a volume of 1000 litres is suitable, as a rough guideline, for a heat source with output in the corresponding range – however, we always recommend having the exact calculation done by a heating technician based on the energy label, or a heat calculation of the specific building, rather than relying solely on a table estimate.

Other Volumes in the Same AS Variant

If a volume of 1000 litres is not exactly what you are looking for, we also offer the same design solution (purely heating accumulation with a single heat exchanger for charging heating water – without built-in domestic hot water preparation) in our e-shop in other volume ranges:

• ATTACK Buffer Tank AS 500 with One Heat Exchanger (insulation included) – 500 l
• ATTACK Buffer Tank AS 800 with One Heat Exchanger (insulation included) – 800 l
• ATTACK Buffer Tank AS 1500 with One Heat Exchanger (insulation included) – 1500 l

A larger volume means a longer accumulation time and fewer charge/discharge cycles per day, which saves the heat source, but also requires more space in the boiler room and a higher purchase price. A smaller volume is, on the other hand, cheaper and more compact, but if undersized, the heat source may cycle on and off more frequently.

Maintenance and Operation

The AS1000K buffer tank requires minimal maintenance – we recommend checking the tightness of all ports and connections, the function of the safety valve, and the condition of the insulation once a year. For tanks with a stainless steel coil (TUV/TUVS), it is advisable to occasionally check the flow rate and, in harder water areas, to consider filtration at the cold water inlet, which extends the coil's service life and maintains stable flow performance. For variants with a built-in storage tank (HR/HRS), we recommend following the usual maintenance principles for DHW storage tanks, including occasional inspection of the anode, if included in the design. The removable insulation allows for quick and safe access for all of these servicing tasks without the need for permanent damage.

Before first commissioning, we recommend having the system filled, vented, and set up by a licensed technician, who will also confirm the commissioning date decisive for the start of the warranty period.

Safety and Standards

The AS1000K tank is designed for operation in closed heating systems and must always be supplemented with a safety valve with the appropriate opening pressure, an expansion vessel with sufficient volume, and a venting valve at the highest point of the circuit. Installation, connection, and initial commissioning may only be carried out by a person with the appropriate authorisation in accordance with applicable legislation and technical standards for pressure vessels and heating systems. Failure to comply with these principles may lead to a limitation or loss of warranty.

Delivery and Installation

We deliver the AS1000K tank to Slovakia by standard transport on pallets; for larger volumes (from approx. 800 l upwards), we recommend checking in advance the passability of doors and corridors along the route to the boiler room – the weight and dimensions in the parameters table are approximate estimates, and we will gladly confirm the exact values for the specific unit before ordering. We recommend entrusting the actual connection to the heat source, electric heating element, and control system to a professional installation company.

Who This Solution Is Suitable For

We recommend the AS1000K tank with a volume of 1000 litres especially for family houses and smaller facilities that want to efficiently accumulate heating water while also handling domestic hot water preparation in the manner typical of the chosen series (AS – buffer tank with one heat exchanger). We recommend consulting the specific choice of volume and variant (AS/HR/HRS/TUV/TUVS) with a heating technician according to the heat loss of the building, the number of people in the household, the chosen heat source(s), and the desired comfort of hot water preparation.

Frequently Asked Questions

What is the difference between the AS1000K tank and other types in the AS/HR/HRS/TUV/TUVS range?
The AS1000K tank offers purely heating accumulation with a single heat exchanger for charging heating water – without built-in domestic hot water preparation. Other types in the range differ mainly in whether they have a built-in DHW storage tank (HR, HRS), a stainless steel coil for instantaneous heating (TUV, TUVS), or no hot water preparation at all (AS), and in how many external heat exchangers for charging heating water they contain (0 or 1).

What volume of the AS1000K tank do I need for an average family household?
The tank with a volume of 1000 litres is intended for households and buildings that need accumulation corresponding roughly to this output and consumption range. We always recommend calculating the exact volume based on the heat loss of the building, the output of the heat source, and the number of people in the household – we are happy to help you choose based on specific input data.

What is the heat exchanger surface for charging heating water?
The AS1000K tank has a heat exchanger with an estimated heat exchange surface of approximately 3.0 m², which, at typical heat source inlet temperatures, is sufficient for efficient charging of the accumulated water volume within a reasonable time. The exact heat exchanger performance depends on the temperature difference and flow rate on the heat source side.

Is the AS1000K tank suitable for a heat pump?
Yes, the tank has an external heat exchanger for charging heating water, which provides the necessary hydraulic separation of the heat pump circuit from the house's heating circuit – a common connection for ATTACK heat pumps as well as those from other manufacturers.

What is the maximum operating pressure and temperature load of the tank?
The buffer section of the tank is designed for a max. operating pressure of 3 bar and a max. water temperature of 95 °C. The heat exchanger/coil circuit can withstand comparable values; you will find the exact maximum parameters in the technical table below and always also in the accompanying documentation supplied with the tank.

How is the AS1000K tank insulated, and can the insulation be removed later for servicing?
The tank is fitted with soft removable insulation with a thickness of 100 mm in a leatherette cover, which is easily removed and refitted using hook-and-loop fasteners/straps without damage – useful when connecting ports, performing servicing, or additionally installing sensors and heating elements.

Can the tank be combined with multiple heat sources at once (e.g. a heat pump and solar)?
Yes, that is one of the main purposes of a buffer tank with a heat exchanger – it allows the combination of multiple heat sources (heat pump, wood gasification boiler, solar system, electric heating element) into a single buffer tank body. We recommend having the exact connection and the number of required ports designed by a heating technician according to the specific combination of sources.

Is it possible to additionally fit an electric heating element?
Yes, the tank has a prepared G 6/4" threaded port for ATTACK TH electric heating elements (e.g. TH100, TH102, TH103, TH107 with an output of 2 – 6 kW), which serve as a backup or supplementary heat source.

Is the price difference between AS, HR, HRS, TUV, and TUVS only due to additional equipment?
Yes, the price difference between the individual variants of the same volume reflects the number of built-in components – a built-in enamelled DHW storage tank (HR/HRS), a stainless steel coil (TUV/TUVS), and/or an additional external heat exchanger (HRS/TUVS compared to HR/TUV). The more functions the tank integrates, the higher the purchase price, but at the same time you do not need to buy and install separate additional devices.

How does ordering and delivery of the AS1000K tank work?
After ordering, we dispatch the tank from the manufacturing warehouse in Slovakia, and we will inform you of the delivery date by email or phone. If interested, we can also recommend compatible accessories (ATTACK TH electric heating elements, circulation pumps, controls) so that you receive a complete functional set in a single order.

Warranty

We provide a warranty period of 24 months from the date of commissioning for the AS1000K buffer tank, but no more than 30 months from the date of dispatch from the factory. If you have any questions about choosing, connecting, or servicing the tank, please do not hesitate to contact our sales department – we are happy to help design the entire set, including the heat source, circulation pumps, and controls.