ATTACK AK 2000 Storage Tank (insulation included in price)

Product detailed description

Why a buffer tank determines heating efficiency

ATTACK Buffer Tank AK 2000 (insulation included in price) is a steel accumulation (buffer) tank with a volume of 2000 litres, designed to store hot heating water from any heat source - a wood gasification boiler, heat pump, electric boiler, gas boiler or solar collectors. This is a tank without a built-in heat exchanger (sometimes also referred to as a "hydraulic separator" or "buffer tank"), which serves purely to store heating water - domestic hot water (DHW) heating with this type of tank is solved externally, for example through a storage water heater or a flow module.

The biggest benefit of a buffer tank is seen when combined with a solid fuel gasification boiler, such as ATTACK DPX or ATTACK SLX. These boilers achieve the highest efficiency and cleanest combustion precisely when they burn at full, rated output - that is, when they burn a whole load of wood "in one go" without throttling the air supply. Without a buffer tank, the boiler would often have to operate in a throttled mode (to avoid overheating the system), which leads to worse combustion, higher tar formation and shorter service life of the boiler and chimney. With the ATTACK Buffer Tank AK 2000 (insulation included in price) the boiler burns the fuel at full output at once, and the excess heat is stored in the water reserve in the tank - from where the heating system gradually draws it according to the current needs of the household, even several hours after the boiler has burned out.

The same principle applies to an electric boiler or a heat pump: the 2000 l tank allows the heat source to operate in longer, less frequent cycles instead of constantly switching on and off in short intervals, which extends the service life of the compressor/heating elements and reduces energy consumption. This is a large-volume industrial/commercial buffer tank, intended for larger boiler rooms, agricultural facilities, dryers, guesthouses or apartment buildings with a central heat source, where heat from multiple boilers or from a large-capacity gasification boiler needs to be stored over a longer period.

Key features of the AK2000K tank

• Volume of 2000 litres - designed to provide a sufficient heat reserve between heating cycles at a recommended heat source output of 80 - 100 kW.
• Soft, removable polyester insulation 100 mm thick - significantly reduces heat losses to the surroundings during long-term storage of hot water, while it can be easily unfastened for inspection or servicing of the tank and fittings.
• Outer insulation cover made of leatherette (PVC fabric) in silver-grey - resistant to abrasion and easy to maintain, visually blends into the boiler room interior rather than looking like a "technical" element.
• 6 connection ports distributed around the shell and on the top/bottom of the tank, allowing connection of the heat source, heating circuits, an additional electric heating element (booster heating), venting, draining and temperature sensors.
• Steel shell with corrosion-resistant internal surface treatment, rated for a maximum operating pressure of 3 bar and maximum temperature of 95 °C - a safe margin over typical operating temperatures of heating water (60-80 °C).
• Suitable for vertical installation thanks to feet/base, which at this volume facilitates precise temperature layering (stratification) - warmer water naturally stays at the top, cooler water at the bottom, increasing the usability of the accumulated heat.
• Option of additional installation of an electric heating element (e.g. ATTACK TH100, TH102, TH103 or TH107) directly into one of the tank's ports - suitable as a backup or supplementary heat source outside the heating season or in the event of a failure of the main source.
• Without a built-in heat exchanger - the tank is intended purely for heating water accumulation; if you also need DHW preparation via a built-in heat exchanger, see our range of AS/HR/HRS/TUV/TUVS tanks with a heat exchanger.

Technical parameters

Note: dimensions and weight of the empty tank are approximate estimates corresponding to the given volume; we recommend verifying the exact dimensions before installation (e.g. in case of limited boiler room space or narrow doors/staircase) directly with the seller before ordering.

How to correctly choose the volume of a buffer tank

The most common recommended rule when choosing a buffer tank for a solid fuel gasification boiler is: for every 1 kW of rated boiler output, count on approximately 20 to 25 litres of accumulation volume. This rule is based on the fact that the boiler burns one load of fuel at full output in approximately 1.5 to 3 hours, and the heat from this load needs to be stored somewhere until the heating system gradually consumes it. For a tank with a volume of 2000 litres, this means it is suitable for a heat source with an output of approximately 80 to 100 kW.

If you have, for example, a wood gasification boiler with an output in this range (from the ATTACK range, these are, for example, some models of the DPX or SLX series - both Standard and Profi versions), the tank ATTACK Buffer Tank AK 2000 (insulation included in price) is adequately sized for your system. For a higher boiler output, or if you plan to combine multiple heat sources (e.g. a wood boiler + heat pump, or a boiler + solar collectors), we recommend choosing a larger volume, or connecting multiple tanks in a cascade - so that the accumulation volume corresponds to the sum of the outputs of the connected sources.

With a volume of 2000 l, it also holds true that the larger the tank, the longer it can supply heat even after the boiler has completely burned out - with a well-designed and sufficiently large system, it is common for a family house to be heated for 12 to 24 hours from a single boiler load and one buffer tank, depending on the outdoor temperature, the house's heat losses and the temperature gradient of the heating system (lower temperatures, e.g. with underfloor heating, allow a larger part of the stored heat to be used than high-temperature radiator systems).

It should also not be forgotten that a buffer tank is worthwhile even in combination with automatic heat sources, such as an electric boiler or heat pump - although these sources can modulate output more smoothly than a solid fuel boiler, they still benefit from the tank by reducing the number of switching cycles, which saves the service life of the compressor, circulation pumps and electronics.

Connection, installation and additional heating options

The ATTACK Buffer Tank AK 2000 (insulation included in price) is typically connected as a hydraulically separated buffer element between the heat source and the heating system (radiators, underfloor heating, fan-coil units, etc.) - the heat source charges the tank through one pair of ports, and the heating system draws heat through the other pair, hydraulically separating both circuits so the system works more stably even with fluctuating flow on the source side. The remaining ports (a total of 6 on this tank) are used, for example, to fit a temperature sensor, air vent valve, safety valve, or to connect an additional electric heating element.

The option to fit an electric heating element is a practical solution for periods when you don't want to heat with solid fuel (e.g. outside the main heating season) or as a backup in case of failure of the main source. Our range includes the electric heating elements ATTACK TH100 (2.5 kW), TH102 (4.5 kW), TH103 (6 kW) and TH107 (2 kW), all with their own thermostat and G6/4" thread - compatible with the ports of this buffer tank. We recommend choosing the element's output according to the tank volume and the desired heating speed.

When installing the ATTACK Buffer Tank AK 2000 (insulation included in price), allow for sufficient handling space in the boiler room - given the diameter with insulation of approximately 1400 mm and a height of approximately 2200 mm (both values approximate, see above), it is necessary to verify in advance the passability of doors, stairs and the room itself. We also recommend leaving a free space of at least 300-500 mm around the tank on the side with the connection ports, to ensure comfortable access during servicing, gasket replacement or checking/adding sensors.

We recommend filling the tank only with treated heating water in accordance with the applicable standard (e.g. STN EN 14868 or the boiler manufacturer's recommendation) - hard water with a high mineral content accelerates limescale formation on the internal walls and shortens the service life of the entire system, including the boiler and circulation pumps.

Connection with other heating system components

The ATTACK Buffer Tank AK 2000 (insulation included in price) is just one link in the heating chain. Customers most often combine it with a ATTACK DPX or ATTACK SLX wood gasification boiler (Standard and Profi versions, output range approximately 15-35 kW), where the boiler output should correspond to the recommended range of 80-100 kW stated above. When combined with a heat pump or electric boiler, the tank serves as a hydraulic separator and heat storage that reduces the number of switching cycles of the source. If you also need to prepare domestic hot water, since this particular tank is a version without a heat exchanger, we recommend adding a separate DHW storage water heater to the system (e.g. from the ATTACK Z series - Z100, Z125, Z160, Z200 and others, available in our range), or choosing one of the AS/HR/HRS/TUV/TUVS series models instead of this tank, which have the heat exchanger built directly into the tank.

Maintenance and inspection of the tank during operation

The ATTACK Buffer Tank AK 2000 (insulation included in price) requires minimal but regular maintenance. We recommend checking once a year (for example, before the start of the heating season) the tightness of all 6 connection ports, the condition of the air vent valve and the safety valve of the heating circuit, as well as the overall condition of the outer insulation cover - the leatherette cover in silver-grey is resistant to normal wear, but in the event of mechanical damage (e.g. during moving or handling in the boiler room) we recommend repairing the damaged spot in time to avoid unnecessary heat losses.

Since this is a tank without a built-in heat exchanger, the inside of the tank only comes into contact with treated heating water, not with drinking water - the risk of limescale build-up is thus significantly lower than with DHW storage tanks, but we still recommend once every few years (for example, when the system is shut down) visually inspecting the inside of the tank through an inspection opening, if the model is equipped with one, or at least monitoring the quality and colour of the heating water when draining sediment from the system. Cloudy or rusty water may indicate the need for water treatment or a corrosion check in the system.

During long-term shutdown (e.g. outside the heating season), it is not necessary to drain the tank - on the contrary, leaving water in the system protects the internal surface from corrosion caused by air ingress. If you plan to shut the tank down completely out of operation for a longer period, consult a professional installer about the appropriate preservation procedure.

Frequently Asked Questions

Do I need to buy a heat exchanger for this tank as well?

No, this AK2000K model cannot be additionally fitted with a built-in heat exchanger - it serves purely for the accumulation of heating water. If you need to prepare domestic hot water via a heat exchanger in a single tank, choose from our AS, HR, HRS, TUV or TUVS series.

How large a boiler can I connect to this tank?

For a volume of 2000 litres, we recommend a heat source with an output of approximately 80 to 100 kW, according to the rule of 20-25 litres of accumulation per 1 kW of output. For a more powerful source, it is better to choose a larger volume or connect multiple tanks in a cascade.

Can the tank be used with a heat pump or electric boiler?

Yes, the AK2000K buffer tank works equally well with a heat pump, electric boiler, gas boiler or solar collectors - in each case it reduces the number of switching cycles of the source and balances the differences between heat production and consumption.

Is insulation included in the delivery?

Yes, the tank is supplied including soft, removable polyester insulation with a thickness of 100 mm and an outer cover made of leatherette in silver-grey.

Can I fit an electric heating element in the tank for additional heating?

Yes, the tank has 6 connection ports, one of which can be used to install an electric heating element, for example ATTACK TH100, TH102, TH103 or TH107 with a G6/4" thread.

What is the maximum operating pressure and temperature of the tank?

The tank is rated for a maximum operating pressure of 3 bar and a maximum operating temperature of 95 °C, providing a safe margin over typical operating temperatures of heating water of 60-80 °C.

What are the exact dimensions and weight of the tank?

Approximately, the diameter with insulation is approximately 1400 mm, the height approximately 2200 mm, and the weight of the empty tank approximately 220 kg. These are estimated values corresponding to a volume of 2000 l - we recommend verifying the exact dimensions with the seller before installation in tight spaces.

What is the warranty period for the buffer tank?

We provide a 24-month warranty from commissioning on ATTACK buffer tanks, but a maximum of 30 months from the date of dispatch from the factory.

Warranty and final recommendation

For the ATTACK Buffer Tank AK 2000 (insulation included in price), the manufacturer ATTACK s.r.o. provides a standard warranty of 24 months from commissioning, but no more than 30 months from the date of dispatch from the manufacturing plant. To maintain the warranty, we recommend connecting and commissioning the tank in accordance with the installation instructions and applicable standards for heating technology, using treated heating water and regularly checking the condition of the insulation and the tightness of the connection ports. We are happy to advise you by phone or e-mail when choosing the right tank volume - just provide the type and output of your heat source, and we will recommend the most suitable model from the ATTACK range.