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ATTACK wall-mounted indirect tanks

Wall-mounted tanks for domestic hot water

ATTACK wall-mounted tanks connect to an external heat source to prepare domestic hot water (DHW). The source page lists the OKC, OKCV, OKH, NTR and SOL types; its published technical table contains nine models with capacities from 120 to 195 litres.

120 l

125 OKC/1 m²
125 OKC

125 l

125 OKCV

147 l

160 OKC/1 m²
160 OKC
160 OKCV

148 l

OKC NTR 160

195 l

200 OKC
200 OKCV

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Category: Domestic hot-water tanks

For differentheat sources

Low NOxLow emissions

No electricityOperates without electricity

Enamelledtank surface

Discover ATTACK wall-mounted indirect hot-water tanks

Suitable for external heat sources

Suitable for external heat sources

The indirectly heated wall-mounted tanks OKC, OKCV, OKH, NTR and SOL are available in capacities from 120 to 195 litres. They are designed to connect to biomass boilers, floor-standing boilers or wall-mounted condensing boilers using different energy sources to prepare DHW in residential and non-residential buildings.

Wall-mounted design

A DHW tank connected to an external heat source

ATTACK wall-mounted tanks prepare hot water using an external heat source. The range includes vertical and horizontal models; each type differs in capacity and heat-exchanger specifications.

ATTACK wall-mounted indirect hot-water tanks

ATTACK wall-mounted tank models

Explore the tank models

Find out which heating appliances they are suitable for.

OKC vertical combination water heater

Suitable for wood-fired or gas boilers

The OKC is a quality combination water heater for domestic hot water, designed for wall mounting. It has a ceramic electric heating element and one built-in heat exchanger for connecting an additional heat source. Its anti-corrosion coating resists pitting, so the heater can also be used with hard and chlorinated water.

Ceramic electric heating element
One heat exchanger
Anti-corrosion coating that resists pitting
Low heat loss thanks to high-quality insulation

OKCV horizontal combination water heater

Suitable for wood-fired boilers

Water in the tank is heated by the heat exchanger or by electricity. A ceramic electric element supports a long service life. High-quality insulation helps keep stored DHW warm for longer by reducing heat loss. You can also use off-peak electricity to lower running costs.

Ceramic electric heating element
One heat exchanger
Heating options: electricity or heat exchanger
Anti-corrosion coating resistant to hard and chlorinated water
High-quality insulation helps reduce heat loss and running costs

OKC/1 m² vertical combination tank

Suitable for wood-fired or gas boilers

Get a dependable hot-water supply tailored to your household. The tank can heat DHW using electricity or a boiler, so you can choose the option that suits you. Quality construction, a ceramic electric element and an anti-corrosion coating support a long service life. High-quality insulation keeps water warm for longer, limits heat loss and helps reduce running costs.

Ceramic electric heating element
One heat exchanger
The 1 m² heat-exchanger version is suitable for boilers using different fuels, including condensing boilers
Circulation connection
Anti-corrosion coating resistant to hard and chlorinated water
High-quality insulation helps reduce heat loss and running costs
Electric heating element included

ATTACK OKC NTR/Z indirect tank

Suitable for condensing boilers

The OKC NTR/Z is an indirectly heated tank with one heat exchanger and no electric heating. It provides hot water throughout the year using heat from a gas boiler and can also be connected to a condensing boiler. Its anti-corrosion coating protects against hard and chlorinated water, while high-quality insulation helps minimise heat loss.

Ceramic electric heating element
One heat exchanger
Year-round hot-water preparation using heating water from a gas boiler
Anti-corrosion coating resistant to hard and chlorinated water
High-quality insulation helps reduce heat loss and running costs

Detailed specifications

Technical data

The product page gives a general range of 80–200 l, while its technical table lists actual model capacities of 120–195 l. This table preserves the published values and full model names. The source page includes an incorrect statement about direct heating below the table; it is not reproduced here.

Parameter	Unit	125 OKC/1 m²	125 OKC	125 OKCV	160 OKC/1 m²	160 OKC	160 OKCV	OKC NTR 160	200 OKC	200 OKCV
Capacity	l	120	120	125	147	147	147	148	195	195
Weight without water	kg	64	55	55	71	62	62	73	79	79
Heat-exchanger output	kW	24	9	9	24	9	9	32	9	9
Heat-up time via heat exchanger from 10 °C to 60 °C	min	17	28	28	21	35	35	16	45	45
Heat-exchanger surface area	m²	1.08	0.68	0.68	1.08	0.68	0.68	1.45	0.68	0.68
Electric heating element power	W	2,200	2,200	2,200	2,200	2,200	2,200	—	2,200	2,200