Everything you need to know
before you

Everything you need to know
before you

Everything you need to know
before you

buy or install.

buy or install.

buy or install.

Whether you're a homeowner comparing options or an engineer specifying a job, this page covers all verified technical data for the AT Heating Module — 4, 6, 8, and 12 kW.

Whether you're a homeowner comparing options or an engineer specifying a job, this page covers all verified technical data for the AT Heating Module — 4, 6, 8, and 12 kW.

What the numbers actually mean.

You don't need to understand every figure on the spec sheet. Here's what matters for choosing the right model.

You don't need to understand every figure on the spec sheet. Here's what matters for choosing the right model.

Feature title

Output range

Four sizes cover properties from a one-bedroom flat (4 kW) to a large family home up to 180 m² (12 kW). The size you need depends on your floor area and insulation, not the number of radiators.

Feature title

Output range

Four sizes cover properties from a one-bedroom flat (4 kW) to a large family home up to 180 m² (12 kW). The size you need depends on your floor area and insulation, not the number of radiators.

10–85°C

Water temperature range

All models control output water temperature anywhere from 10°C to 85°C, accurate to within 1°C. Underfloor heating typically runs at 35–40°C; radiator systems at 55–75°C.

10–85°C

Water temperature range

All models control output water temperature anywhere from 10°C to 85°C, accurate to within 1°C. Underfloor heating typically runs at 35–40°C; radiator systems at 55–75°C.

2–3 sec

Time to hot water

From cold (around 5°C) to 45°C in 2–3 seconds when installed as an instant water heater. Flow rate exceeds 800 litres per hour at full output.

2–3 sec

Time to hot water

From cold (around 5°C) to 45°C in 2–3 seconds when installed as an instant water heater. Flow rate exceeds 800 litres per hour at full output.

99.69%

Energy efficiency (12 kW)

Verified by EU measurement report. Because there are no wearing parts and the heat transfer surface doesn't scale up, this efficiency doesn't drop over time the way a standard boiler does.

99.69%

Energy efficiency (12 kW)

Verified by EU measurement report. Because there are no wearing parts and the heat transfer surface doesn't scale up, this efficiency doesn't drop over time the way a standard boiler does.

25 yr

Design lifespan

Designed for a 25-year service life. No wearing parts, no scale deposits, no degradation of heating elements. The 20-year replacement warranty is the practical expression of that confidence.

25 yr

Design lifespan

Designed for a 25-year service life. No wearing parts, no scale deposits, no degradation of heating elements. The 20-year replacement warranty is the practical expression of that confidence.

230/400 V

Power supply

The 4 kW and 6 kW models can run on a standard single-phase (230 V) supply or three-phase (400 V). The 8 kW and 12 kW require three-phase only. Your installer will confirm what's available in your property.

230/400 V

Power supply

The 4 kW and 6 kW models can run on a standard single-phase (230 V) supply or three-phase (400 V). The 8 kW and 12 kW require three-phase only. Your installer will confirm what's available in your property.

The recommended floor area figures assume a property insulated to current building standards. Poorly insulated older properties may need a larger model. Your installer should carry out a heat loss calculation before specifying a size.

The recommended floor area figures assume a property insulated to current building standards. Poorly insulated older properties may need a larger model. Your installer should carry out a heat loss calculation before specifying a size.

Find your right size in 60 seconds.

Tell us about your home and we'll recommend the exact AT Heating Module for it.

Tell us about your home and we'll recommend the exact AT Heating Module for it.

Full specification table.

You don't need to understand every figure on the spec sheet. Here's what matters for choosing the right model.

You don't need to understand every figure on the spec sheet. Here's what matters for choosing the right model.

The recommended floor area figures assume a property insulated to current building standards. Poorly insulated older properties may need a larger model. Your installer should carry out a heat loss calculation before specifying a size.

The recommended floor area figures assume a property insulated to current building standards. Poorly insulated older properties may need a larger model. Your installer should carry out a heat loss calculation before specifying a size.

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