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Twin Fans

12 products

Twin fans have two fans in one insulated casing, set up as run and standby, so ventilation carries on if one motor stops. They are used where extract must not fail, such as commercial toilets, plant rooms and other critical supply or extract systems. We stock the Systemair KVK Duo with AC motors from 125mm to 315mm, the KVK Duo EC from 150mm to 630mm, and the KV DUO 315 EC, all in fully insulated AluZinc casings suitable for outdoor and roof installation. Use the buttons below to filter, or for help choosing, email hello@efans.co.uk or call 0161 399 3825.

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Frequently asked questions

What is a twin fan?

A twin fan, also called a run and standby fan, has two fan and motor sets in one casing. One fan runs while the other stands by. If the duty fan fails, the standby fan takes over, so the system keeps running while the failed motor is repaired.

How does the changeover work?

The changeover between the two fans is handled by a run and standby controller or by the building controls, which also allow the fans to be alternated so both share the running hours. Check the datasheet for the model you are looking at, or ask us and we will advise on the controls.

AC or EC twin fan?

The AC KVK Duo models are the lower cost option. The EC models use less energy, run quieter at reduced speed and are speed controlled through a 0-10V signal. Use the buttons above the products to filter by motor.

Single phase or three phase?

The KVK Duo AC models, the KVK Duo EC models up to 400mm and the KV DUO 315 EC run on a single phase 230V supply. The KVK Duo 500 EC and 630 EC are three phase.

Can twin fans be installed outside?

Yes. The KVK Duo and KV DUO have fully insulated AluZinc casings and are suitable for outdoor and roof installation as standard. They can be installed in any position.

What air can a twin fan handle?

Clean or contaminated air at temperatures up to 60°C. They are not suitable for greasy kitchen extract or hot process air: see our high temperature fans for those.

AC EC Single Phase Three Phase

Showing 1 - 12 of 12 products

Systemair KVK 125 Duo Twin Fan duct fan with 125mm diameter, shown in the image.

Systemair KVK 125 Duo Twin Fan duct fan with 125mm diameter, shown in the image.

Product data sheet

In stock

Next day delivery
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Systemair

Systemair KVK 125 Duo Twin Fan - 125mm

1 Phase
AC Motor
Up to 190 m³/h
Speed Controllable

In stock

Next day delivery available

£804.99

Systemair KVK 160 Duo twin duct fan, 160mm size, with dual blades for efficient ventilation, shown in the image.

Systemair KVK 160 Duo twin duct fan, 160mm size, with dual blades for efficient ventilation, shown in the image.

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair KVK 160 Duo Twin Fan - 160mm

1 Phase
AC Motor
Up to 380 m³/h
Speed Controllable

In stock

Next day delivery available

£920.99

Systemair KVK 200 Duo twin duct fan with 200mm diameter, featuring two inline fans with metal casing and electrical connections.

Systemair KVK 200 Duo twin duct fan with 200mm diameter, featuring two inline fans with metal casing and electrical connections.

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair KVK 200 Duo Twin Fan - 200mm

1 Phase
AC Motor
Up to 850 m³/h
Speed Controllable

In stock

Next day delivery available

£1,174.99

Systemair KVK 250 Duo Twin Fan duct fan with 250mm diameter, shown in a close-up view of the twin fan units.

Systemair KVK 250 Duo Twin Fan duct fan with 250mm diameter, shown in a close-up view of the twin fan units.

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair KVK 250 Duo Twin Fan - 250mm

1 Phase
AC Motor
Up to 1060 m³/h
Speed Controllable

In stock

Next day delivery available

£1,314.99

Systemair KVK Duo 150 EC twin duct fan with 150mm diameter, single-phase, energy-efficient ventilation fan for air circulation

Systemair KVK Duo 150 EC twin duct fan with 150mm diameter, single-phase, energy-efficient ventilation fan for air circulation

Product data sheet

In stock

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available

Systemair

Systemair KVK Duo 150 EC Twin Duct Fan Single Phase - 150mm

Up to 548 m³/h
150 mm connection
EC motor

In stock

Next day delivery available

£1,319.99

Systemair KVK Duo 250 EC twin duct fan, 250mm, single phase, ventilation fan for efficient air movement.

Systemair KVK Duo 250 EC twin duct fan, 250mm, single phase, ventilation fan for efficient air movement.

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair KVK Duo 250 EC Twin Duct Fan Single Phase - 250mm

Up to 1152 m³/h
250 mm connection
EC motor

In stock

Next day delivery available

£1,851.99

Systemair KVK 315L Duo Twin Fan duct fan with 315mm diameter, shown installed in ventilation system, designed for efficient airflow.

Systemair KVK 315L Duo Twin Fan duct fan with 315mm diameter, shown installed in ventilation system, designed for efficient airflow.

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair KVK 315L Duo Twin Fan - 315mm

1 Phase
AC Motor
Up to 2315 m³/h
Speed Controllable

In stock

Next day delivery available

£2,088.99

Systemair KVK Duo 315 EC twin duct fan, 315mm single-phase ventilation fan for efficient air movement.

Systemair KVK Duo 315 EC twin duct fan, 315mm single-phase ventilation fan for efficient air movement.

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair KVK Duo 315 EC Twin Duct Fan Single Phase - 315mm

Up to 2008 m³/h
315 mm connection
EC motor

In stock

Next day delivery available

£2,145.99

Systemair KV DUO 315 EC twin duct fan with dual inlets, compact design, and energy-efficient EC motors for ventilation.

Systemair KV DUO 315 EC twin duct fan with dual inlets, compact design, and energy-efficient EC motors for ventilation.

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair KV DUO 315 EC Twin Fan 76833

Up to 2008 m³/h
315 mm connection
EC motor

In stock

Next day delivery available

£2,252.99

Systemair KVK Duo 400 EC twin duct fan with 400mm diameter, single-phase electric ventilation fan for HVAC systems.

Systemair KVK Duo 400 EC twin duct fan with 400mm diameter, single-phase electric ventilation fan for HVAC systems.

Product data sheet

In stock

Next day delivery
available

Systemair

SKU: 449462

Systemair KVK Duo 400 EC Twin Duct Fan Single Phase - 400mm

Up to 4492 m³/h
400 mm connection
EC motor

In stock

Next day delivery available

£3,538.99

Systemair KVK Duo 500 EC twin duct fan, three-phase, 500mm diameter, high-efficiency ventilation fan for HVAC systems.

Systemair KVK Duo 500 EC twin duct fan, three-phase, 500mm diameter, high-efficiency ventilation fan for HVAC systems.

Product data sheet

In stock

Next day delivery
available

Systemair

Systemair KVK Duo 500 EC Twin Duct Fan Three Phase - 500mm

Up to 6422 m³/h
500 mm connection
EC motor

In stock

Next day delivery available

£4,413.99

Systemair KVK Duo 630 EC twin duct fan, three-phase, 630mm diameter, industrial ventilation system, energy-efficient airflow device.

Systemair KVK Duo 630 EC twin duct fan, three-phase, 630mm diameter, industrial ventilation system, energy-efficient airflow device.

Product data sheet

In stock

Next day delivery
available

Systemair

SKU: 448246

Systemair KVK Duo 630 EC Twin Duct Fan Three Phase - 630mm

Up to 13154 m³/h
630 mm connection
EC motor

In stock

Next day delivery available

£5,518.99