Heavy Duty Volume Control Damper - Rectangular - Flangefit - Stainless Steel

Heavy Duty Volume Control Damper – Rectangular – Flangefit – Stainless Steel – Extended Spindle

A heavy-duty multi-blade balancing damper for larger, higher-pressure HVAC systems — rated to 20 m/s and 2000 Pa, with aerofoil blades for minimal pressure drop. Made to order, with hand, extended-spindle or 24V/230V actuator control.

Made to order. Please allow 10-12 working days for delivery.

Order before 3pm today for delivery by Tuesday 29th September

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Description

A heavy duty rectangular multi-blade volume control damper for balancing and regulating airflow in larger and higher-duty HVAC ductwork. Of robust construction with an aerodynamic 100mm airfoil blade profile, it is designed for systems involving high air pressures and velocities, offering smooth airflow with minimal pressure drop. The enclosed drive mechanism sits entirely outside the airstream, maximising free area while protecting the linkage from impact damage and airborne contamination.

The damper is rated for a velocity range up to 20 m/s and duct pressures up to 2000 Pa. It is DW144 compliant, achieving case leakage Classes A, B and C, and conforms to Eurovent 2/2 Classes A–C. Closed-blade leakage performance has been tested to EN 1751. On flanged units, side covers enclose the drive linkage to ensure Class C case leakage and to safeguard against contact with the moving mechanism.

Choose Flangefit or Spigotfit connection and a case and blades in galvanised steel or 430-grade stainless steel to suit the application. Control options include hand quadrant control, a factory-fitted extended spindle (19.05mm diameter) for actuation by others, or a factory-fitted 24V or 230V electric actuator. The design allows on-site conversion between manual and motorised control without a conversion kit or special tools.

Every unit is made to order to your exact width × height, manufactured from 1.2mm steel with welded, sealed corners and a standard 130mm deep case. Suggested operating temperature range is +5°C to +70°C.

Type: Heavy duty multi-blade volume control (balancing) damper, 100mm airfoil blades on a 100mm pitch
Connection: Flangefit or Spigotfit
Material: Galvanised steel or 430-grade stainless steel (case and blades)
Control: Hand quadrant, extended spindle (19.05mm dia.), or 24V / 230V electric actuator
Velocity: up to 20 m/s
Duct pressure: up to 2000 Pa
Leakage: DW144 case leakage Classes A, B and C; Eurovent 2/2 Classes A–C; closed-blade leakage tested to EN 1751
Case depth: 130mm standard
Operating temperature: +5°C to +70°C
Sizing: bespoke, made to order (width × height)

Frequently Asked Questions

When should I choose a heavy duty damper over a standard volume control damper?

Choose heavy duty for larger ducts and higher-duty systems: it is rated for air velocities up to 20 m/s and duct pressures up to 2000 Pa, roughly double the standard damper’s 1000 Pa rating. Its aerodynamic 100mm airfoil blades give smooth airflow with minimal pressure drop, and it can be manufactured in much larger single sections than the standard range.

How is the heavy duty damper constructed?

The damper is manufactured from 1.2mm steel with welded, sealed corners and a 130mm deep case as standard. The 100mm airfoil blades sit on a 100mm pitch, and the enclosed drive mechanism is entirely outside the airstream, maximising free area while protecting the linkage from impact and airborne contamination. Case and blades come in galvanised steel or 430-grade stainless steel.

What control options can I have?

Hand quadrant control, a factory-fitted extended spindle (19.05mm diameter) for actuation by others, or a factory-fitted 24V or 230V electric actuator. The design also allows on-site conversion between manual and motorised control without a conversion kit or special tools, so you can motorise a hand-controlled damper later if the system changes.

What leakage standards does it achieve?

The damper is DW144 compliant, achieving case leakage Classes A, B and C, and conforms to Eurovent 2/2 Classes A to C. Closed-blade leakage performance has been tested to EN 1751. On flanged units, side covers enclose the drive linkage to ensure Class C case leakage and guard against contact with the moving mechanism.

Can I order an exact size?

Yes — every heavy duty damper is made to order to your exact width and height. Enter the flange size for Flangefit units or the spigot size for Spigotfit units in the size fields on the product page and the price is calculated instantly. Because these are manufactured to measure, please allow the lead time shown on the product page.

Delivery Information

Made to Order

This item is made to order. Please allow 10-12 working days for delivery.

Delivery Options

Service	Estimated Delivery	Cost
Standard Delivery (UK mainland)	Next working day from dispatch	£15.95 +VAT (£7.95 for small items)
Free Delivery	Next working day from dispatch	Free on orders over £400 ex VAT
Click & Collect	Collect from our Leicester branch	Free
Scottish Highlands & Islands	2-3 working days from dispatch	£36.95 +VAT

Delivery Area

We deliver to all UK mainland addresses. Scottish Highlands and Islands deliveries may take a little longer. We are not currently delivering to Northern Ireland — Click & Collect remains available.

Questions about delivery? Call us on 0116 246 0031 or email sales@alphaair.co.uk

Returns Policy

Made to Order

This item is made to order and therefore not eligible for a return under our returns policy, unless faulty (see below).

Faulty Items

If you receive a faulty or damaged item, please let us know as soon as possible — ideally within 48 hours of delivery, so we can claim against the courier on your behalf. We will arrange a free collection and send a replacement or issue a full refund. This does not affect your statutory rights.

Questions? Contact us at sales@alphaair.co.uk