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Circular Fire Damper

FD-C Fire Damper – 250mm

A single-blade circular fire damper with a 72°C fusible link that closes automatically to stop fire spreading through ductwork, plus an integral manual volume-control facility for balancing airflow. ES-classified and tested to BS EN 1366-2 / BS EN 13501-3.

£131.52

20% VAT added at checkout

In Stock – Available for next day delivery

Order before 3pm today for delivery by Monday 14th September

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SKU: MFD-250-11698
Category: , ,

Description

This circular fire damper is designed to maintain the integrity of fire compartmentation where ductwork passes through walls and floors, stopping the spread of fire through the duct, wall and floor. The single-blade layered design is held open and released by a fusible link with an alloy component that melts at 72°C, allowing the spring mechanism to close the damper automatically in a fire condition. The fusible link is externally replaceable from outside the ductwork, and the damper also incorporates a manual volume-control facility — a settable blade with operating handle and preset positions — for balancing airflow.

Manufactured from galvanised mild steel to BS EN 10346 (DX 51D Z275), with the damper casing conforming to BS EN 1506. The damper body is stitch welded to meet air-tightness test requirements, and the patented blade seal combines layered glass woven sheets with a central intumescent disc to give minimal pressure loss when open and an effective seal when closed. Each unit is supplied with an installation plate that acts as a template for marking fixing positions and allows the damper to be fixed from one side only, with no infill material required.

The damper conforms to the fire damper product standard EN 15650, is tested to BS EN 1366-2 and classified to BS EN 13501-3, achieving an ES classification with reduced smoke leakage characteristics. Tested and certified installation methods are available for blockwork/masonry walls, dry partition walls and concrete floors, achieving ES120 in blockwork/masonry walls and concrete floors and ES90 in dry partition walls. A planned programme of inspection and maintenance should be carried out with reference to BS 9999, and records kept under the Regulatory Reform (Fire Safety) Order.

  • Available nominal diameters: 100mm to 315mm
  • Construction: galvanised mild steel to BS EN 10346 (DX 51D Z275); casing to BS EN 1506
  • Operation: fusible link, alloy melting at 72°C, externally replaceable; with integral manual volume control
  • Fire damper product standard: EN 15650
  • Tested to: BS EN 1366-2; classified to BS EN 13501-3
  • Classification: ES — ES120 (blockwork/masonry walls, concrete floors); ES90 (dry partition walls)
  • Blade leakage: tested to BS EN 1751

Frequently Asked Questions

How does the FD-C circular fire damper operate?

The single-blade layered damper is held open by a fusible link containing an alloy that melts at 72°C. In a fire the link releases and the spring mechanism closes the damper automatically, sealing the duct. The fusible link is externally replaceable from outside the ductwork, so the damper can be reset and re-commissioned after testing without cutting into the duct.

Can it also be used to balance airflow?

Yes. Uniquely for a fire damper, the FD-C incorporates a manual volume-control facility: a settable blade with an operating handle and preset positions. That means it can double as a balancing damper during commissioning, adjusting airflow through the branch it protects, while still providing automatic fire closure via the fusible link.

What fire classification does it achieve?

The FD-C conforms to the fire damper product standard EN 15650, is tested to BS EN 1366-2 and classified to BS EN 13501-3, achieving an ES classification with reduced smoke leakage characteristics. Tested installation methods achieve ES120 in blockwork or masonry walls and concrete floors, and ES90 in dry partition walls.

What sizes and materials are available?

Nominal diameters run from 100mm to 315mm, including 100, 125, 150, 160, 200, 250, 300 and 315mm. The damper is manufactured from galvanised mild steel to BS EN 10346 (DX 51D Z275), with the casing conforming to BS EN 1506 and the body stitch welded to meet air-tightness test requirements.

How is it fixed and maintained?

Each unit is supplied with an installation plate that acts as a template for marking fixing positions and allows the damper to be fixed from one side only, with no infill material required. A planned programme of inspection and maintenance should be carried out with reference to BS 9999, keeping records as required under the Regulatory Reform (Fire Safety) Order.

Should I choose the FD-C or a motorised fire and smoke damper?

The FD-C is fully mechanical — no wiring — and closes thermally at 72°C, making it a simple, economical choice where a fire damper is specified. Where your fire strategy requires closure at the first trace of smoke, for example on escape routes, choose our circular fire and smoke damper instead, which has a spring-return 24V or 230V actuator linked to smoke detection.

Delivery Information

In Stock

Next Day Delivery — order before 3pm Monday to Friday for dispatch the same day.

Delivery Options

ServiceEstimated DeliveryCost
Standard Delivery (UK mainland)Next working day from dispatch£15.95 +VAT (£7.95 for small items)
Free DeliveryNext working day from dispatchFree on orders over £400 ex VAT
Click & CollectCollect from our Leicester branchFree
Scottish Highlands & Islands2-3 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

Six-Week Returns — No Restocking Fees

We want you to buy with confidence. You can return any standard stocked item within six weeks (42 days) of delivery for a full refund — 100% of the item price, no restocking or handling fees. Trade and business customers get exactly the same rights as retail customers. See our Returns Policy for full details.

Return Conditions

  • Items must be unused and in original packaging
  • Custom-made, bespoke or powder-coated items are made to your specification and cannot be returned unless faulty
  • Items must be returned with proof of purchase
  • Return shipping costs are the responsibility of the customer unless the item is faulty

How to Return

  1. Contact our customer service team to arrange a return
  2. Pack the item securely in its original packaging
  3. Include your order number and reason for return
  4. Ship the item to our returns address

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

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