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Concealed Door Closer (Transom Overhead) Concealed Door Closer (Transom Overhead) Concealed Door Closer (Transom Overhead) Concealed Door Closer (Transom Overhead) Concealed Door Closer (Transom Overhead) Concealed Door Closer (Transom Overhead)
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51A1 Concealed Transom Door Closer Fixin
51A2 Concealed Transom Door Closer Fixin
51A3 Concealed Overhead Tr
PRO50 Transom Door Closer Fittin
Transom Closer Variable Strength 1

Concealed Door Closer (Transom Overhead)

The concealed overhead transom door closer is designed to be concealed within the transom header bar of the door. It provides controlled closing of a single or double action aluminium door or doors. Features built into the concealed door closer include dual closing speed to allow flexibility in closing; three levels of spring strengths and 90o hold open facility. 

Features Include

  • Dual Closing Speed
  • Adjustable spring strength 
  • Retrofit Replacement Items Available 
  • 3 Year Guarantee

  • Specification
  • Order info
  • Documents
  • FAQs


The closer comes complete with its own fixing pack , 51A4 standard pivot and comprehensive fixing instructions. Various arms and spindle lengths are available on request.

293mm x 90mm

Concealed Thickness

Standard Spindle Length
Also available in 17, 22 and 28mm

Maximum Door Width
Light spring - under 750mm (size 1)
Medium spring - 751mm to 950mm (size 2)
Heavy spring - 951mm to 1150mm (size 3)

Maximum Door Weight
100kg - standard pivot
120kg - heavy duty pivot

Maximum Door Height

Closing Speed Dual
Initial closing speed is factory preset.
Final closing speed is full adjustable after installation.

Stable hydraulic fluid suitable for most climatic conditions and constant lubrication

Built in positive back stop and optional 90˚ hold open position

Adjustable spring strength 

Variable Power
Enables the closer to suit each opening, meaning the door closes correctly while keeping the opening force down to a minimum.

Order info

Side Loading Option (includes 51A2 Arm, 51A4 Pivot & fixings)

DDA-NHO-T1-UDDA compliant - no hold open
510100T1-ULight duty (size 1) - no hold open
510200T1-UMedium duty (size 2) - no hold open
510300T1-UHeavy duty (size 3) - no hold open
510900T1-UVariable strength - no hold open
DDA-HO-T1-UDDA compliant - 90o hold open
510190T1-ULight duty (size 1) - 90o hold open
510290T1-UMedium duty (size 2) - 90o hold open
510390T1-UHeavy duty (size 3) - 90o hold open
510990T1-U Variable strength - 90o hold open** - See note
510400D-T1-UDummy closer

End Loading Option (Includes 51A3 Arm, 51A4 Pivot & fixings)

DDA-NHO-T2-UDDA compliant - no hold open
510100T2-ULight duty (size 1) - no hold open
510200T2-UMedium duty (size 2) - no hold open
510300T2-UHeavy duty (size 3) - no hold open
510900T2-UVariable strength - no hold open
DDA-HO-T2-UDDA compliant - 90o hold open
510190T2-ULight duty (size 1) - 90o hold open
510290T2-UMedium duty (size 2) - 90o hold open
510390T2-UHeavy duty (size 3) - 90o hold open
510990T2-UVariable strength - 90o hold open** - See note
510400DT2-UDummy closer

Short Side Loading Option (Includes 51A1 Arm, 51A4 Pivot & fixings)

DDA-NHO-T3-UDDA compliant - no hold open
510100T3-ULight duty (size 1) - no hold open
510200T3-UMedium duty (size 2) - no hold open
510300T3-UHeavy duty (size 3) - no hold open
510900T3-UVariable strength - no hold open
DDA-HO-T3-UDDA compliant - no hold open
510190T3-ULight duty (size 1) - 90o hold open
510290T3-UMedium duty (size 2) - 90o hold open
510390T13-UHeavy duty (size 3) - 90o hold open
510990T3-UVariable strength - 90o hold open** - See note
510400DT3-UDummy closer


51A1Special top arm assembly - short side load
51A2Side load top arm assembly
51A3End load top assembly - use for round nose stiles
51A4Standard bottom pivot assembly
51A5'F' bracket, closing jamb/header bar bracket including fixings
51A10Heavy duty bottom pivot assembly - maximum weight 120kg
FIX-DUMMY     'F' bracket kit standard
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**Variable: If replacing a standard closer with variable strength the bracket highlighted in blue on the Closer Preparation Details diagram will need to
changed. This is supplied with the variable strength closer.

-     Trade pack quantity for all closer types is 4
-     For 17mm extended spindle change code to X-U i.e. 510190T1X-U
-    For 22mm extended spindle change code to X-U-22 i.e. 510190T1X-U-22
-    For 28mm extended spindle change code to X-U-28 i.e. 510190T1X-U-28




Is there a charge for delivery?

Carriage and packing are included in orders over £250.00. A charge of £10.00 is made on lower value orders to cover carriage, packing and insurance. For deliveries to Ireland please speak to the office for pricing.

What do the transom closers come complete with?

Complete fixing kit, bottom pivot assembly and top arm and channel.

What is the maximum weight the 51A10 heavy duty pivot assembly will take?

Up to a maximum weight of 120kg

Do you have any information on CE Marking or CE Marking of Doorsets?

Please refer to our technical section under Standards.

Where can concealed door closers be used? Are they just for residential projects?

Although concealed door closers are often used on domestic doors on flats and apartment main entrance doors, they are also regularly used in commercial settings. A concealed door closer can be used on any door with a light to medium traffic flow. If you’re unsure please contact our sales office on 01202 676262 but generally they can be used in many of the applications where overhead door closers are used.

Can concealed door closers be used on fire doors?

Concealed door closers can be fitted on 30 and 60 minute fire rated doors but the closer
should be CE marked (where applicable) and fire tested in accordance with BS EN1634-1:2000 and BS EN1634-1:1999.  However they must conform to the fire test evidence for the door they are fitted on.

What size door closer to use?

Just like overhead door closers, the size you need depends on the size and weight of the door and where it will be installed – wind force and fire rating may need to be taken into account. Bearing in mind the age and ability of the users, it is important for the door closer to be “suitable and sufficient” for practical everyday use. Fire safety is vital but user safety is very important. If you need any advance on this please do not hesitate to contact our sales office.

How reliable are concealed closers and how do I maintain them once they’re fitted?

Most door closers are all tested to half a million cycles on specially designed test rigs so we are confident in their reliability and we offer a 3 year guarantee.

Concealed door closers require little or no maintenance. Because they are concealed in the door leaf, they are less likely to be damaged, vandalised or stolen so are more likely to give years of trouble free operation than their overhead counterparts.

Why should I choose a concealed door closer above an overhead version?

As a concealed door closer is hidden from sight it looks better! It is reliable and less prone to damage than overheads door closers and concealed door closers are virtually maintenance-free. A quality concealed door closer is extremely competitive against its overhead equivalent.

If I use a concealed door closer does that mean I can't use other hardware on the hinge edge of the door?

It is still possible to use other hardware such as hinges and finger guards even with a concealed door closer in place.


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