Abloy · Concealed Closer · Wood-Frame Fire Doors

DC840

Abloy · Made in Finland · Concealed · Fire-Rated

DC840 is Abloy's invisible closer — the body fits into the head of the frame so neither face of the door has any closer hardware to read. We specify DC840 in two places: on CB elevator doors where the surface arm of a DC135 / DC175 would interfere with the cab travel, and on GD wood-frame fire-rated doors where the design intent is a flush plaster head with no visible mechanism. The same cam-action geometry as the DC-series surface closers, just relocated into the frame.

UseCB elevator · GD invisible fire doors

MountConcealed · Inside the frame head

VisibilityInvisible from both faces

Quantity

In the details

The closer that doesn't read.

Concealed body

The closer body lives inside the frame head; only a track and arm cross the gap to the leaf, both of which disappear into the rebate when the door is closed. From either face, no closer is visible.

Cam-action

Same low-opening / high-closing cam profile as DC135 and DC175 — easy to open, positive close. The action is identical to a surface closer; only the location moves.

Fire rating

Certified for wood-frame fire-rated doors when installed per the manufacturer instruction sheet. The full assembly is part of the fire-test chain.

Where we specify it

Two places: CB elevator-cab doors, where a surface arm would foul the cab; and GD wood-frame fire-rated doors where the design calls for an invisible head. Pairs with Simonswerk AN 107-3D-C60 on the matching invisible self-closing leaves.

Technical specifications

Abloy DC840 — full specification

DC840 is a concealed cam-action closer that fits into the frame head and the leaf, leaving both faces clean. Installation requires preparation of both leaf and frame; the certified install procedure is on the Abloy installation-instruction sheet.

Type	Concealed · Frame-head mounted · Cam-action
Strength	EN 2 / 3 / 4
Door width	Up to 950 mm (37.4")
Door weight	Up to 80 kg (176 lb)
Visibility	Concealed — both faces clean
Closing speed	Adjustable · independent latch speed
Backcheck	Available · adjustable
Fire rating	Approved for wood-frame fire doors per install instructions
Frame depth	Min 60 mm rebate required
Standard	EN 1154 · EN 1634-1 (with rated leaf)

Manufacturer datasheet

Full installation guide on Abloy

Abloy publishes the complete DC840 installation instructions — including the wood-frame fire-rated installation procedure — as a PDF on their global site. We mirror the same closer through our specification.

External · Manufacturer · PDF

DC840 Installation Instructions — Abloy

abloy.com · Opens in new tab

Specify this closer

Specify DC840 on your invisible fire doors.

Tell us whether it's a CB elevator door or a GD wood-frame fire door, the leaf width, and the rating. We'll spec the closer and coordinate the frame-head prep before delivery.

Inquire about DC840