Fitting an automatic door closer is important on doors that separate areas where a fire could possibly start from other living areas.
A concealed door closer consists of the spring and chain mechanism in a metal barrel and two metal plates that attach to the frame and the door. The metal barrel that conceals the spring and chain needs to be embedded into the door, whilst the plate attached to the chain is fixed to the frame.
When the door is opened, the chain is pulled out of the barrel and compresses or extends the spring. The spring then causes the door to be pulled closed as it returns to its normal state.
Step 1 – Drilling the hole
Mark the position of the closer on the hinge-edge of the open door. Make sure the mark is in the middle of the door edge. You will need to drill the hole for the closer mechanism with a drill bit that is the same diameter (or as close as possible). Before you start to drill, mark the depth of the closer mechanism on the drill bit using electrical tape so that you know when the hole is deep enough.
Slide the metal barrel into the hole you have drilled so that the screw plate sits flat against the edge of the door. Draw around the screw plate with a pencil and then remove the metal barrel from the hole. Using a sharp woodworking chisel, remove a layer of wood inside the pencil marks so that the screw plate sits flush with the surface of the wood.
Step 2 – Marking the plate position
Slot the metal barrel back into the hole and close the door. Hopefully, the metal screw plate will make a faint mark on the door lining where it touches when the door is closed. You can then use this mark to chisel out a layer of wood for the anchor plate.
If there is no mark left by the screw plate, you can either try transferring the position onto the door lining by eye, or you can try rubbing a pencil lead around the edge of the screw plate, then closing the door to see it that leaves a mark to follow. Transferring the position of the anchor plate by hand isn’t too difficult, but you should take care to make it as accurate as possible.
Step 3 – Attaching the screw plate
Screw through the plate that fixes the barrel to the door using the screws provided or recommended. Make sure it is firmly fixed. Now pull the anchor plate away from the screw plate using pliers. This will expose the chain which attaches the plate to the spring inside the metal barrel. The closer kit should have come with a holding clip which slips onto the chain to stop it retracting back into the cylinder. If not, you can use a thin nail or piece of wire pushed through one of the chain links to hold the chain out.
Step 4 – Fixing the anchor plate
You can now pull the anchor plate around so to that it sits in the recess you chiseled out of the door lining. Drill pilot holes and then screw the anchor plate into place. You may need to chisel out a bit more in the door lining to accommodate the shaped back of the anchor plate.