Adjuster arm.Full Description
Door co-ordinators will enable a pair of self-closing doors (i.e. fitted with door closers) with rebated meeting stiles (timber doors) or security astragal (steel doors) to close in the correct sequence automatically, no matter which door leaf is opened first. This is particularly important for pairs of fire/smoke rated doors and pairs of self-latching security doors.
Many other door selectors do not stand the test of time, but the Z304 which is British made has been fully tested to 1,000,000 cycles. It has been fully tested in accordance with BS EN 1158: 1997 + A1: 2002 and is CE marked. Its classification in accordance with Clause 4 is 3-5-5/3-1-1-3. It is easy to fit with full fitting instructions and fixings provided. Please refer to our website for DoP. This product is now also UL Listed.
The standard adjuster arm is 102mm long, but is also available 152mm and 203mm long for thicker or wider doors, and steel doors with astragals both internally and externally. The function of the arm is to drop down under gravity when the doors are opened and “scotch” the second closing leaf until the first closing leaf has closed into the frame.
The unique design feature of the Z304 is the surface rebate catch with patented “toggle”. If the second opening leaf is forced open first, the toggle ensures that the first opening leaf is carried far enough open by the rebate catch to allow the adjuster arm to drop and ensure the correct closing sequence. The toggle at the end of the rebate catch ensures there is always a gap and that the unit works correctly. If the rebate catch is not fitted the unit may still work correctly if the second opening leaf is flung open. However if the second opening leaf is opened slowly (as a Fire Officer would do when inspecting the fire doors, or as a child might do when pushing through the doors) it is imperative that the rebate catch is fitted to avoid the possibility of the leaves binding, or closing out of sequence.
Suitable for timber doors of any width up to 1219mm and all standard thicknesses and rebate sizes. Also suitable for wider steel doors. For applications under difficult or unusual conditions please provide a drawing of your meeting stile and astragal detail, also door thickness and typical width, so we can confirm suitability. Standard stock finishes satin anodised aluminium (SAA) and simulated plated satin stainless steel (SSS). Other finishes including gold anodised, polished chrome effect, brass effect and black anodised aluminium available to order. Other paint finishes are available upon request to standard RAL colours.
Customers often ask us when extended surface rebate catches and/or longer arms should be used. The basic rule of thumb is that a Z304.1/102 selector with a standard surface rebate catch and 102mm arm is suitable for doors weighing up to 100kg, width of leaf between 700mm – 1000mm, leaf thickness between 38mm – 58mm, rebate size 25mm maximum and door closer size 3-5. For all other dimensions that fall outside these it may be necessary to use an extended rebate catch and a longer arm. It can also depend on what other door furniture is on the door and can lead to using a longer arm which has to be determined on site. The extended rebate catch and longer arms are certainly needed when the selector is being installed on doors wider than 1000mm. Furthermore either with a standard rebate or extended rebate catch there may be a scenario where the rebate catch hinders the effective closing of the first closing leaf. If that happens then a longer arm is required.