The valves on the door closer help control the speed at which the door is opening or closing. Let me explain the 4 most popular valves. This is not to be confused with the strength of the door closer – referred to as EN2 through to EN6.
Closing Speed – The closing speed is adjustable and is generally set to 5 seconds closing time, from 180 degrees to 15 degrees. However if you have Delayed Action this will take control of 180 degrees to 70 degrees.
Latch Speed – can be adjusted to Softclose® the last 15 degrees of closing.
Delayed Action – is used to provide a delayed close which helps to assist the passage of trolleys, wheel chair users, pushchairs, prams & elderly or less-abled people. This can be set from anywhere between 180-70 degrees for a maximum time of 25 seconds for fire doors.
Back Check – provides a cushioning effect for when the door is forcibly thrown open but does not serve as a substitute for a door stop. Ideal to help eliminate doors hitting walls or furniture inside a building.
All the valves work on the same principal by turning the valve clockwise will reduce the flow of oil restricting the speed on the opening or closing cycle.
On the closing cycle turning any of the valves clockwise will reduce the speed and anti-clockwise will increase the speed. On the opening cycle for the Back Check valve closing the valve clockwise will increase the amount of back check applied and anti-clockwise for reducing the back check or turning off this function all-together.
Note depending on the model & installation (is it installed in Pull (Fig. 1) or Push (Fig. 66)) this can alter the angle at which the valves take effect from