What is the difference between permeable (weep) and (standard) non-permeable triggers?
'Weep' triggers are equipped with an opening that allows a small amount of liquid to pass through the trigger even when it is not in use. Thanks to this, a small amount of water always escapes through the device.
In contrast, 'standard' triggers are completely closed when not in use. Barring problems with a leaking seal or damaged parts, a properly functioning, leak-proof trigger should never leak fluid, except when the trigger is pulled.
For what purpose should we use a 'weep' trigger?
The purpose of weep triggers is to maintain a certain degree of frost protection. In colder climates, this small, continuous flow protects devices from freezing.
At the same time, these weep triggers also offer a solution to reduce system pressure on the water side. Long-term maintenance of unnecessarily high pressure is unfavorable for high-pressure pumps and other equipment. By reducing the pressure in a controlled manner, we extend their service life. The simplest way to reduce pressure is to drain the liquid through the trigger, which occurs naturally during intended use. If the system is not used for a longer period of time, the excess pressure is reduced through the pressure reducer (unloader) or the standard pressure regulator.
In the case of such systems, the weep triggers primarily play a pressure-regulating role, since through them the liquid always has the opportunity to leave the system, reducing its static pressure. Weep triggers can thus even perform the role of pressure reducer (unloader), although its use for this purpose is not recommended due to its inaccuracy.
When not to use a weep trigger?
In conditions where there is no risk of frost, the use of a weep trigger is unjustified. A leaky trigger causes unnecessary fluid loss, which is very costly. In such circumstances, the installation and use of a pressure reducer (unloader) is definitely recommended to reduce the pressure.
Weep triggers are only used in some self-service car wash systems. In the case of other high-pressure cleaning tasks, there is no need to use this type of trigger due to the specifics of the use of the equipment.