UFH actuator fault. Causes?

[littlespark]

What can do this to an actuator? Overvoltage? Wear and tear? Stuck pin on the valve?



This is in the German built kit house I’ve done work in before. The actuator controller is powered separately to the central heating boiler.. each room has a stat, which then opens one or more actuators for that room.
All the actuators have been taken off by the plumber, so all circuits have water flow, and the house is hot.

 

[brianmoooore]

230 volt ones can, and occasionally do, develop shorted turns and then proceed to cook themselves.
This happened to more than one?

 

[littlespark]

One on each manifold both went pop at weekend.
Others have been replaced in the past.

 

[brianmoooore]

Look them upon Google, and see if this is a particularly troublesome make. Some are rated at 220 volt, so in a UK home where the voltage hovers around 250 volt, there could be a significant degree of overloading.
The fitting of these actuators is usually universal, so try a different make.