noisy rads

[poshman]

hi helpers, couple of my rads downstairs are occasionaly noisy eg..
I can here water gushing through the thermostat valve may last for 20 mins then stops or will stop if I turn rad up or down
is it time to change the valves or just one of those things
both rads are alawys hot so no air locks there cheers P M

 

[Armo74]

Is this a recent problem?
The TRV's maybe on the return side of the rad this can sometimes cause problems.