I have an old space heater running along the outside-facing walls. It's a very simple heater: it consists of a pipe, a heat sink all along it, and a cover. I don't know what's inside the pipe; most likely water or oil.
When the heater turns on and turns off, it makes very loud clicking sounds in the bedroom -- loud enough to consistently wake up my wife and me. These clicks happen every couple of seconds for several minutes. And considering it heats up and cools down basically every hour, this results in interrupted sleep and anger at the heater.
My best guess is that the metal is ticking when expanding and contracting, but what can be done to reduce the noise? Surely it wasn't ticking like this when it was brand new.
- Reducing how hot it gets. Then it could stay on continuously rather than cycling. But I don't think I have control over this.
- Putting dampening material in the heat sink, if it's the heat sink that's making the noise. But I don't know what material would be safe.