Hi guys,

I have the Grundfos CH2-50PC installed bought from Zheilwane.

At first, it was rather quiet and only can hear a hum when the pump is in use. Now, after about 2 weeks moving in, the pump has become rather noisy.

I did empty the water tank a couple of times, once to clean it and again when I installed the water filter.

Any ideas how I can get it back to the quiet hum again?

Think some air may have trapped inside. Or maybe off the pump, let the water run few mins see if it help.

Any screw loose that vibrate against the base?

I have tried switching off the pump and letting the water run for a bit. It doesn't help.

I'll ask my contractor go up have a look when he comes round next time. I don't have a step ladder that is tall enough to climb up into the roof. haha.

BTW, many people say putting copper/steel pipe will have hammer sound, actually i don't notice it in my house. My plumber say a proper installation will have minimal hammer sound.