I have an automatic water pump (Hitachi GP Series WT-P 250GP) which pumps water from my tank to my taps when I turn them on. It's less than a year old, but recently, I have noticed it running when there are no water taps on in our house. It sound like the pump is trying to pump air and water instead of water.
I checked the water tank first, and it's full of clean water, with no obstruction in the pipe which goes to the pump.
I removed the plastic cover and unscrewed the cap on top (pictured with my fat finger pointing at it), and there was a hiss of escaping gas. I poured water in the hole - Mrs benbaaa said this was the thing to do - until it was full, then screwed the cap on again. This seemed to fix the problem for a while, but now I get the sound of water and air being pumped again. Any advice?
This is my pump.
This is the cap I unscrewed.
Cheers,
bb