I just moved in a house (thaistyle;). The watersupply comes from a lake near the house. There is a Hitachi Pressure pump. V-Series hard to read the exakt model. Looks pretty old. When i open the faucet there comes some air out of the faucet, which is very annoying, splashing and noisy. Anybody got an idea why? Is the pump not good or the plumbing?

sid

I would suspect an air leak on the suction side of the pump, possible between the pump and the supply. The fact that you are receiving air under pressure indicates the pump is working

I would suspect an air leak on the suction side of the pump, possible between the pump and the supply. The fact that you are receiving air under pressure indicates the pump is working

Look for an airleak on the inlet side - one other possibilty is the mechanical seal is defective and allowing air into the pump.

Ahh btw. there is a opening on the inlet side which looks like its for letting air out. It looks like a "T" lying on the side and has an opening at the top to be opend with a big wrench. Could the air get out there and the problem stop?

Could well be sucking air in through there. try sealing it and see the result

Check to see if there is an additional hose bib(faucet) off the outlet before it gets to the house. If this has the tiniest leak it will cause problems The gurgling does sound like it is more apt to be in the inlet or line going into the inlet. That would make sucking noises & cause the problem.Or a seal problem on the inlet side.

Is it just when you start the pump? Is the pump drawing directly from the lake? Could be some water is draining from the line between use from a leaky foot valve in the lake?