Onga pump

[jx2mad]

I have a self pressurising onga pump that every now and then won't start when a tap is turned on. I have to go outside and switch the mains off and back on and the pump runs normally again for a few weeks until it does it again. The pump had a pressure bladder not an air tank and has a pressure switch (which I have replaced) to cut motor off when no water flow. Any ideas why it does this? It is not nice to strip off, get into the shower and turn the water on only to find you have none:(:(:(:) Jim

[Grappler]

I use Onga pressure pumps at my place.

The two usual problems I have are the fine orifice in pressure sensing switch gets blocked with sediment, and ants suiciding in the pressure switch contactors

I pull them apart and clean them out

[Jordan]

I hate the way Onga put a tiny hole at the switch. It seemed designed to give trouble at some point. I've fixed pumps by unclogging this hole.
Replacement switches, not sourced from Onga, don't have this added feature. I don't believe there's any benefit from them, even if they arguably have some damping effect.