Power Shower Problem

Hi All,
The pump on my power shower is playing up and I was looking for some advice. What happens is that after about 10-15 minutes use (or two successive showers say) the flow suddenly goes very hot, loses all pressure and then stops altogether. The pump seems to have died but then starts to 'twitch' every five seconds or so, which continues even after the tap has been set back to off. The only way to stop it twitching is to turn it off at the plug.
Anyone got any ideas?
Thanks!
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advice.
Water leaking slowly into the motor, or the cold water supplying the pump has dried up.
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advice.
I would check the header tank, as it sounds to me as though it is emptying.
Mine gives the same symptoms when two showers are taken succesively, may I suggest allowing the tank to refill between showers?
Harv
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the
I
why
Maybe air getting into the system (creating an oscillation driven by the pump compressing a bubble of air)?
-- John Stumbles -+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ -+
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I
why
It "twitches" because as the incoming water goes into the header tank, and enough goes down into the pump for it to push some through.
Harv
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may
Would that happen even after the shower has been switched off, which should turn the pump off as well?
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