I have replaced a whole house pump with a new one as I required a greater pressure to run a second shower. The original pump was 1.1 bar and the new one is 2 bar. The plumbing around the pump has remained pretty much unchanged after the pumps were swapped. The hot water from the pump supplies 2 showers, the hot kitchen tap and the hot cloakroom tap. The only change I made to the pipework was to fit a check valve in the supply pipework to the hot side of the pump. the reason for this is that there is a hot take off to the bathroom sink tap before the pump. when this tap was turned on, the pump would sometimes startup and then "hammer" I.e. go on and off rapidly. The check valve seemed to cure this. The problem with the pump is that when the system is left for several hours and I then turn on either the kitchen or cloakroom taps the pump does not always start. By turning on the shower the pump starts up. I assume that this is because the shower operates both hot and cold sides of the pump. If the hot water is left for upto an hour or so it seems to work fine. I'm not sure what could be causing the problem. My guesses so far are:
Water being sucked down the vent pipe dragging air into the pump.
The check valve not allowing air to return up the vent pipe.
Any ideas?
I can provide photos if that helps?
Water being sucked down the vent pipe dragging air into the pump.
The check valve not allowing air to return up the vent pipe.
Any ideas?
I can provide photos if that helps?
