We're in the southern Philippines (no, it's peaceful here). We have a 2" pipe 200ft down to a well-nigh inexhaustible aquifer. The inserted pipe (drop-pipe?) is 3/4", as it feeds a few non-pressure outlets; the pipe to the tank is 1/2". The tank and pump are Speroni (now called Euromatic?), about 14 years old, but seeming to function as well as ever. The pressure switch is about a month old and has PUMPTROL on the outside of the cover and SQUARE D inside. We have drained the tank and no sediment came out. We did a soap-test on the connections and they were good. There is a check-valve at the end of the drop-pipe - it's not a true foot-valve as it has a threaded open end. We replaced this a week ago - the spring on the old one was very weak. The new one is a Claytonmark. The water is clean - there isn't a trace of any sediment in the water nor has there been in 14 years - and we don't even have a filter. The man who installed it says it doesn't need any cleaning, pumping out sand, nor anything. There was no dirt of any sort in the old check-valve when we replaced it.

From the pump, there are outlets in the house. There is also a separate system to the yard outside, for hosepipes and the mini-piggery. This can be shut off by a stop-****. The tank will slowly lose pressure from about 42, then it falls rapidly to 20 and cuts in. It then goes back to 42 and cuts out until the whole thing repeats after about 8-10 minutes. To get the pump to switch on normally, about 1 1/2 - 2 pints of water has to be drawn. When we close the stop-**** to the yard, the problem goes away. There isn't a smidgen of a leak and certainly not enough to lose 1 1/2 pints in 10mins. We have uncovered every single last inch of the buried pipes, checked the hose-outlets for drips etc. Nada. The pig-drinker outlets? There's only six little piggies just now and they don't drink pints at a time - nor do they drink continuously, 24 hours a day. In fact, of course, we switch off the system at night or when not needed. I've scratched my head until I'm bald - I would be grateful if someone could sort it out for us.

There is another problem. Sometimes - maybe once a month or less, sometimes for a day or two at a time - the pump will run on instead of switching off. If we don't notice it, it gets too hot to touch. We switch off for an hour or two and normal service is resumed. I have an idea - but I'm asking, not telling.