Pressure boosting pump cycles when dishwasher fills

lardconcepts · 2010-07-30T20:19:27+00:00

I bought a Salamander Right Pump RGP80 to replace a pump in this oldhouse of ours, which has ridiculous 15mm pipes all round. Without apump, the toilets, washing machine, dishwasher etc all take 10 minutesto fill.With a pump, we get a wall-washing burst of water from the sink, butat least there's a hope of dispensing with that irksome floater (notin the sink, I hasten to add!).The thing is, about a week after installing it, when the dishwasherfilles the pump cycles on for half a second, then off for 1.5 seconds,and so this goes on for about 2 minutes until the dishwasher is full.Putting my ear to the dishwasher, I can hear a gentle hum of asolonoid and also water still trickling in, so it's not the dishwashercycling it. But, if I turn on the nearby kitchen cold tap for just asecond, the pump stays on and the dishwasher fills in a more normal 20seconds or so.I phoned the Salamander helpline, and he said it was something to dowith the surge of water being too much for the solonoid and "bouncing"it closed again. Does that make sense?Anyway, he suggested a pressure vessel somewhere in the system toabsorb the shock or surge of water.And yes, I've tried turning the service valve gradually closed. Allthat does is induce quite a loud "swooooosh, swooosh" as the surgerushes by the constriction.Also, would that help my "turn the tap on, get a trickle for half asecond, then a sudden trouser-splashing torrent" problem?For that, the local plumbing centre suggested a gate valve closed offa bit, rather than a pressure reducer. But it's not the pressurethat's the problem, it's that suddent gush when the pump kicks in.So, before I go spending what looks like being =A330+ on a pressurevessel, is that going to help?Thanks!

Jul 30, 2010 22 Replies

Rate this thread:

<me9 15 years ago

For use on a high pressure mains system. Suck it and see -- take it out and see how it goes.

Vote

Tim Downie 15 years ago

Just goes to show that everyone gets lucky occasionally. ;-)

I'd be tempted to just remove it and if you're worried about the effect of high inflow into your machine, just use the inlet valve to your dishwasher as an adjustable flow restrictor.

Tim

Vote

lardconcepts 15 years ago

Decided to just drill out the tiny holes but keep the restrictor. Works a treat!

Thanks, everyone at uk.d-i-y! I've learnt (and saved!) a lot!

Vote

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required