Pond Pump Electrics

[dibsdiy]

I posted my original question in General DIY re a new pond pump but maybe I should have tried electrics. I am having trouble with my garden pond pump. I am puzzled because I have a RCD (?) in the conservatory leading to twin sockets outside for the pump and filter. When I plug these two in the outside sockets, they trip the RCD. But, if I run the pump and filter on an extension lead from a socket in my house, they both work. I am told by an electrician that there is nothing wrong with the sockets outside or the RCD. He thinks the filter still works with the RCD but that a fault in the pump may be causing the little RCD to trip. I really don't know which way to go, get another electrician in or buy a new pump. The pump is 15 years old. Can anyone please advise which way I should go? Many thanks for any help.
Read more: https://www.diynot.com/diy/threads/garden-pond-pump.481510/#ixzz4fcylzZSh

 

[John D v2.0]

Sounds like they have too much earth leakage, do you have an RCD in your consumer unit (covering the inside socket you're using?)
Given it's an outside water thing I'm guessing it's got water in and should be replaced. I'm assuming the electrician tested the rcd using a proper tester before he declared it good.

 

[dibsdiy]

Thank you for your quick reply, the inside socket is just off the usual in house meter, the electrician did have various testing equipment which he demonstrated to me the outside sockets were working (a round unit plugged in giving off a continuous noise - sorry - not very up on these things) and he also tested the inside RCD. It is a puzzle. Many thanks.

 

[John D v2.0]

Sounds like he didn't test it properly, the correct test involves a bigger unit where he sets it to half rated current to make sure it doesn't trip early, and then tries full rated current to make sure it trips fast enough. If he was inclined he could have ir tested between earth and l/n on the pump, but I'm not sure if they have designed in leakage and I wouldn't expect that as it's not a standard test.
However having said that my money is on a faulty pump with an insulation failure leaking to earth. If you can afford to change it I would.

 

[dibsdiy]

Thank you for your comments, I am now thinking of a new pump as I have had my use out of the old one and feel it is only a question of time anyway with it as it is so old so wouldn't be a bad buy. Can you advise what I should be looking for in qualifications an electrician should have? Many thanks.

 

[John D v2.0]

Not sure, one of the actual electricians on this site will be able to help you there, but I'm sure there's an element of luck in there to find a good one! Just south your own research and ask for explanations, and it should become clear.

 

[flameport]

a round unit plugged in giving off a continuous noise

Those devices are next to useless, they only suggest that the wiring to the socket might be correctly connected. There are many faults which they cannot detect.

Do other things work in the outside sockets? Such as an electric kettle?

the inside socket is just off the usual in house meter,

Post a photo of the conservatory RCD and also the main fusebox/consumer unit in the house.

 

[dibsdiy]

Photos attached. Hope they are OK.

 

[dibsdiy]

I just reset the RCD and both outside sockets worked with a hair dryer. When I put the two pond plugs back in they didn't work. Thank you for your help.

 

[dannyboi2003]

You don't have an RCD covering he house sockets that is why the pump worked on the extension lead. The pump is faulty and needs to be replaced, the RCD is doing its job and keeping you safe. You said above that you have two pond plugs yet you only talk about one pump, what is the second plug for?

 

[dibsdiy]

The water from the pump goes through a Bioforce separate filter (with UVC light) outside the pond which is run from the second plug. Thank you for your help, I will get a new pump.

Many thanks again,

 

[ericmark]

I would try just the pump, then just the filter so you know which is faulty. The pond pump in the main has the windings in epoxy resin, however the more expensive types have an air filled chamber and used oil to keep the water out, there are normally plugs to remove to renew the oil and test it, if water has got in then the oil goes white, I had some adapted plugs with a car valve on it, I would put 15 psi in over night and see if it held, there would be a little leak but not much, both in the oil chamber and windings, some times it was the cable damaged, I have seen water being forced out of a cable when under test. I would strip down faulty pumps and repair, like an axe the pump would last forever, it may need a new handle every so often or a head every so often, but in the main the domestic model you just bin and get new, very few are designed to be repaired.

 

[dibsdiy]

I'm pretty sure it is the pump, as the light comes on in the filter. Thank you for your help.