Rainwater Harvesting water pump not working

[RSE]

Hi guys, I'd appreciate any help on this.

I have a large rainwater harvesting tank sunken in my back garden (wife dug the 2m square hole whilst I carried the soil through the house) - the tank works perfectly; the submerged pump on the other hand periodically goes faulty and I've had to replace the unit in the past (its a Hydroforce (HydroForce Clean Water Submersable Water Pump - https://www.hydroforcepumps.co.uk). My current pump has also gone faulty and I'm trying to diagnose and fix it rather than spend £290 for a replacement). Its a float pump which operates when water pressure in the inlet hose drops.

The pump is wired to an internal 13A plug socket and an indoor control unit controls when the pump is switched on (to pump water to a 15m high roof water tank, a tank which feeds the toilets). Recently the pump has tripped the plug socket ring; to resolve this, I've taken the front cover off the pump and found the earth to be somewhat corroded - I've cleaned the earth connection, coated the earth connection in Vaseline, and the pump can be connected to the mains without tripping the house plug circuit.

However, the pump no longer pumps water either when connected back into series with the internal control unit, or when independently plugged into a wall socket.

I am now reaching the extent of my fault finding skills, and whilst I do have a meter, I have no idea as what I should measure to try a diagnose the problem.
Could anyone help? Thanks

 

[snowhead]

I'd try the manufacturer first.
Then if no satisfaction I'd buy from a different manufacturer.

It's described as a clean water pump.

Rainwater isn't clean.
Does the pump have any type of filter on it's inlet?

 

[Marvo]

Small submersible pumps are almost always not repairable and they're notoriously unreliable. If you plug it in and it doesn't run when you move the float switch around then it's most likely scrap.

 

[Dave1 gp]

I took my pump to a local motor rewinds company who diognosed the capacitor. £15.00. Job done 10 minutes. Resealed soldered joint with IP68 nonsetting Mastic. ?

 

[BenRam]

I took my pump to a local motor rewinds company who diognosed the capacitor. £15.00. Job done 10 minutes. Resealed soldered joint with IP68 nonsetting Mastic. ?

Hello Dave, I don't know what problem you had w/ your pump, but I am having problems w/ my HydroForce pump and £15 sounds way better than £300+ for a new replacement. Can you remember where you took your pump. I too am local to Leicester. Thanks.

 

[telectrix]

one thing to take into account is the length and csa of the cable feeding the pump. doesn't take much VD for the motor to not turn, and burn out stalled.

 

[brianmoooore]

There's also the possibility that you are damaging the motor by overloading it. Contrary to what most might assume, a centrifugal pump works the hardest when what it is doing is the easiest - such as just pumping to a short open pipe.
Have you checked the run current of the pump at any time, and does it have any kind of overload protection.