Pump advice

rampantbunny

Setup:
1 large (very) rainwater harvesting tank
1 tank (1000ltrs) in garage attic, which feeds household

I need to get water from rainwater tank to garage attic tank.
I could install a submersible pump in the rain-water tank, but would prefer to locate any hardware in the garage itself. So a shallow well pump is what's needed I think.

The pipe run (for suction) would be 2m vertical (from bottom or rainwater tank to top), then approx. 10m horizontal (along ground between tank and garage), then 2m vertical again (pump mounted on wall inside garage). Finally, the unit would pump vertically around 4m.

Firstly; besides a pump, what other hardware is required. I understand a float switch is required in the attic tank to turn on the pump when water is low (maybe half full), and turns it off I presume?
A friend has mentioned I might need an expansion tank. I understand what these are used for but not sure if required in my situation given I'll only be topping up the tank from when it is around half empty (500 ltrs). So no constant cycling to worry about.

Secondly, can anyone recommend a suitable pump to do this (PM if necessary).
Any advice appreciated.

DGOBS

How are you filtering the rainwater?

rampantbunny

DGOBS wrote: »

How are you filtering the rainwater?

With filters!

Only joking...I have a 5 stainless steel filters ready for installation into a purpose made chamber just before water enters the pipe.
The range from #4 to #80 gauge. Not sure the 80 will let water through quick enough but I'll experiment. I've already a treatment system installed in the garage attic on the output from that tank. UV filter and another 'Auto wash carbon' ...sketchy on the details at the moment as haven't looked back at them in a while.

I also have some stainless steel fan covers (from some old computers) that I plan to install in the gutters to stop any larger debris getting into the down-pipes. More to keep the pipes clean because if I wanted I could trap this all in the filter chamber mentioned.

rampantbunny

No bites?

rampantbunny

Update in case anyone is interested..(and a dear diary entry for myself)...


On the filtration side of things, I'd like to keep the rainwater pipes which feed the filter-box as clean as possible. So to filter rainwater in the eaves I've bought some cheap tea leaf strainer type baskets from Amazon which fit perfectly into the outlet in the eaves which feed into the actual down-pipes.
These will have to be cleaned every so often as they'll probably clog with dirt, but if I become less agile I can remove them and depend on the main filter box to do all the sediment filtering. At this point I'll be letting dirt enter the pipe-work but I might have other problems to worry about in my old age at that point.


In the filter box, I'm making some mounting frames from sheet aluminium into which I'll be inserting my stainless filter mesh. Five filters from size #4 to #80 gauge...prob won't use the 80 as it is very very fine and will probably delay the ingress of water into the tank itself.


On the pump side of things - well I've gone the cheapo route and bought one of Lidls €70 pumps. Will try it out and see how it performs, but on paper at least it runs to the same spec as other pumps I was recommend which were a multiple of the price.
I've set up two float switches; on the garage attic tank and the other in the main rain-water tank. The latter is the master as it cuts all power to the pump circuit if the main tank is empty (dry-run protection). In this scenario the garage tank will be maintained at a certain level by a mains supply on a ball-cock.

I've also been able to rig an indicator light, from the tank float switch to the side of the rainwater tank. At a glance this will tell me if there is any water in the tank. If the light is on, I will know that the garage tank is now being topped up with limescale ridden mains water. Could've gone the smart home route on this and built a fancy schmancy monitoring system, but for no real gain.