Feeding a Water Butt to an Attic Tank

championc

Hi all,

I installed a 210l water butt last Sunday (bought in Aldi). It rained on Monday and I couldn't believe the fact that then, on Tuesday morning, the damn thing was full to the brim !!!

If I was to consider re-using this in the house, for maybe toilets (I know, I would need to do a bit of plumbing work), what would I need maybe pump and filtration wise ? Could I use some filtration to make this possible for use in showers too ?

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K.Flyer

Here is the link to the original thread on the subject. Lots of information and suggestions on it.
http://touch.boards.ie/thread/2056609584

Joey the lips

There is a pump for sale in lidl this week that should have enough power to pump this. My concern would be you might need a filtration system for the water so a second tank with propper support might be needed

Dtp1979

Joey the lips wrote: »

There is a pump for sale in lidl this week that should have enough power to pump this. My concern would be you might need a filtration system for the water so a second tank with propper support might be needed

Ye them lidl pumps look ok. A very cheap grundfos MQ. don't use rainwater except for toilets

murphaph

Dtp1979 wrote: »

don't use rainwater except for toilets

The housebuilder we're going with here in Germany offers a 5700 litre buried concrete cistern + pump and associated pipework to operate toilets, garden hose and interestingly the washing machine from filtered rain water (for €6350 including excavation and fitting of the whole lot). In fact they claim that rain water is usually better for the clothes and washing machine as it's soft water, not hard. They won't connect it to anything else.

Of course water is metered here and is not cheap, so it makes economic sense to capture it and use it to offset mains demand as much as possible.

Dtp1979

murphaph wrote: »

The housebuilder we're going with here in Germany offers a 5700 litre buried concrete cistern + pump and associated pipework to operate toilets, garden hose and interestingly the washing machine from filtered rain water (for €5700 including excavation and fitting of the whole lot). In fact they claim that rain water is usually better for the clothes and washing machine as it's soft water, not hard. They won't connect it to anything else.

Of course water is metered here and is not cheap, so it makes economic sense to capture it and use it to offset mains demand as much as possible.

Ah ye it'd be ok for machines too. I just meant not for skin contact

murphaph

I can see buried cisterns taking off in Ireland as water metering is introduced domestically. No shortage of rain so the madness of treating water to drinking quality only to flush it down the jax will be forced into peoples minds.

championc

Thanks @Joey

I bought one of those Lidl pumps. Any suggestions on what relays / controls I need to sense the water levels at both ends and to run the pump automatically to keep the roof tank full but only when the butt has water above a certain level ?

Benster

Hi championc, I've been working on my own system for a good few months now, collecting rainwater for use solely in the toilets. Your idea sounds a lot like my own plan. I have the collection method all sorted and now I'm up to the point where I have to install the 2nd tank and plumb in the pump. I also got the Lidl pump, but over a year ago, shows how long I have been thinking of doing this! I have it in mind to post a "How-To" about the whole thing once I'm happy with it.

Every part of the process so far has been on a "test it and see" basis. The main reason is to have an alternative water source for the toilets as where I live in Meath we occasionally are without water due to bad planning decisions by the County Council back in the day (normal pressure is terrible and we often drop below the threshold to get it up to the attic). I could have installed a larger reservoir to hold mains water but I thought the rainwater way would be a better use of the resource and may also be more economical come the water rates (depends on the pricing for that though).

I got the 210ltr barrel from Woodies, then a long length of flexible pond pipe from a garden centre and linked that up with a diverter on the gutter. I have a few levels of in-line filtration built in, from a wire mesh in the diverter to take away the biggest lumps of moss etc. to changable "milk socks" on the end of the pipe in the barrel to catch the finest particles. You get those in agri stores, dirt cheap too.

Regarding controlling the pump, I have set myself a mini-project to use a Raspberry Pi computer. I have a software background, but there are a lot of areas in this that I have no experience, so I'm learning a lot on the way. After a LOT of research on the net, I have got float switches for the tanks, relays to control mains power and I'm currently working my way through the Python language. Hopefully at the end of this I'll have a working pump controller. I know there are probably less complex ways to do all this but most of those seem to entail forking out a lot of money for proprietry systems that do not link to anything else other than the manufacturer's other products.

The electrics are one area I will have to get a qualified spark to give the all-clear on as well. This is a shoe-string project but that's one area I don't want to cut corners on, too risky.

Hopefully this has given you some inspiration. Check out Youtube and reuk.co.uk for more.

Cheers,
B.

championc

Thanks @Benster

Yes, we look to be heading in the same direction. I just wonder at the levels of filtration given the fact that it's just going to be flushed down the toilet - although I accept that you cannot have a load of moss etc going through the pump.

I'm a fan of the Pi and use it to send Solar and Electricity data to Xively.

I was discussing the "Controls" side of this project with a neighbour last night. From what I can tell, I plan to get 3 controls.

1. A Level switch for the Butt - If the level drops too low, is will NOT allow the pump to work
2. A Pressure switch for the riser to the Attic Tank - once the attic tank calls for water (based on the ballcock), the pressure in the riser will fall and so, I want the pump to activate if the levels in the butt are OK

So I would plan to wire 1 & 2 in series - so BOTH must be OK to run the pump

3. An Level switch on the Attic Tank - if the level is too low (the Butt has failed to fill the tank), then a valve on the rising main will be opened in order to fill the Attic Tank to a minimum level

So the overall idea is - The butt fills and feeds the attic tank which fills the cisterns. If the butt is empty, the pump will not operate and the attic tank will be topped up from the rising main.

So this is a simple system, electrically circuit based essentially using just switches to drive a relay which will operate the pump or keep it off. You may end up over complicating things with a Pi TBH.


Can anyone else out there sanity check what I am proposing to do ?

Giving it holly

Hi guys
If you can afford a reverse osmosis filter and filter the water before it enters the house, it should be safe to use for showering and general use except for drinking. The rainwater is clean before it hits the roof so the only contaminates in the water is what is collected once it is on the roof.
Also keep the tank out of sun light as bacteria will develop in the tank.
I am a plumber and am about to install a 1000 lt tank and pump to supply my home. I don't understand ye need to use a computer program to control the system?? A pump with a flow switch and pressure switch will control the pump. Connect to the mains in the attic with a non-return on the mains and supply from tank. The pump pressure will dominate over the mains pressure while there is water in the butt or what ever you are collecting water in.

Benster

championc wrote: »

You may end up over complicating things with a Pi TBH.

That is a possibility and the more I get into it, the more work there seems to be there. An electric-only system as you describe does sound much more simple. It might not have the flexibility of a computer controlled solution though, eg for status messaging, recording statistics etc. Would be interested in the details of that once you have them worked out.

@Holly: what sort of pump are you thinking of?

Regarding the rising mains backup, I was thinking of taking a spur off the mains pipe to the existing tank and linking that to a ballcock in the RW tank. The RW ballcock would only open when the water is really low, ie below the level of the float switch indicating low level for the RW pump controller. A question for a plumber would be what sort of stress would a ballcock put on the tank sides if it spends most of its life fully submerged?

And on filtration level, as long as I get the small, visible particles out, that will do. The final stage with the milk sock seems to take care of that, even if it does need changed every 3-4 weeks.
There is a ton of bacteria in the water from the birds continously perched on the roof, and the summer heat is a concern there. Once it's all working satisfactorily the plan is to wrap the tank (or tanks) with insulation, primarily for the winter. If I also box it in with a wooden "shield" it might keep the worst of the direct sunlight off it. If I go away for a week or two's holidays, what state will the attic tank be in then? Bacteria soup? Will some sort of flush and refill process have to be put in place? All questions for v.2...