I am still light years away from starting to automate my home which is currently is ranked with the nice to have items.
Too many other priorities first such as painting the house, changing all lights to LED etc.
So if I’m to do anything here in terms of automation, it has to be a very localized solution (mechanical timers for example) and cheap.
This is actually also a great plan and will probably be the easiest. I mean I already have the water tanks and the pump, it is just to get it clean and into the existing plumbing.
What I am wondering about though, is how to operate the pump without burning it out?
I don’t think my pump is the kind that like fighting against a closed tap.
Showering would be a two man job, one to take the actual shower, and the other one to operate the pump outside.
How do I overcome this issue? A proper pressure pump somewhere in the line?
Or it should only be used for bathing. Fill the bath with hot water with this pump and shut it off and be done?
One of those pressure vessel switches that you fit on the pump will work.
There is a clever low tech way to turn your pump on and off when your you need to water your veggies, that will ensure it doesn’t turn on after it rains, and only ever delivers the right amount of water when needed.
I am trying to find the link it is an Aussie invention I think.
A bit difficult to describe but actually very simple and basically foolproof.
I can’t find it, I’ll try and draw it. I thought it was a bit clever.
Edit: The guy literally made it with a basin, a plank, magnet, a brick and an old washing machine solenoid valve. This is the working principle.
My water setup is as follows:
2 x 1000l jojo tanks (must still add another 3)
1 x grundfos smart pressure pump
the 2 jojo tanks are fed with rain & mains water (float valve) the pump feeds the house, solar & gas geysers.
this setup provides full water pressure at all times regardless of the low muncipal water pressure or burst mains.
As Phil mentioned you can just add a pressure switch to the pump. R540 It will switch the pump on when the pressure in the pipe decrease (open tap) and off when it increase (closed tap)
And that little automated thing I drew above is the tap, then you just have a level switch on the tank that cuts the pump supply when the tank is empty.
Question 1: Would that little thingy work on a 1.1kw pool pump? If a toilet flushes, pump starts.
Mmm, methinks now that a 1.1kw pool pump is going to blow the cistern up.
Question 2: Also looking for a cheap simple solution to pump water from a 1000l tank under a gutter to a 5000l tank that is higher. As the 1kl tank fills up with rainwater pump it over to the 5kl tank, then wait again for it to fill up again.
This is what I have done. There is a Sonoff Pow R2 with the pump’s name on to automate this. Just need to find more time.
You will have to check the power rating for the 1.1kw pump and the switch.
I have seen a 0.75kW pump on a cistern working with no problem. Presumably, the pressure setting switches the pump before it blows pipes.
Plenty of solutions, you can use a level switch and a very small pump if you have time to transfer. Just have a think about where to put the pump so it self primes. If the head is not that big, and you have all day to pump there will be plenty of pumps that could be recycled to fit the bill.
Want to keep on using the 1.1kw … it is here, has a cartridge filter to take out the bugs … when I manually start it is it “primed”. Just don’t lift the pipe out of the water. 
What makes me cautious is the force these pumps can pump at, so the 1kl tank would be drained in a few minutes, idea is to fill the 5kl tank ASAP when it rains.
Currently, my fast dirty DIY project has a first flow being a 2200l portable pool. It fills quite fast with a good rain as I have had the house roofs flowing into it. Just have to manually switch on the pump.
If I remove it, I need a smaller tank to get past the house, therein a cheap damn sure solution that that TTT arse cannot mess that up too see. 
My burn fingers still hurts typing … dammit!
Excellent thanks guys, I’m looking into this.
For most modern houses, the entire house is balanced. This means the high water pressure comes to a pressure control valve like this:
And then all other cold supply points in the house branches off after this device. The idea is that at any point that there is a hot connection as well, the two are at the same pressure, and therefore mixers work correctly.
Of course there might be the odd connection that does not branch off after the pressure control valve (ie they are unbalanced). For example, faucets outside the home might just tap directly from the High Pressure supply (cause it doesn’t matter, nothing to balance).
In older houses, before there was mixers, the cold supply for a bathroom might also be unbalanced, because back then you had two different taps which you manually adjusted to get the right temperature, something we inherited from the standard British plumbing setup.
Also, sometimes a plumber will simply plumb a toilet or a washing machine into the balanced side, even though there is no need for balancing (cold only supply), simply because the pipe is right there and it is pointless to put an extra pipe in.
As a result, many houses built in the last 30 years or so have everything (except outside faucets) running from the balanced supply. Which means that if you push your alternative supply into the system right before that pressure control valve, you will have everything supplied except the mentioned outside points.
Now in my house, built in 1975, that is ALMOST the case. It works perfectly for everything downstairs, but the upstairs bathrooms have an unbalanced cold supply. So their cold water taps have no backup supply.
There is however a naughty way of making it work. If I close the cut-off on the street (right after the water meter) and open the relevant valve, I can push water backwards into the rest of the house and have everything work. But this is not really legal. In fact, the changeover setup itself should be designed so that water cannot flow back into the city’s reticulation system… and if you ever need to sell the house, it needs to be compliant or you have to remove it
The better solution is a pressure tank, a kind of “bladder” that holds a certain amount of water under pressure. They look like this:
This you combine with the control unit Louis mentioned. That looks like this:
The job of that thing is to switch the pump off when it hits 4kpa (or thereabouts) and switch it back on below some critical point (1kpa on mine). With the big pressure/bladder tank, it will have more water under pressure and therefore the pump will be off for longer periods, and then run for a longer period when the pressure drops too low. Without the tank, the pump switches on and off a lot more.
For emergency purposes, I find that it works just fine without the pressure tank. For daily use I’d suggest adding the tank to take some stress off the pump.
The bladder is must for everyday use. But be careful with the cheap versions their bladder inside the container perish quickly and need to be replaced way too frequently.
In my system where the pump does not feed the house but rather pump it to a higher tank. That tank is my bladder in a sense.
Also, I find that the house itself has a bit of a balloon effect. Once you have the entire thing “inflated”, it tends to create a bit of a buffer anyway.
I also had a funny incident recently. While on backup water, I heard water dribbling somewhere. Turned out to be a shower. My pressure pump makes a higher pressure than the municipal supply… and suddenly that one tap wasn’t fully closed anymore
Excellent news! I’ll go make sure about having this pressure balance device at my geyser. My house is not very old, probably about 15 years I would estimate.
Believe me I have thought about this also because my existing setup allows me to do that already. Just need that pressure control switch as suggested above. But the idea of having unfiltered rain water in my drinking supply leaves me a little uneasy.
I have time, if it gets done over the next day for free that’s OK with me.
I find that panels I bought years ago are taking up space on the roof that a panel today would make another 150Watts from. So I reclaim that roof space, but I don’t resell those older panels, I just repurpose them for mini-jobs. Little stand alone systems that it is impractical to cable to either from the batteries or from an AC supply. (Or sometimes, just because, … it is easy to find a bit of space for a couple of old panels).
Anyway, so a transfer pump as you describe is awaiting installation.
This isn’t the model I bought, the one I bought was more expensive. I also bought a pool pump size model.
I also have a borehole pump that is actually installed and working that has an inbuilt MPPT controller. Same principle if the sun shines it pumps.
Edit: It looks like they now make them with built-in controllers and cheaper again:
And if you shop around they’ll throw in a foot-valve & three float switches, (the controller already equipped to take them).
So to prevent that, (if you forget to close the cut-off at the street) is to set the pressure from the installed rain water system, lower than that of your city water pressure.
Then also install a one way value to prevent city water pushing back into your rain water system.
Saw that at a friends house, and it works 100%. City water is 2.2bar, and he set his rain water to 1.9Bar.
Edit: I might be wrong here, but does copper not kills bacteria/Germs? If that is the case, then in theory, your house copper pipes should kills all the bacteria in the water?!
I’m not sure under which category I should file this. Should it go under “we drank water from the garden hose and nothing happened to us”, or should it go under something else?
In my childhood home there were two sources of water. The one was from the tap. It came from a borehole, went into a cement dam (which was cleaned maybe every few years and had lots of fauna and flora), and then came to the house in a big old 1.5" plastic pipe. We drank that water and cooked with it. Nothing bad ever happened. It wasn’t the most tasty water, it was a tiny bit brackish, but we’re all fine today.
The other source was a rainwater tank. It was also completely unfiltered. The tank wasn’t pristine either… I cleaned it myself when I was in high school. Rain water tends to preserve itself for the most part, because it has a Ph of around 6.2 courtesy of the carbonic acid that forms in it on the way down, and also because there is no dissolved carbon in it (which is needed for the bacteria to live off). So there was no fauna and flora in this tank, but it nevertheless, there were dead insects and all sorts of interesting things at the bottom of this tank. But that was kinda the point… it was at the bottom of the tank. We drank the clean stuff that sat on top. Again… nothing bad ever happened to us.
But… this was on a farm. The dust is so clean you can eat it. It has to be, cause the sun bakes the life out of it every summer. Whatever dirt was on the roof… would have been clean dirt. I cannot necessarily say the same thing for the roofs in the city.
So… between those two points, I’m not sure how dangerous rain water really is. Mine is unfiltered. We try not to drink it, but we also have filtered water with a little water-cooler-fridge thingy, so it’s easy enough. And as soon as the water outage is over, the new “clean” (really?) water from the council, complete with some residual chlorine, floods the pipes again.
In short, I may be overly relaxed, I’m not sure, but I am not concerned too much about the tank water in the pipes. I will probably fit a filter at some point, but only to keep debris out.