Rainwater harvesting

[Jeremy Harris]

50 minutes ago, Bitpipe said:

 

Ok, that's good to know - I just attached a garden hose to the end of the old pump with a 1" to hozelock fitting but this one will obviously need some better thought!

 

 

They work fine with just an open hose on the end, it's only if you fitted a tap to it that you'd have a problem.  If you only turn it on and off with the pump, then it'll work a treat.  Pressure might be a bit high, though, so it might be worth looking at one of the smaller pumps that Ibo stock.  Our one of those pumps was put in as a temporary replacement, after we wore out the original Grundfos during all the sediment problems with our borehole, so has been supplying all the water to our house for maybe three or four years.  The borehole people gave me a free replacement Grundfos pump as a part of the settlement, and I keep meaning to get around to changing it over, but as the Ibo pump just seems to work OK I've not got around to it.  At a guess it's pumping around 300 to 400 litres per day, everyday.

[Miek]

You could avoid a submersible pump altogether and just get a pump and pressure tank set (about 750w minimum for good hose output) to lift the water out of the tank ( assuming its below ground?), just needs a foot valve on the suction end to keep the pump primed. 

 

I do this to boost the water pressure to my Polytunnel tap which is fed from rainwater from the shed roof into 2 ibc's. Works great ( I have a 1.5kw pump so lots of oomph) 

 

Downsides are the pump is noisy and frost protection is necessary 

Advantages are cost, and easy access to the pump. 

 

 

[Pocster]

Perhaps ?

 

https://www.guttermate.co.uk/mains-back-up-box.html

[PeterW]

1 hour ago, pocster said:

Perhaps ?

 

https://www.guttermate.co.uk/mains-back-up-box.html

 

It has a class one air break in it, quite clever as it essentially flows from either the left port to the tank, or if the tank somehow overflows then it flows from the right as an overflow. 

 

Still a a lot of money for a couple of bits of plastic and a valve ... 

[ProDave]

6 hours ago, JSHarris said:

 

 

They work fine on their side.  The only thing to watch is that they are a positive displacement pump, so they need to be turned off before a tap is fully closed, or have a pressure vessel and switch to turn the pump on and off.  Might be an idea to just fit a cheap pressure relief valve in the outlet as a safety device.  If the outlet is turned off or completely blocked the pressure rises to a very high level.  I've accidentally done this and had a 15 bar pressure gauge pegged at the end stop.  IIRC, 15 bar is way over the maximum pressure for normal MDPE pipe.

A private supply near here had that, the relay that switched the pump had welded shut, the pump just kept going.  The Gauge was off the end of the scale, way over the rating of any of the pipe or the accumulator.  They only knew something was wrong because all the taps in the house were letting water by.

[Bitpipe]

14 hours ago, ProDave said:

A private supply near here had that, the relay that switched the pump had welded shut, the pump just kept going.  The Gauge was off the end of the scale, way over the rating of any of the pipe or the accumulator.  They only knew something was wrong because all the taps in the house were letting water by.

 

Ok, what's a fool proof method to use one of those safely then? I ultimately want a hozelock tap end that I can connect the sprinker / hose to when I want to use the water.

 

Feel free to treat me like a complete idiot

 

 

[ProDave]

4 minutes ago, Bitpipe said:

 

Ok, what's a fool proof method to use one of those safely then? I ultimately want a hozelock tap end that I can connect the sprinker / hose to when I want to use the water.

 

Feel free to treat me like a complete idiot

 

 

This one, I replaced the pathetic relay (supplied as part of a package) with a much better rated contactor.  And the plumber fitted an over pressure blow off valve to the accumulator that would just dump the water if the pressure went above 6 bar. (the accumulator was rated at 10 bar)

 

I would have thought the over pressure relief valve should have been there to start with?

[Jeremy Harris]

We've been using an optical pressure switch on our system since I first got it going, so around 5 years ago now.  I wasn't sure about it, so bought a spare, and wired it up using garden extension lead connectors, so I could swap it out for the spare quickly if need be (I pre-wired the spare with the same connectors).  So far it's been very reliable, and seems to have a decent quality relay inside it: https://www.ebay.co.uk/itm/151020-Automatic-Water-Pump-Pressure-Controller-Electronic-Adjustable-Switch/272751286212?epid=703592864&hash=item3f813e57c4%3Ag%3A4AwAAOSwaNlawMXN&LH_BIN=1

[Bitpipe]

Helpful chaps but not idiot proof enough for me

 

What goes in between the pump that Jeremy recommended and a hozelock connector ?

[Jeremy Harris]

53 minutes ago, Bitpipe said:

Helpful chaps but not idiot proof enough for me

 

What goes in between the pump that Jeremy recommended and a hozelock connector ?

 

 

I haven't bothered, but if you want to be absolutely bomb-proof then just fit a pressure relief valve

A 5 bar one should be about right, as that'll only pop off if there's a serious obstruction.

 

Alternatively, just don't bother to fit a tap or pressure switch, and just have an open-ended Hozelock connector.   You can then just turn the water on or off with a switch controlling the pump.

[Bitpipe]

2 hours ago, JSHarris said:

 

 

I haven't bothered, but if you want to be absolutely bomb-proof then just fit a pressure relief valve

A 5 bar one should be about right, as that'll only pop off if there's a serious obstruction.

 

Alternatively, just don't bother to fit a tap or pressure switch, and just have an open-ended Hozelock connector.   You can then just turn the water on or off with a switch controlling the pump.

 

That was more or less what my previous arrangement was - I had a 1" BSP to hozelock on the outlet of the pump and just used the outdoor socket controlling the pump.