How To Build The Air Actuated Water Valve.
Device produces the ebb-and-flow effect in growing-beds, and provides an enhanced control over frequency, duration, and period of operation in comparison to traditional auto-shipons. It is the low cost alternative to an electronically actuated valve.
- Author: Paulo Marini.
- Time required: 60 to 90 mins.
- Difficulty: Moderate.
Authors: Lemos-Marini, P. Flecher, J. Coleman, G 2014 with the generous support of FabLab Manchester and Incredible AquaGarden.
The enhanced features allow you to:
- increase the irrigation frequency on warmer days.
- stop the ebb-and-flow effect automatically at night for improved aeration of the media.
- manage the flow of water in large grow-beds when ebb and flow siphons tend not to work.
- avoid harmonic synchronization when several auto-shipons are installed together.
The valve uses the compressed air from the air pumps (for the fish tank aeration), two air solenoid valves, and the Aquaponics Lab monitoring and controlling system.
Although it has no perfect seal, with the pressure utilized, it performs its function well.
Cost of replication:
Estimated cost of replication is around £70, not including the Aquaponics Lab monitoring and controlling system. An electronically actuated valve will cost >£350.
This is a working prototype currently in operation and tested in our system. Improvements will be needed to have a fully reliable and replicable model. The two areas of attention are:
1-The air fitting position is sensitive.
2-The elastomer (inner-tube) is theoretically the weakest point in the system. We are currently testing its durability in real operation.
Elastomer (inner tube) was installed on 12/09/2014.
As per 22/08/2015, the elastomer has been working continuously without needing service.
Open Source License
====Copyright Aquaponics Lab 2015==== www.aquaponicslab.org
This documentation describes Open Hardware and is licensed under the CERN OHL v. 1.2.
You may redistribute and modify this documentation under the terms of the
CERN OHL v.1.2. (http://ohwr.org/cernohl). This documentation is distributed
WITHOUT ANY EXPRESS OR IMPLIED WARRANTY, INCLUDING OF
MERCHANTABILITY, SATISFACTORY QUALITY AND FITNESS FOR A
PARTICULAR PURPOSE. Please see the CERN OHL v.1.2 for applicable conditions.
How To Build The Air Actuated Water Valve V.1.3.
Drill Bit – slightly smaller than the threaded part of the hose-tail fitting.
Hole Saw Arbor.
Hole Saw – 64 mm.
Flat Blade Screwdriver.
Acrylic Tube (110mm x 5mm x 500mm) or a 110mm Pipe.
Pipe 50 mm Solvent Weld.
Inner Tube Bike or motorcycle inner tube – 2″ diameter +/-.
Tank Connector 2″ (50mm) Threaded for Solvent Weld Pipe (2).
Jubilee Hose Clips 55-70mm – Stainless Steel (2).
O-Ring – Big (2) for tank connector.
O-Ring – Small for hose-tail fitting.
Hose-tailfitting – Brass Male – 1/8 Bsp Male,1/8 = 3mm Dia,1.
Double Socket Connector 110mm (2).
Socket Plug 110mm (2).
Demonstration of the valve working. Mechanism is stopping the flow of water to the fish tank, forcing it to go up into the growbed.
Drill the centre of the two 110mm socket plugs using the 64mm hole saw.
Place the tank connector first to locate the best possible location for the air connector.
Then, drill a hole for the air connector in the shown position.
Cut two 13cm pieces from the 50mm pipe.
Cut two 10cm pieces from the 50mm pipe.
Sand any leftover or rough edges from all the cut pieces.
Cut a 35cm length of inner-tube.
Cut it following the seal, open flat, and then cut it again into two halves.
Cut a 50cm length of inner-tube.
Insert one big o-ring in each one of the 2 tank connectors as shown.
Take the socket plug with the air connector hole, and insert the tank connector.
On the same socket plug, install the air connector with the small o-ring.
Sleeve both sides of 50cm piece of inner-tube around the two 13cm pipe pieces by approximately 8cm.
Wrap the 35cm flat piece of inner tube tightly on top of one side of the previously sleeved inner-tube.
Screw the Jubille Clip on top of the wrap of inner tube.
Repeat the same procedure with the other side of the 50cm inner-tube.
Take the socket plug with the tank connector and air fitting. Insert one of the sides of sleeved inner-tube into the tank connector.
Insert the other side of the sleeved inner-tube into the other tank connector.
Insert the 10cm pipe in both sides of the tank connector that are still available.
Assemble double socket connectors and acrylic pipe.
Insert the other Socket Plug (without air connector) in one of the 50mm double-socket connectors.
With the acrylic pipe standing horizontally insert the socket plug with the air connector.
Pull pipe from the other side and screw the tank connector.
The valve is complete.
To run this valve you will need two air solenoid valves controlled by the Aquaponics Lab Electronic System, as well as an air pump.
We will develop the other guide explaining how to do it.
I've done it! Success!
Now onto the next task.