Helpful planning hints:

SHRUBS, FRUIT TREES AND ROSES:
In the case of shrubs, fruit trees or roses place one Microjet® at the base of each stem. (Roses do not like wet leaves so the jet must be installed near to the soil surface)

SMALL BORDERS:
For borders approx 2m wide run the supply line down the centre of the bed placing 360° jets between the plants.

LARGE BORDERS:
For borders larger than 2m run the supply line down the back of the bed and install a T-piece with a second supply line running down the front of the border. Use 180° jets at 1.5m intervals on both lines.

STAKE ASSEMBLY:
Where you wish to take just one jet to a particular plant, which is removed from the lateral line, use the stake assembly.

INSTALL A CHOKE:
Should one Microjet® be required to operate for limited periods only, a choke can be installed to shut off the jet entirely or reduce its output.

WHEN TO USE EMJAY®:
Should you wish to restrict the flow of water on one particular sprinkler line, for example where one line serves a small bed, install an Emjay flow control on the lateral line.

Installation

1

Lay your Microjet® poly-pipe along the planned circuit lines according to the plan.
(To make the coiled pipe more manageable leave it in the sun for a while to soften)

2

Attach the polypipe to your tap using a tap connector.

NOTE: If you wish to install a multi station supply from an automatic timer the easiest method is to fit an extension piece (standard copper pipe) with as many taps as you need irrigation stations.

3

Connect the circuit polypipes to the control valves and install along the circuit lines any T extensions lines along the circuit, according to your plan. Turn on the tap to flush out any soil or stones that may have entered the pipe.

4

Using the Microjet® installation spanner pierce the polypipe and screw in the riser tubes (Available in 2 lengths). When making the holes ensure the pipe is cooled to the water temperature and the holes are made exactly at the top of the pipe.

5

With the riser pipes installed flush the entire system again thoroughly, to clear any debris that will block the jets.

6

Now install end plugs on the main supply line and all the extension lines.

7

Install the jets and test for proper coverage. Mistakes are easier to correct now than later. Use mistake correctors to re-seal incorrect holes.

8

Now dig the trench where the pipe is to be installed just deeper than normal gardening operations. Remove any sharp objects and stones from the trench that could damage the pipe.

9

Lower the entire assembly into the trench and backfill starting from the riser tubes to ensure they stand vertically. If you do not intend on burying the pipes, use riser tube stakes to hold the riser tubes vertical. Also, use pins to keep the polypipe in place. It is recommended that you cover the tube with mulch if it runs close to your plants, as they could otherwise be burnt by the tube heating up in the sun.

Installing your Microjet® system is easy and rewarding. No more hours of watering with the garden hosepipe, no more plants suffering through too much or too little water.

With careful planning of your Microjet® system and correct installation along with regular feeding, your garden will blossom. Microjets® put the right amount of water in the right place and once installed are virtually maintenance-free.

Establish Your Water Pressure and Water Flow:

It is very important to establish what your water pressure and water flow is, as this will affect the number of sprinklers that can operate at the same time.

  1. To establish your water pressure: Turn off all water that comes from the same source. Use a pressure gauge (available at any hardware store) and screw it onto your faucet(tap). Open the tap in full, to get a reading.

    Pressure can vary during the day, so it is best to do this reading at the time that you will want to water. Early morning or late afternoon is best, when less water will be lost to evaporation. The water pressure is measured in kPa(Kilopascals) and the average KPa for most homes is 2.5-3 bars or 250 – 300 kPa

  2. Now determine your waterflow: The simplest method of establishing your water flow is with a standard 10 litre bucket and a stopwatch. Place the bucket under the tap and open the tap fully. With a stopwatch, time how long it takes for the bucket to overflow. This time is an accurate guide to your available water supply/flow.

The table below shows how many jets, with the different rates of discharge, you will be able to install on one circuit, with your water pressure. The standard base used is a blue base. The green base would be used if you need your water to reach further (for example your garden bed is wider) and the white base would be used for speciality sprayers only, where higher water pressure is needed.

Note: You can mix blue bases with green or white bases on the same circuit.

Coverage area
text
Pressure
(kPa)
Discharge
(l/h)
Dia
(m)
Rad
(m)
Rad
(m)
Dia
(m)
Blue Base
1.0mm
orifice
50
100
150
200
250
22
32
40
47
53
2.5
3.1
3.55
3.76
3.9
1.7
1.8
2.05
2.45
2.9
1.7
1.8
2.05
2.45
2.9
1.5
3.15
4.2
4.85
5.2
Green Base
1.3mm
orifice
50
100
150
200
250
35
52
64
75
83
3.15
4.1
4.8
5.35
5.7
1.9
2
2.35
3
3.9
1.9
2
2.35
3
3.9
1.75
3.7
5.1
5.75
6.1

Establish Lateral Line Diameter:

For an efficient irrigation system, it is important not to exceed the number of jets you may install on one circuit and secondly to use the correct lateral pipeline diameter.

NB. A smaller pipe diameter decreases your water pressure. The greater the pipe diameter, the greater the volume of water it can handle.

If possible, use the polypipe with the largest diameter (20mm). Install using a compatible Full Flow R, class 3 LDPE pipe, which handles 3 bar pressure.

DIAMETER OF POLYPIPE:
BLUE BASE
(1.5m spacing)
GREEN BASE
(2m spacing)
WHITE BASE
(3m spacing)
13mm
20m (13 Jets)
15m (10 jets)
8m (3 jets)
15mm
35m (23 jets)
22m (11 jets)
12m (4 jets)
20mm (recommended)
61m (41 jets)
37m (19 jets)
14m (9 jets)

NB. The table above indicates the length of pipe from the installation of the first jet and does not include the length of the pipe from the tap to the first jet.

Planning your system:

Start by making a scale drawing of your property. Include outlines of your flower beds, borders, shrubs and lawn. Also indicate areas not to be watered like the driveways, patios and buildings. Remember to show your water supply points (taps, boreholes)

system planning house illustration

Plan Your Microjets®:

Microjets® are manufactured in different colours. The colour coding of the caps indicate their spray patterns (360°, 180° and 90°). The base colour indicates the rate of water discharge. Using your scale drawing and the tables below, plan the positions of your microjets®. (Blue bases are the most commonly used).

Colour Coding:

Spray patterns as shown below are indicated by the colour of the caps

CAPS:
BASES
DISCHARGE AT 150kPa
MICROJET®
SPACING
Red 360°
Blue
40L per hour
1.5m
Blue 180°
Green
65L per hour
2.0m
Green 90°
White
174L per hour
3m
Black 2 x 20°

Irrigation Circuits:

For most gardens it is necessary to divide the irrigation areas into circuits as the available water supply does not allow for
the simultaneous operation of all the jets needed.

Use the tables above to ensure you do not exceed the number of jets planned for each circuit and to establish your lateral line pipe diameter. It is advisable to use separate circuits for the North and South sides of the house as the South side will need less water than the North side.