The system you have purchased consists of a 20mm spray line which attaches to the ridge of the polytunnel and continues down the door post where it connects to a hose-pipe. The water inlet system pipe contains a ball valve (tap), pressure regulator and hose connector (fig 23a).
Using a sharp knife, cut a section of 20mm pipe 1m shorter than the length of your Polytunnel to form the spray line. At one end of the pipe push in the barbed end stop and at the opposite end fit a barbed elbow. These barbed fittings are a tight fit and may require some force to fully press home (fig 23b).
TIP: Inserting the barb fittings into the pipe can be very tight – holding the pipe in hot water for a few seconds will help.
Fix the pipe to the ridge using the cable ties spaced equally down the polytunnel length along the ridge. Ensure that the pipe with the fitted elbow is at the end where the water supply will enter the Polytunnel. The pipe may bend and weave to avoid fixtures and fittings, but this is allowed. (Leave the ties slightly loose at this stage to allow the pipe to move).
Door Post Pipe System
Turn the elbow in the overhead spray line so that it is pointing in the direction of the door post you have chosen to support the pipe work. Cut a short piece of the remaining 20mm pipe at a length that spans the distance between the elbow in the spray line and the centre of the doorpost. Push a barbed elbow into one end of this joining pipe and push the opposite end of the pipe onto the barbed elbow on the spray line.
Assemble the Water Inlet System using the remainder of the 20mm pipe, and the parts shown) (fig 23c). Use 2-3 complete turns in a clockwise direction of PTFE tape to join the Tap to the Pressure Regulator (fig 23d).
Hold this assembly up to the door post and decide on a suitable height for the tap. Cut the Water Inlet System pipe to match up to the elbow in the joining pipe. (Ensure that the joining pipe is as close to the horizontal as possible). Using the pipe clamp screw this to the door post in line with the joint between the tap and pressure regulator whilst holding the tap at the required height. Clip the pressure regulator into the pipe clamp to prevent the manifold from sliding up and down. Use the nail on pipe clamps to fix the remainder of the Water Inlet System pipe to the door post.
Spray Nozzles
Tighten the cable ties along the ridge and use the hole punch to punch a hole approximately in the middle of each hoop space in the underside see (dia 23e). Insert a down tube adaptor in each hole using the punch for assistance. Assemble the down tube and spray nozzle and insert into each of the adaptors. Note the direction of flow on the Anti drip valve (fig 23f).
TIP: The Anti Drip Valve used is designed to prevent the sprayers from dripping when the water supply is turned off. However, low water pressure supplies may not close the valve and so prevent the system form working correctly. If so, these valves can be removed to improve the effectiveness of the system.
Prestige Overhead Irrigation
If you ordered a Prestige Irrigation System then you will need to fit the Water Controller onto the tap of your water source. The water controller is supplied with fittings for
either a 3/4in or 1in male threaded tap. Use the two ‘Hose to Female Click’ fittings to run a hose between the ‘Male Click’ fittings on the Water Controller and the Polytunnel. You will require a hose pipe and may require extra ‘Click’ fittings depending on the type of tap being used.
Click to enlarge
23a
23b
23c
23d
23e
23f