Technical “
Make sure that if your compressor produces hot air, then you cool it before it enters the piping by, for example, running the air through a metal pipe or long length of hose to absorb the heat
again, allows any remaining water to expand without causing any damage.
With valve‐in‐head sprinklers, turning each head to the ‘on’ position manually operates the sprinkler and removes any pressure within the pipes. This operation also prepares the system for open up or re‐ pressurisation in the spring, allowing all the trapped air to bleed out of each head, which ultimately prevents damage to the sprinklers.
With compressed air
First thing and most important point to be mindful of is the fact that air compresses and water does not. This makes air very dangerous and is one of the main causes of sprinkler damage when not undertaken properly and as per the manufacturer’s recommendations. The results of this will not be seen until the system is re‐pressurised in the spring and things are not working. As previously mentioned, the majority of UK systems are drained via gravity and not compressed air and it is important to note that it is a recommendation in colder climates to prevent frost damage, so it is a decision the client needs to make when draining the system down.
When using compressed air in a system there needs to be a way for the air to escape; there should be no dead ends for the air to build up against either, as this will be what the air builds and builds against until something breaks.
Slow and steady is the best and only option to prevent damage to pipework. Be
consistent and drain the system slowly over several days (depending on system size) if necessary. Toro recommends a minimum of 35 psi, going up to a maximum of 50 psi. This should create enough air to move all the water out of the way so there is a volume of water moving down the pipe ahead of the air. It is important to note that, if you are pushing water through a sprinkler, that only one operation takes place and, if there is a requirement to operate more than once, that you adopt the riserless operation to prevent damage from compressed air and water.
Heat is another important consideration. Ideally the temperature should be low to prevent damage, like melting diaphragms and other plastic components. Make sure that, if your compressor produces hot air, then you cool it before it enters the piping by, for example, running the air through a metal pipe or long length of hose to absorb the heat.
There are varying opinions on where to blow out from. Some say the high point, while others say the low point is best. Some move the compressor around from low point to high point, whilst others (and we are in this camp) blow from the water source. By blowing from the water source, you know the air has taken the same route round as the water, and that it has been through all the piping.
Start by closing the main water supply valve, then open the drains and drain the mainline as much as possible. When all the water has been drained, close the drain
ROB GREEN’S TOP TIP
It’s best to use a remote control device for this operation because the amount of time each sprinkler should operate will vary.
valves and/or hosepoints etc. Activate each automatic valve or sprinkler manually from the controller or remote control, allowing each valve to remain on until all water has been expelled from the sprinkler heads ‐ again only once, unless removing the riser! When the blow‐out is complete, shut off the compressor and give the remaining water some time to settle into the low points. This usually takes a few hours. Once that’s done, go back to the low areas to expel the last remaining water. Quick couplers around the green etc. should also be activated to clear them of water.
For a chat about your own irrigation system needs, contact Robert or one of his team members on
info@reesinkturfcare.co.uk
128 I PC DECEMBER/JANUARY 2018
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80 |
Page 81 |
Page 82 |
Page 83 |
Page 84 |
Page 85 |
Page 86 |
Page 87 |
Page 88 |
Page 89 |
Page 90 |
Page 91 |
Page 92 |
Page 93 |
Page 94 |
Page 95 |
Page 96 |
Page 97 |
Page 98 |
Page 99 |
Page 100 |
Page 101 |
Page 102 |
Page 103 |
Page 104 |
Page 105 |
Page 106 |
Page 107 |
Page 108 |
Page 109 |
Page 110 |
Page 111 |
Page 112 |
Page 113 |
Page 114 |
Page 115 |
Page 116 |
Page 117 |
Page 118 |
Page 119 |
Page 120 |
Page 121 |
Page 122 |
Page 123 |
Page 124 |
Page 125 |
Page 126 |
Page 127 |
Page 128 |
Page 129 |
Page 130 |
Page 131 |
Page 132 |
Page 133 |
Page 134 |
Page 135 |
Page 136 |
Page 137 |
Page 138 |
Page 139 |
Page 140 |
Page 141 |
Page 142 |
Page 143 |
Page 144 |
Page 145 |
Page 146 |
Page 147 |
Page 148