The winters across the United States have been remarkably cold in recent years, so much so that even here in Central Florida we have experienced below-freezing temperatures. In case you didn’t know, there is something other than your palm trees that you need to protect when Jack Frost makes an unscheduled visit to the normally balmy south: your irrigation system. Freezing weather can cause virtually irreparable damage to an irrigation pump. With new bargain-brand pumps starting around $300 plus the cost of accessories (PVC fittings, glue, etc.) and potentially labor, the savvy homeowner or property manager should take precautions to protect their property in the event of impending winter weather.
The anatomy of an irrigation pump and why freezing weather can cause damage
An irrigation pump can essentially be divided into two sections: the motor and the impeller housing. When power is applied by a sprinkler system’s timer, the motor engages and turns the impeller which then draws water from the well and pushes it through the rest of the system to the sprinkler heads. In order for the impeller to draw water from the well, it has to be primed. In other words: the impeller housing is full of water! What this means is that if the weather gets cold enough, the water in the impeller housing will freeze and expand, which will literally cause an impeller housing to crack just like a soda can that has been left in the freezer too long. This type of damage can sometimes be repaired, but more often the housing or even the entire pump assembly will need to be replaced.
What you can do to prevent freezing weather from damaging an irrigation pump
Fortunately, damage to an irrigation pump caused by freezing weather could not be easier to prevent by draining the water from the impeller housing before freezing weather occurs. There are normally two plugs on the front of an irrigation pump assembly. The plug that is located on the bottom of the impeller housing (below the intake of the pump) can be removed with an adjustable wrench, at which point the water will drain from the impeller housing which will render it freezer-proof. Important note: After draining the water from the pump, disable the irrigation system either by the 220V breaker normally located inside the main breaker assembly or by disabling the sprinkler timer. Running the pump “dry” can be very bad for the pump and can damage the motor or reduce its useful life.
Is freezing weather the only time the pump should be drained?
Not necessarily. Depending on what type of grass you are watering, you may be able to drain and disable your pump long before freezing weather occurs, which will not only save electricity, but will also put you ahead of the game and save you from forgetfulness if freezing weather occurs. Most types of grass that are common in the Southern U.S. go dormant during the winter months. Watering a lawn during this season does little for the grass and can actually promote the growth of fungus and other undesirables. Check with your local lawn care experts to determine if and when it is appropriate to drain and disable your sprinkler system.
Contact American Irrigation Services for advice on winterizing your system.