The seasonal transition from a dormant, winterized system to an active irrigation setup requires careful steps to prevent property damage and ensure efficient watering. Reactivating the system too quickly can cause significant problems, such as pipe ruptures or water hammer, a pressure shockwave that occurs when water flow is suddenly started in empty pipes. A methodical approach, beginning with a thorough inspection while the water remains off, will ensure a smooth and damage-free startup. This process transitions the system to operational status, ready to deliver water without leaks or wasted energy.
Preparatory Steps Before System Activation
A thorough inspection of the entire irrigation system must be completed before water is reintroduced. Begin by checking the main controller unit, ensuring it is powered on but set to the “off” or “rain mode” position. This prevents accidental zone activation during startup, which could damage the pump or valves.
Visually inspect all exposed components, including the backflow prevention device, above-ground pipes, and sprinkler heads. Look for signs of damage from freezing, such as cracks in fittings or displaced sprinkler heads. Confirm that all drain valves and winter blowout ports, which were opened for winterization, are securely closed to prevent immediate water loss upon startup.
Carefully Reintroducing Water Supply
Reintroducing the water supply is the most delicate step, requiring caution to avoid pressure surges. Locate the main shutoff valve for the irrigation system, typically found in the basement, utility room, or an outdoor valve box. Open this valve very slowly, turning it only a quarter of the way open at first. This allows the empty main lines to gradually fill with water and air to escape.
For systems with a backflow prevention device, a specific sequence is required to avoid internal damage. Ensure the test cocks—the small slotted screw heads—are closed, with the slot perpendicular to the valve body. On a Pressure Vacuum Breaker (PVB) or Reduced Pressure (RP) device, first open the downstream ball valve (closest to the sprinkler system). Then, slowly open the upstream ball valve (closest to the water source). This gradual pressurization allows the internal check valves to seat properly.
Testing and Calibrating Sprinkler Zones
Once the main line and backflow device are fully pressurized, run each zone individually to check for functionality and leaks. Use the manual function on the controller to activate the first zone for a short duration, typically one to two minutes. As the zone runs, walk the area to look for obvious signs of trouble, such as geysers of water indicating a broken pipe or a head that fails to pop up.
Observe each operating sprinkler head for proper function, including full pop-up height, rotation, and correct spray pattern. Use a specialized tool or a flat-head screwdriver to adjust the arc and distance of the spray, ensuring the water lands efficiently on the intended area without overspray onto pavement or structures. Low-pressure issues often point to a hidden underground leak or a broken head elsewhere in that zone, robbing the other heads of water.
Setting the Controller and Addressing Common Issues
With the physical components verified, the final step is to program the system controller for the season. Reset the controller to the correct date and time, as these settings are often lost during the winter power-down. Set a preliminary watering schedule appropriate for current weather conditions, focusing on short, initial run times to acclimate the landscape.
Minor issues are common during startup and can often be addressed with simple fixes. If a single sprinkler head is not popping up, the cause may be a clogged nozzle filter, which can be cleaned by rinsing away debris. A slight “weeping” from the backflow preventer’s test cocks might be fixed by gently tightening the screws a quarter turn. Persistent leaking, however, may indicate a damaged internal component requiring professional repair.