Pump Check Valves
What does a pump check valve do?
A pump check valve is a one-way valve that prevents water from flowing backward through the pump system when the pump shuts off. Here's how it works and why it's essential:
Primary Function: The check valve allows water to flow in only one direction - from the pump toward the delivery point. When the pump is running, water pressure forces the valve open, allowing normal flow. When the pump stops, the valve automatically closes to prevent reverse flow.
The Gravity Problem: Without a check valve, gravity becomes the enemy of pump efficiency. When the pump shuts off, the water that was just pumped up to higher elevations (like storage tanks, upper floors, or elevated discharge points) wants to flow back down due to gravitational pull. This returning water flows backward through the pump and returns to the original reservoir or source.
The Cycling Issue: This creates a problematic cycle: the pump fills the system and shuts off, then gravity drains the water back down, causing the water level or pressure to drop. This drop triggers the pump to restart, only to have the same thing happen again. The pump ends up running far more frequently than necessary, leading to:
- – Excessive wear and energy consumption
- – Shortened pump lifespan
- – Inconsistent water pressure or supply
- – Potential pump damage from constant starting and stopping
The Solution: A properly installed check valve eliminates this problem by trapping the water in the system after each pump cycle, maintaining pressure and preventing the wasteful back-and-forth flow that would otherwise occur.
