Deep Well Pump Pressure Tank: A Comprehensive Guide

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A deep well pump pressure tank is a critical component of a deep well water system, storing water under pressure and providing a reserve supply for the pump to draw from. This comprehensive guide will delve into the technical details, specifications, and best practices for selecting and maintaining a deep well pump pressure tank.

Understanding the Pressure Tank

The pressure tank in a deep well system serves several crucial functions:

  1. Water Storage: The tank stores a reserve supply of water, ensuring a consistent flow and pressure even during periods of high demand.
  2. Pressure Regulation: The tank maintains a specific pressure range, typically between 30-50 PSI, to optimize the performance of the well pump.
  3. Pump Cycling Reduction: By providing a buffer of stored water, the pressure tank reduces the frequency of the well pump cycling on and off, extending its lifespan.

Pressure Tank Sizing and Selection

deep well pump pressure tank

The size and capacity of the pressure tank are critical factors in determining the overall performance of the deep well system. When selecting a pressure tank, consider the following:

Tank Size

  • The tank size is typically measured in gallons, with common sizes ranging from 20 to 119 gallons.
  • The tank size should be chosen based on the well’s flow rate, the expected water usage, and the desired pressure range.
  • As a general rule, the tank size should be approximately 2-3 times the well’s flow rate in gallons per minute (GPM).

Pressure Range

  • The most common pressure setting for deep well pump pressure tanks is 40 PSI, with a switch setting range of 30-50 PSI.
  • The pressure range should be selected based on the well pump’s specifications and the desired flow rate.
  • A higher pressure setting can increase the flow rate but may also result in more frequent pump cycling.

Drawdown Calculation

  • The drawdown of the pressure tank is the amount of water that can be drawn from the tank before the pump needs to refill it.
  • To calculate the drawdown, use the formula: Drawdown (gallons) = Tank Size (gallons) x (Maximum Pressure – Minimum Pressure) / Maximum Pressure
  • For example, a 50-gallon tank with a pressure range of 30-50 PSI would have a drawdown of 25 gallons.

Flow Rate Determination

  • The flow rate of the deep well system can be measured using the stopwatch method or calculated based on the drawdown.
  • To calculate the flow rate, divide the drawdown (in gallons) by the time it takes for the pump to refill the tank (in minutes).
  • For example, if a 20-gallon drawdown takes 120 seconds to refill, the flow rate would be 10 GPM.

Well Pump Considerations

In addition to the pressure tank, the well pump itself is a critical component of the deep well system. When selecting a well pump, consider the following:

Power Source

  • Standard well pumps typically run on AC (alternating current) and require 230 volts of AC 1 phase electricity.
  • However, there are also options for wind, water, solar, and hydraulic powered well pumps, which can be useful in off-grid or remote locations.

Pump Type

  • Submersible pumps are the most common type of well pump, as they are installed directly in the well and can handle deeper water tables.
  • Jet pumps are another option, but they are typically used for shallower wells and have a lower maximum depth capacity.

Pump Capacity

  • The pump capacity should be matched to the well’s flow rate and the desired pressure range.
  • Oversized pumps can result in excessive cycling and premature wear, while undersized pumps may not be able to meet the system’s water demand.

Maintenance and Troubleshooting

Regular maintenance and monitoring of the deep well pump pressure tank and well pump are essential for ensuring optimal performance and longevity of the system. Some key maintenance tasks include:

  • Checking the pressure tank’s air charge and adjusting it as needed
  • Inspecting the tank for any signs of corrosion or damage
  • Monitoring the well pump’s performance and addressing any issues promptly
  • Regularly cleaning the pressure tank and well pump to prevent buildup of sediment or debris

By following these best practices and understanding the technical details of deep well pump pressure tanks, you can ensure a reliable and efficient water supply for your home or property.

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