Choosing the Right Ball Valve for Your Cold Water Tank: A Comprehensive Guide

As a facilities manager, ensuring the efficient operation of your building's water systems is paramount. Selecting the appropriate ball valve for your cold water storage tanks is crucial for maintaining optimal performance and compliance with water regulations. This guide explores various types of ball valves, including equilibrium straight arm, equilibrium drop arm, and several models from Keraflo's Aylesbury range, to help you make informed decisions tailored to your facility's needs.​

Understanding Ball Valves in Cold Water Systems

Ball valves play a vital role in controlling the flow of water into storage tanks. They operate by opening or closing a spherical closure unit (the "ball") to regulate water entry, thereby maintaining desired water levels and preventing overflows.​

Importance of Selecting the Right Ball Valve

Choosing the correct ball valve ensures:​

• Efficient Water Flow: Maintains consistent water pressure and flow rates.​

• Regulatory Compliance: Meets standards such as the Water Supply (Water Fittings) Regulations.​

• System Longevity: Reduces wear and tear on system components, extending operational life.​

Types of Ball Valves for Cold Water Tanks

Various ball valves are designed to cater to specific applications within cold water systems. Below is an overview of key types:​

Equilibrium Straight Arm Ball Valves

Equilibrium straight arm ball valves are engineered to self-compensate for changes in water supply pressure, ensuring a steady flow rate. They feature a straight arm connected to a float that rises and falls with the water level, directly controlling the valve mechanism.​

Main Features:

• Pressure Compensation: Automatically adjusts to variations in supply pressure.​

• High Flow Rates: Capable of handling substantial water flow, suitable for large tanks.​

• Durable Construction: Typically made from robust materials like gunmetal or brass.​

Applications:

• Large Cold Water Storage Tanks: Ideal for facilities requiring significant water reserves.​

• Systems with Variable Pressure: Effective in environments where water pressure fluctuates.​

Equilibrium Drop Arm Ball Valves

Equilibrium drop arm ball valves function similarly to their straight arm counterparts but incorporate a drop arm design. This design allows the valve to be fitted into raised float valve housings, facilitating compliance with air gap requirements necessary for preventing backflow.​

Main Features:

• Drop Arm Design: Enables installation in tanks with raised valve chambers.​

• Backflow Prevention: Assists in maintaining required air gaps to prevent contamination.​

• High Flow Capacity: Suitable for applications demanding substantial water flow.​

Applications:

• Tanks with Raised Valve Chambers: Common in systems requiring specific air gap configurations.​

• Category 5 Water Systems: Suitable where backflow prevention is critical, such as in healthcare facilities.

Keraflo Aylesbury K-Type Float Valves

The Aylesbury K-Type from Keraflo is a delayed action float valve designed to provide a full bore flow until the set water level is achieved, at which point it rapidly shuts off. This mechanism reduces water hammer and promotes efficient tank filling.​

Main Features:

• Delayed Action Mechanism: Ensures full flow until the desired level is reached, then closes swiftly.​

• Up and Over Discharge: Facilitates compliance with air gap requirements.​K

• Maintenance-Free Design: Constructed for long-term operation without the need for regular maintenance.​

Applications:

• General Cold Water Storage: Suitable for a wide range of facilities requiring reliable water level control.​

• Systems Prone to Water Hammer: Effective in mitigating issues related to sudden pressure changes.​

Keraflo Aylesbury KAX-Type Float Valves

The KAX-Type valve mirrors the operation of the K-Type but features an extended drop, making it suitable for tanks with raised valve chambers. This design is particularly beneficial for achieving the necessary air gaps in compliance with water regulations.​

Main Features:

• Extended Drop Design: Allows installation in tanks with elevated valve chambers.

• Delayed Action Filling: Provides full flow until the set level, then closes promptly.​

• Compliance with Air Gap Standards: Assists in meeting Type AA and AB air gap requirements.​

Applications:

• Tanks with Raised Valve Chambers: Ideal for installations where the valve needs to be positioned above the tank lid.​

• Facilities with Stringent Backflow Prevention Needs: Such as laboratories or healthcare institutions.​

Keraflo Aylesbury KB-Type Float Valves

The KB-Type valve offers a fully variable delayed action, featuring a chain-operated mechanism instead of a rigid float arm. This design allows for virtually unlimited opening and closing levels, providing flexibility in water level management.​

Main Features:

• Variable Delayed Action: Enables precise control over water levels with adjustable opening and closing differentials.

• Chain Operated Mechanism: Allows for significant drops from the valve to the water level.​

• High Flow Rates: Capable of handling large volumes of water efficiently.​

Applications:

• Pumped Systems: Ideal for use in systems where pumps control water delivery.​

• Industrial Tanks and Reservoirs: Suitable for large-scale water storage solutions.​

Keraflo Aylesbury KP-Type Float Valve Kits

Main Features:

• In-line Control Valve with Pilot Valve: Offers precise, remote control of water levels within the tank.

• Fully Variable Delayed Action: Like the KB type, you can tailor both the open and close positions based on your system’s needs.

• Flexible Installation: Suitable for tanks with or without raised chambers.

Applications:

• Complex Systems: Ideal for large commercial or industrial setups where exact water levels are critical.

• Dual-Tank Systems: Perfect when you’re synchronising water levels between tanks or operating with booster sets.

How to Choose the Right Valve for Your Cold Water Tank

With all these excellent options, selecting the right ball valve depends on several key factors related to your site, water usage, and compliance needs.

Consider These Before Deciding:

• Do You Have a Raised Valve Chamber?

If yes, you’ll likely need a Drop Arm or KAX-type valve to ensure an appropriate air gap is maintained.

• Do You Need High Flow Rates?

For rapid filling or large storage tanks, consider equilibrium valves, K-type, or KB-type options that can handle the demand.

• Are You Operating Under Strict Backflow Prevention Rules?

If your system is classified as Category 5 or needs a Type AB air gap, Keraflo's KAX or KP ranges will offer peace of mind and compliance.

• Do You Need Adjustable Water Levels?

The KB-type and KP-type valves offer full flexibility for precise control, great for pumped or highly controlled environments.

Final Thoughts: Tailoring the Right Valve to Your Facility

Ball valves may seem like small components, but they play a huge role in maintaining water hygiene, system reliability, and regulatory compliance. Whether you're running a school, healthcare facility, commercial block, or industrial plant, the right valve will:

• Improve filling efficiency

• Prevent overflow and backflow

• Reduce maintenance issues

• Help you stay compliant with UK water fittings regulations

At Titan Mechanical Services, we’ve helped dozens of facilities upgrade outdated ball valves and float systems, often unlocking significant improvements in water performance and regulatory compliance. If you’re unsure what valve is right for your system, our experienced team is happy to assess your tank setup and advise on the most suitable options.

If you would like more information about the Keraflo products we have featured in this article, then their website is one we would highly recommend.... Keraflo - Float Valves for Commercial Cold Water Storage Tanks