I was recently tasked with determining which ball valve should be used to replace old ones in a barn. After looking at the different material options and knowing that they would connect to PVC pipe, there was no doubt I was looking for a PVC ball valve.
PVC ball valves can be divided into three different types, each with their own benefits. These three types are compact, union and CPVC. In this blog we will explore what sets each of these types apart and the benefits they each have.
Compact PVC Ball Valves
Compact PVC ball valves are constructed using the molded-in-place method defined in our construction methods blog. Using this unique method, molding the plastic around the ball and stem assembly, provides multiple benefits. A full port ball is used, but there are no seams in the valve from having to add it in from one end. This makes the valve stronger and more compact without obstructing the flow. Compact PVC ball valves are available in threaded IPS (Iron Pipe Size) and slip connections suitable for both Schedule 40 & 80 pipe.
Being a strong and rigid valve, they are ideal in a variety of water supply applications. When looking for an economical valve, a compact PVC ball valve is an excellent choice.
Union PVC Ball Valves
The union designs feature unions on one or both connections to allow in-line maintenance to the valve without having to disconnect it from the pipe. No special tools for maintenance are required as the handle has two square lugs that allow the handle to be used as a spanner wrench. When maintenance to the valve is required, the threaded retainer ring can be adjusted or removed using the handle to adjust the seal or replace the O-rings.
When the system is under pressure, a blocked union will prevent the ball from being pushed out once the union is taken apart, whereas an economy union does not have anything keeping the ball from being pushed out.
Did you know? Compact and union PVC ball valves can be used in both Schedule 40 and Schedule 80 systems as these ratings refer to the pipe wall thickness. PVC ball valves are rated based on pressure not wall thickness allowing them to work for both Schedule 40 and Schedule 80 pipe. The outside diameter of both pipes remains the same, it is the inside diameter that gets smaller as the wall thickness increases. Generally, Schedule 40 pipe is white and Schedule 80 pipe is grey but either color valve can be used in either system.
CPVC Ball Valves
CPVC (Chlorinated Polyvinyl Chloride) ball valves are constructed the same way as compact valves however there are two main differences; the temperature rating and the connections. CPVC ball valves are made using chlorinated PVC, allowing them to withstand higher temperatures. These valves are designed for hot water applications up to 180°F.
The connections on CPVC ball valves are CTS (Copper Tube Size) which is a much smaller pipe size than IPS. CTS is designed for both hot and cold water systems though it is mainly used in hot water lines.
CPVC ball valves have a beige color to help differentiate them from regular white compact ball valves. With their higher temperature rating, these valves are great for use in heating applications such as hot water heaters.
PVC ball valves are an excellent choice in a wide range of plumbing applications with different options for maintenance and high temperature. Ball valves are also available in Brass and Stainless Steel so there is a ball valve for every application where the flow of water needs to be controlled.
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