Water is sometimes heated and cooled inside the pipes, which can create thermal expansion. If ignored, it might result in damage and possibly system collapse. Likewise, to prevent them from happening, plumbers suggest two tools, a relief valve or an expansion tank.
So what is the main difference between a thermal expansion relief valve and expansion tank? The main difference is that thermal valves relieve excess pressure, while expansion tanks absorb and store excess water volume.
The features, benefits, drawbacks, and differences between these two systems will all be thoroughly compared in this article. You may choose the option that is most appropriate for your particular plumbing system. Let’s get started.
What Is A Thermal Expansion Relief Valve (TERV)?
The expansion relief valve is a device installed on a plumbing system to alleviate pressure induced by thermal expansion within the pipes. These devices are often put on the water heater’s cold water supply line or the supply line for water close to the main cutoff valve.
Types Of Expansion Valves
TERVs come in mechanical and electrical varieties. Electronic TERVs employ sensors to detect pressure changes and trigger a solenoid valve to release excess pressure. Mechanical TERVs function through a spring-loaded valve that opens when the system pressure exceeds the specified limit.
How It Works
The expansion of hot water causes pressure to build up in the plumbing system. By sending extra water down a drain or another specified area, TERVs avoid the building of excessive pressure. By doing this, the pressure is reduced and system damage is avoided.
Advantages And Disadvantages Of Expansion Valves
TERVs have the benefits of being inexpensive, simple to install, and requiring little maintenance. They are also good at limiting thermal expansion and avoiding plumbing system harm.
But periodically, TERVs might break down or become trapped in the open position, wasting water and raising utility costs. They also ignore the problem of water hammer, which can still exist even with a TERV fitted.
What Is An Expansion Tank?
An expansion tank is a plumbing system accessory intended to manage thermal expansion and water hammer. They are often mounted on the supply line close to the main cutoff valve or next to the water heater.
Expansion Tank Types
Bladder-type and diaphragm-type expansion tanks are two of the most commonly found tanks. While diaphragm-type tanks employ a flexible membrane to divide the water and air chambers, bladder-type expansion tanks use a rubber bladder.
While diaphragm-type tanks are more typically utilized in commercial systems, bladder-type tanks are more prevalent in residential applications.
How It Works
Water pours into the expansion tank as it heats up and expands, compressing any gas or air within. Because of its compressibility, water may expand without raising the pressure in the plumbing system. Compressed air or gas forces the cooling, contracting water back into the plumbing system.
Learn more from this video:
Advantages And Disadvantages Of Expansion Tanks
These are flexible options for plumbing systems of various sizes since they are very successful in handling both thermal expansion and water hammers. They also require little care and have a long lifespan.
However, they can be more difficult to install and are more costly than TERVs. To guarantee optimal operation, they also need routine pressure checks and air/gas recharges.
Thermal Expansion Relief Valves and Expansion Tanks: Differences
TERV and expansion tanks are the two basic solutions to the thermal expansion issue. Let’s see some differences between these two systems:
Expansion valves are a common choice for low-budget people since they are often less expensive than most expansion tanks. Although TERVs are less expensive, initially, they may end up costing more in the long term owing to probable problems and higher water costs.
And the expansion tank is more expensive initially than TERVs. But in the long run, they are more cost-effective since they need less maintenance and have a longer lifespan.
TERVs don’t need additional plumbing or space and are quite simple to install. They normally take less than an hour to install and are attached directly to the current plumbing system.
Whereas, the expansion tank is more difficult to install since they need more room and piping. To guarantee optimal operation, they also need recurring pressure checks and air/gas recharges.
Due to its lack of moving components and lack of air/gas recharging, TERVs require less maintenance. They can, however, break down or become trapped in the open position, wasting water and raising utility costs.
However, for effective operation, expansion tanks need regular pressure checks and air/gas recharges. In contrast to TERVs, they last longer and require less maintenance overall.
Effectiveness In Controlling Thermal Expansion
Thermal expansion can be effectively controlled using TERVs and expansion tanks. The tanks are often more efficient since they allow the water to expand, lowering the pressure inside the plumbing system.
Compatibility With Different Plumbing Systems
TERVs are best suited for smaller systems with low to moderate thermal expansion. While an expansion tank is appropriate for systems with moderate to high thermal expansion and water hammer.
When To Use An Expansion Valve Vs An Expansion Tank?
Let’s see what we should know when considering an expansion relief valve vs an expansion tank:
Factors To Consider When Selecting Between The Two
- The extent of thermal expansion and water hammer
- The size and complexity of the plumbing system
- And financial limitations should all be taken into account when deciding between a TERV and an expansion tank.
Where Each Device Is More Appropriate
Smaller domestic plumbing systems with minimal to moderate thermal expansion can use TERVs. While larger residential and commercial ones with moderate to high thermal expansion and water hammers are suited for expansion tanks.
Benefits Of Consulting A Professional Plumber For Assistance
A professional plumber should be consulted when deciding between a TERV and an expansion tank. It’s because they can assess the particular requirements of your plumbing system and offer professional advice on the most suitable equipment.
Now we shall see some related questions you might have regarding them.
Water heating causes pipes to expand and gain volume, leading to thermal expansion in the system. The pipes may experience pressure as a result, which might result in leaks or other damage.
Installation of expansion tanks is more difficult than that of TERVs since it calls for more piping and space. Hence, to guarantee appropriate operation, it is advised to consult a qualified plumber before installing.
Yes, a malfunctioning TERV or expansion tank can cause damage to your plumbing system, leading to leaks, water waste, and increased utility bills. Regular maintenance and monitoring of your plumbing system are crucial to prevent issues related to thermal expansion.
When comparing thermal expansion relief valve vs expansion tank, they are both effective solutions for moderating thermal expansion. Moreover, preventing damage to plumbing lines. The particular requirements of your plumbing system will determine whether to use a TERV or an expansion tank.
So, to make sure the best equipment is chosen, it is advised to consult a qualified plumber. Regular maintenance and monitoring of your plumbing system are crucial in preventing issues related to thermal expansion.