Heating water leads to its expansion and increase in volume. In closed loop systems, water is non-compressible and an incredible amount of pressure leads to thermal expansion. This ultimately increases an enormous amount of pressure on the entire piping and other components of the water system. If not attended well, it would result in disruption and leakage of the entire piping.
In this case we need a set up that can provide additional space for the expanded water to flow and get relieved in the system; hence, the need for expansion tank. If we donot use this alternative then we would have to release the pressure of the system which would lead to energy wastage, decrease in the life of the system and cause safety hazard to the system.
Selection of tanks depends on its usage and needs of the system. They could be used for domestic purpose or for industrial and commercial use.
How to choose the right size for expansion tanks-
Before you purchase an expansion tank ensure you decide the exact requirement. This decision is based purely on 2 factors.
• Capacity of the boiler or a water heater in gallons
• Pressure of water in your piping system.
All this information will be available on the system or on the label provided by the factory. Also, plumbing information could be available with a local company supplying water.
For systems that are radiant and have hydronic applications, pressure usually never goes beyond 30 psi.
If you purchase an a tank which is smaller in size as required, extra pressure from the expanding and boiling hot water will lead to discharge from the valve.
However having an expansion tank which is bigger or larger in size from what is required there will not be any difficulty. Infact if we aren’t sure of the size, it’s safest to buy a one which is larger than what is required, so that it can accommodate the system safely. This should be a common practice. It’s advisable to oversize than to undersize.
Types of Tanks in the Market:
1. There are various plumbing applications available in the market. You can find tanks that are ideal for domestic purposes and are made with material which is non-ferrous in nature. Its best suited for heat exchange expansions. They help in securing fixtures and heaters and helps in eliminating energy waste and water. It reduces risk of pressure building and assures relief valve remaining intact.
2. There are many hydrogen heating applications as well which has more commercial and industrial use. These expansion tanks mainly separated air from water in the system and this acts as a permanent solution. Water pressure of the system is mainly controlled and normalised by the tank. The best characteristics of this tank are the ability to be installed is very simple.
3. You can also find tanks that will not need a fill-valve which is separate and automatic.
4. Some tanks mainly designed for snow melting applications. They can work in close and open loops systems. They are designed specifically for radiant systems that are highly efficient.
Hence we saw it’s not difficult to choose an expansion tank wherein we need to hire a specialist for this purpose. All we need is to understand the usage and the need along with the characteristics of different expansion tanks and buy the best that suits our purpose.
Author provides patented technology for Heat Exchanger Expansion Technology and Boiler Generating Bank Re-tubing.