Characteristics of Ideal Water Heater Feedwater and Scale Remover
A water heater or boiler is a substantial investment, both in terms of initial installation costs and maintenance over the medium to long-term. Making sure that the right type of water is used with a boiler and carrying out preventative maintenance with descaler can help to substantially reduce faults and decrease running costs. This article explores the ideal characteristics of boiler feedwater and what to do if you get scale in your boiler.
Note: I use the term 'boiler' throughout the rest of this article; you can substitute the word 'water heater' if you prefer.
What is boiler feedwater?
Boiler feedwater is the water that comes from the mains supply and is then fed into a boiler and heated to provide hot water and other heating needs. There are certain desirable qualities in boiler feedwater that make it less likely to cause a problem with a boiler. These properties include:
- A high pH level
- A low mineral content
- A low amount of chloride
- Preferably no dissolved oxygen
Ideal boiler feedwater - A high pH level
A pH (acid/alkaline) measure of above 7-8 is ideal. This means that the feedwater is less acidic and consequently less likely to cause corrosion in the boiler.
Ideal boiler feedwater - A low mineral content
A low mineral content means that minerals are less likely to build up in the boiler due to evaporation. This type of deposit is known as scale and can cause faults in boilers and heating systems. Minerals that are likely to cause scale include magnesium, sulphates and calcium. Water with lots of minerals dissolved in it is known as 'hard water'.
Ideal boiler feedwater - A low amount of chloride
High chloride content can damage the boiler by attacking the metal inside it.
Ideal boiler feedwater - Preferably no dissolved oxygen
Dissolved oxygen can also damage the internal workings of a boiler over time.
Analyzing boiler feedwater
Boiler feedwater can be analyzed to find out about any minerals that are dissolved in it and any other possible issues. If problems are found, there are certain chemicals and processes that can be used on the water before it is fed into the boiler.
These processes can extend the life of the boiler and reduce long-term maintenance costs.
Explanation of boiler feedwater and its treatment
If a boiler is using water from a hard water area, scale is likely to occur in the boiler over time. As the water in the boiler heats up and evaporates, minerals such as silica and calcium are deposited on the pipes and other internal mechanisms of the boiler.
Deposits of scale can impact on efficient heat transfer and if left untreated will eventually cause faults in the boiler and heating system. Fortunately, this problem can be easily remedied through using boiler scale removal chemicals, known as 'descalers'.
Descalers are chemical compounds that dissolve the scale and get the boiler back into good working order.
A descaler can be added to a boiler by a plumber or heating engineer. They are then allowed to run through the system for a few days before being flushed out and fresh water being added. Alternatively, some descalers are designed to be added to a heating system permanently, protecting it over the long term.
Have you analyzed your boiler feedwater or had your boiler descaled?
The installation and maintenance costs of a boiler and heating system can be substantial. Using proper boiler feedwater and carrying out descaling if it is needed can help to reduce faults, increase efficiency and look after a boiler in the medium to long-term.