Published: March 31, 2017 - by Dr. Neil Watson & Tom Tonkins

Categories: Water Quality

Adey MagnaClean Micro2 Front

How has the use of high-efficiency boilers and circulators changed the field of hydronic heating?

High efficiency boilers and pumps have brought with them many positive changes – increased efficiency leads to reduced heating costs and lower carbon emissions, for example. However, also with the introduction of these products has come an increased need to maintain water quality to keep the systems operating efficiently, and to prevent failures. In fact, the efficiency of any hydronic heating system is ultimately dependent upon the water quality, and the total health of the system.


How would you define water quality in a hydronic system?

There are many components that make up “water quality” – including PH levels, water hardness, and levels of elements such as chloride, copper, and iron. One of the most important water quality issues is the presence of iron oxide, also known as magnetite. Iron oxide is an unavoidable result of oxidation in untreated systems with iron pipework — and it can cause major problems for several reasons.


Go on…what are the reasons that iron oxide is a main culprit?

High efficiency boilers feature narrower waterways than older models, which helps increase efficiency. If water quality is not properly maintained, these narrow waterways, as well as the heat exchanger, can be prone to blockage as magnetite collects and forms a sludge in areas of low flow. Also, if it combines with lime scale it forms a hard enamel-like coating, reducing pipe diameter.

Likewise, ECM (Electronically Commutated Motor) circulators can also suffer as a result of poor water quality, therefore reducing system efficiency. ECM pumps contain magnets that attract micron-size particles of magnetite that are highly abrasive and can cause damage to rotor mechanisms. Iron oxide particles can also accumulate here, just as they can in boilers, and eventually block the water flow through the pump.


What are some of the issues that can arise in hydronic systems exposed to poor-quality water, and how are they diagnosed?

Water quality is of tremendous importance to system health and efficiency. ADEY’s® experience shows that nearly 70% of circulator pumps returned to pump manufacturers fail due to mainly iron oxide build up. It only takes a small amount of iron oxide to foul a pump or block a waterway.

In the most severe cases, these types of issues can cause expensive damage to a system. Even in mild cases, however, this build up can lead to reductions in system efficiency, severely impairing equipment that was specifically designed to deliver high-efficiency operation. In turn, this leads to higher energy costs, higher maintenance costs from frequent breakdowns, and increased carbon emissions.

In many cases the first symptom that something is wrong is higher fuel bills for the homeowner. This can be as a result of reduced system efficiency — the boiler fails to deliver enough heat into the room, and the homeowner turns up the heat on the thermostat to compensate. In most cases, this is as a direct result of iron oxide sludge buildup.


What products or solutions are available to help improve water quality in these systems?

Improved water quality — in fact, total system health — should be the goal of any hydronic heating contractor. To that end, ADEY has introduced a family of products designed to address water quality issues. The heart of these products is a line of magnetic filters specifically engineered to remove virtually all iron oxide sludge from hydronic systems. Click here to learn more about ADEY products.


What else should contractors know about water quality in hydronic systems?

Water quality is not a one-time fix. It has to be checked and maintained, and it requires follow-up and proper care in order to achieve favorable results. The presence of iron oxide sludge within a heating system can significantly impair the performance of a corrosion inhibitor by using up the active ingredients. Therefore, a proper water treatment maintenance regime should include checking that the corrosion inhibitor is adequately dosed, and any collected iron oxide sludge is cleaned from the filter. This is usually performed on an annual basis, and can form part of a service contract.


*Pump failure data based on studies of returns to European pump manufacturers.