Corroding Coil Problem May Be Addressed

Corroding Coil Problem May Be Addressed Council considers asking company to put in additive

Fast Facts Hot water furnace coils in Gardner have become corroded at high rates  Problem attributed to soft water (lack of minerals) and coil designs  additive would allow minerals to coat surfaces such as the coils Andrew Mansfield Reporter GARDNER The wallet-busting cost of prematurely replacing coils in hot water furnaces has been a nagging headache for residents and the city for several years. The city is hoping an adjustment to the water supply will be a solution to the problem of eroding, leaking pipes that has plagued some residents with flooding and caused a long-held search for what’s wrong. “There are a lot of rumblings in the city about this issue. It’s been going on for quite a while,” said City Councilor Scott Graves. Graves is chairman of the Public Service Committee and he brought forth the topic during its meeting this week. City Engineer Robert Hank­inson updated the committee that the city is closing in on asking United Water, the company that handles the city’s water distribution, to coat the pumps that carry Crystal Lake water with orthophosphates, a corrosion inhibitor. “I would think it’s imminent,” he said. Hankinson said on average, the issue of small leaks in the copper coils of furnaces has affected 200 out of the 8,000 homes in the city per year, with a replacement cost of $300 or more. “Statistically, it’s a small occurrence, but is not a small occurrence for the homeowner,” he said. “You can call it small all you want, I call it big. We do have an issue, whether it’s small or big or medium,” said Graves, adding that furnace companies do not insure anymore because of the faulty coils. After the city commissioned three studies looking at the problem, with the first two not producing answers, Hankinson said the most recent study concluded the city has a “natural occurring, very soft water from Crystal Lake.” The study was conducted by Corrosion Testing Laboratories in Delaware. After the results were learned, the city asked United Water to analyze the possibility of adding chemicals to samples of water to make it harder. By saying the city’s water is “soft,” Hankinson means the water lacks minerals, which he said generally people regard as a good thing because soft water tastes better and is easier to shower with. The city’s water does meet the standards of the Environmental Protection Agency. However, he also provided the example that distilled water would be corrosive to materials such as the copper coils in question as the water lacks minerals such as calcium. That is because minerals from water leave deposits, which is a good thing in the case of copper coils as those deposits form a coating that can limit corrosion that would naturally occur over time. So, if the city adds orthophosphates to the water, the hope is that the water can become less soft and alleviate the issue. That being said, there is no guarantee this change would make the problem go away. The most recent study Hankinson referred to also concluded that the shape of the coils in question, which are manufactured by the Watertown-based company Thermaflow/Everhot, might be a cause of the problem too. The study looked at three coils and found a small pocket area in them that causes water to whirlpool as it passes over, which can cause more erosion than would happen on a completely even, smooth surface. Conservation Agent Jeff Legros said some furnace companies have switched to using nickel for its coils instead of copper, with better results but at a more expensive cost for the consumer. But on the city’s end, all that can be controlled is the response to the water supply. “It’s very difficult to pinpoint what the issue is,” said Hankinson, giving an example that one neighbor could have multiple issues with coils, while another neighbor could have no issues for 20 years. He estimated that the cost for the city to add orthophosphates to the water supply would be in the $20,000 to $40,000 range, which would come from the water enterprise fund, a self-sustaining account that raises money through water rates. He said he did not think that level of cost would necessitate a need to raise rates. Since the money would come from the enterprise fund, the expense would not be a money order that needs to come from the city budget and be approved by the City Council. One key consideration for the city in making the move was whether or not to make the water “harder” for all residents, even if it is a slight and relatively affordable change, for the sake of a minority of residents. Hankinson said the city is waiting for final approval from the Massachusetts Department of Environmental Protection before it can ask United Water to add orthophosphates to the water. “Even though the city feels we’re not doing anything wrong, we’re doing some measures trying to make it stop,” he said.