Heating & Air Con

Will Chemicals Harm My Pool Heater?

Chemicals are an important part of managing a swimming pool – they help keep the water clean, protect the swimmers from sickness, and help keep the pool looking alive and healthy, rather than stained, or green with algae. But can those same chemicals harm the pool heater? It depends on the type of heater.

Pool HeaterAccording to, the newer models of pool heaters are less susceptible to damage from the pool chemicals, in particular an imbalance of the water chemistry. But older models of heaters have copper parts that might be damaged by pool acidity. So it’s not the chemicals used to balance the water that can cause the damage – it’s an imbalance in the chemicals in the water – there’s the real problem.

Acidity and the effects on a pool heater. When the levels of pH and alkaline are low, the acid might react with the copper in an older pool heater, leaching minerals and metals into the pool. It is noticed first as discoloration on the liner, pool grates and other pool equipment. At first, the effect will look like yellow or rust colored stains; later the heavy mineral deposits will bring on a violet discoloration. These effects will cause a damaged heater to leak. If the problem goes on long enough, the heater may need replacement.

Even while the heater isn’t used? It’s summer, and the pool is alive with swimmers on a daily basis. The water is nice and warm, and the pool heater hasn’t been turned on in months. But all of the water circulating through the pool passes through the housing between the pump and the pool, and get inside the pool heater, causing the problems described from an imbalance of pH and alkaline.

What are the acceptable ranges? For pH – it is best to maintain the level between 7.4 and 7.6. Otherwise the imbalance can corrode equipment like the pool heater, create stains on pool surfaces, and alter the interaction of other chemicals in the water. The alkalinity and calcium hardness are significant factors in scale deposits and corrosion, and weigh in heavily in the proper care of the pool heater and other equipment. The water alkalinity should be between 50 and 125 ppm (parts per million). Calcium hardness should stay between 200 and 500 ppm.

For the pool owner who doesn’t want damage to the pool heater, the first determination is if the heater is the older type which has copper parts – if so, the chemicals used to protect the pool will not harm the heater – but not using chemicals when the pH and alkalinity are out of balance can greatly impact the heater. Eventually, if left untreated, corrosive damage could mean replacement of the heater is required. This issue is less impactful for newer model pool heaters, but it is still important to maintains the proper pool chemistry to avoid problems.

If the pool owner has properly maintained the chemicals in his pool, he can relax and watch the fall football games, knowing that his pool heater isn’t being negatively affected by the pool water.

Katherine Estrada uses her skills from creative writing courses in college to develop new articles for When she’s not shopping at the mall with her friends, she experiments with writing poetry, or playing with her wonderful cat Pooh Bear.

November 8, 2013