Condensate Corrosion — the Hidden Cost of High Efficiency Appliances


Modern gas appliances such as furnaces, boilers, and water heaters are becoming more and more efficient, which is, of course, a great thing. There is one thing about high efficiency gas appliances that you may not be aware of: their production of condensation can severely damage appliance piping.

Older appliances didn’t create condensation because the flue gas was too hot for condensation to form. Modern appliances utilize more of the heat generated from the gas we burn: the exhaust gases are much cooler and, as they drop below the dew point, condensation forms. This in itself is not a problem. High efficiency furnaces and water heaters have drains for condensation. The problem is the acidity of the condensation.

Condensate formed from combustion gas is extremely acidic and therefore very corrosive. It can eat through copper piping in a matter of months and through cast iron drains in just a year or so.

Joan Z., resident of the Berkeley Hills, discovered this problem the hard way. A furnace installation from a few years previous had corroded the sewer lines under the slab in her basement and caused thousands of dollars in damage. Big Blue Plumbing had to excavate all the slab in the basement and replace the drain lines with upgraded HDPE plastic.

All that damage could’ve been avoided with a simple item: a condensate neutralizer. A condensate neutralizer removes acidity from condensation, preserving your piping—and protecting you from thousands of dollars in potential damage—for just a few hundred dollars.

Do you have a high efficiency furnace, boiler, or water heater?
Is it a condensing model?
Is the pipe the condensate drains through made of the appropriate materials?
If you have a condensate neutralizer, does it need replacing?

Big Blue can help you answer these questions.

Incidentally, ensuring proper condensate treatment is one of the many benefits of being in our maintenance program, The True Blue Club. Call (510) 939-7870 and see if the True Blue Club is right for you!