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Plumbing in the Home/Electric Water Heater Knocking


Hi Jay - We have a tall, 11 year old Lochinvar electric hot water heater that was putting out brown hot water for at least one year. We finally got around to asking a plumber to take a look at it. He told us that it would need to be replaced and it would cost us around $2,000-$2,500. We're in Connecticut.

I researched this on the Internet and decided instead to ask him to flush the heater. I watched him do this with a pail rather than a hose? Which didn't seem right to me. And, it took a very long time. Finally, the water did run clear. But, as soon as he left, we noticed that the heater now knocks loudly sometimes. But, not all the time. I am trying now to keep track of exactly when it knocks.

My question is - can this be fixed or should we purchase a new water heater. We know nothing about fixing water heaters.

Cindy, what's going on here is the tank has sediment for the minerals that settle out of the water and accumulate on the bottom of the tank. It is very difficult to remove this sediment and not worth the cost.   When the lower element heats up, if it is surrounded by the sediment, it will pop or percolate as we call it.Brown water can be caused be rusting of the tank or iron in the water. Iron shows up in color ranging from bright orange to a pale brown.
I have been installing water heaters since 1975 and I have customers that flush the tank religiously and others, myself included, that never touch the heater once installed. I have never seen a correlation that proves flushing extended the life of the heater. Changing the anode rod can help but again, not worth the cost.
Now, speaking of cost... Your plumber is way out of line. An average install with the tank and parts included should be under a thousand dollars. Around here we get 650 t0 8 hundred depending on the existing conditions. The dealer cost on a residential 40 gal. tank is approx. 400. in upstate NY


Plumbing in the Home

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Jay Nicholas


Plumbing & Heating (warm air, hot water & steam heat)


40 years in the business, 40 years as a lic. master plumber in NY State. Retired

Graduated Magna cum laude at the School of Hard Knocks

Past/Present Clients
Commercial, residential and light industrial. You name it ...I have probably worked on it

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