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Clogged and Corroded Hot Water Line

:(I have no hot water today. Please Help. I opened the inspection port fore of the circulating pump and there is plenty of water from the tank but its not getting to any of the fixtures in the house. Upon inspection there was a lot of build-up just inside the inspection port and cap. Is there a way to clean out the line or do I have to replace the entire water line? Is this a job for the Do-It-Yourselfer or a job for Professionals? How can I get my hot water back?

Re: Clogged and Corroded Hot Water Line

If your pipes are galvanized steel (grey in color) then count your blessings and replace as much pipe as you can see. Galvanized pipes last about 30 years and fail at the HWH first. They corrode from the inside out, much like the plaque in my arteries. You can't see anything wrong from the outside until one day the pipe explodes and hot water gushes everywhere. Copper would be an ideal replacement choice.

Re: Clogged and Corroded Hot Water Line

:(The water pipes are copper. I've been flushing my water tank for about 3 hours. I'd fill it up and run it out and fill it again. There are large pieces of debris settling in the bottom of the catch bucket. I disconnected the cold water supply line to empty the tank and now I have to deal with the air in the water line as well as clean the faucet screens. I still don't have any hot water.

Re: Clogged and Corroded Hot Water Line


You might find it easier to replace the HWH. OR;

1- if electric - pull out noth anodes (heating elements) and inspect. If crusty, then replace
2- if gas, keep flushing. You might find it faster to remove the HWH outside, pull the bottom valve and flush by adding water to the Hot water outlet side at the top while the valve is off at the bottom. Those cheap plastic valves have tiny openings inside.
3- If the tank is too much of a PITA to move and the flushing seems to be endless, try rocking the tank to loosen some of the crud at the bottom.
4- Add a sediment filter to your whole house water system.

Edit - if by flushing you mean just running the hot water at some tap, that will not make nearly as much of a difference as opening the valve at the bottom of the tank or removing it as mentioned above.

Re: Clogged and Corroded Hot Water Line

Without knowing the age and the type of your water heater, I would say repace it, it's beyond cleaning. It shouldn't take 3 hour or more to drain a water heater.

If you haven't replaced a water heater before, now it's not the time to learn how to do it. Call a plumber. Make sure he flushes all your faucets.

Re: Clogged and Corroded Hot Water Line

I usually do mine (electric) once a year. I shut unit off at the breaker or fusebox, shut off the hot water out and cold water in at the unit, connect a hose to the unit and drain it down while turning the cold water back on. Usually it's pretty rusty but the town of East Bridgewater in MA. has since changed out the Main so it's not that bad anymore. Before turning your breaker back on make sure the unit is full or you could do it damage.

Re: Clogged and Corroded Hot Water Line

Gentlemen, thanks for the advice. I'll try to clear up a few items for you.

1: The HWH is gas and I have received a manual from the manufacture, A.O. Smith, Promax Plus High Efficiency with a build date of 2005.
2: The tank is a PITA to move because of the earthquake straps and the permanently mounted cartridge circulating pump (Taco mod. #006-BC4) at the bottom drain.
3: I flushed out the tank and water system completely 3 times through the bottom drain and filled the tank after each draining. I turned off the gas before I even cracked the drain valve. I ran a hose out to a 5 gal. bucket so that I could see the sediments that were flushing out of the HWH, there's a lot. I then concentrated on getting the heavy seds. out of the tank by filling and flushing simultaneously and there are still some heavy seds. in the tank.

4: It seems that the 1/2 inch feed line to the recirculating pump is partially clogged. I opened the inspection port between the two ball valves in the recirculating line and the pressure from the tank side (3/4 in. supply) is far greater than the return side (1/2 in. supply).

5: I'm not getting anything that looks like rust, its lime deposits and some other form of corroded debris.

Ok, there it is. If I replace the HWH I have to cut the piping at the bottom drain. Then I have to remove the dry wall behind the HWH so that I can get at the return line and replace the clogged copper piping in the wall cavity. I did receive a bulletin from the HWH manufacture that said "deliming" is an option to remove the deposits and also suggested installing a filter system in the water line, which creates another problem. I'll have to find a place inside the garage where I can put the filter and to open the wall for access to the incoming water line.:(

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