Brown Water in Hot Water GI Pipeline

Flush it to drain.

This probably iron or rust. It depends on the source.

If it was coming from the water source, it would be in both the hot and cold pipes, and a whole building iron removal system would do it.

Since it's only in the hot water, it indicates that the source is in the building. Start with the easiest, less costly solutions first.

Flush out hot water heater........turn off the heat source first! If you're lucky, it's just rust deposits in the bottom. This is something you should be doing at least yearly anyway.

Try that and get back to us. If that doesn't fix it, we'll go from there.

Note: If your hot water heater runs on natural gas or propane, and you are not familiar with the shut down and restart process, hire a professional! If it's electric, just find and turn off the breaker.

Well it depends on what you mean by brown water. If this is potable water that has become discolored from rust or other particulates then flushing the system should mediate your problem. If the particles are coming from your system's pipe walls then you may find that you have some pin hole leaks that will also need repair.

If instead you mean that some stupid resident thought they were a plumber and piped brown water into the heating water system, well now you have a real problem. Yuck.

Possibly your sacrificial electrode (Mg alloy) is qoing-gone and soon failures will follow. If so find and replace it before flushing. S.M.

First thing I'm going to ask is whether you're on a well or municipal water supply system. If you have a well, then it's entirely possible that the drawn water has moderate to high iron and manganese constituent levels. These are easily removed with the properly selected commercially available residential water treatment systems.

Also, I would suggest that you drain the hot water heater tank until the drain water runs clear (and then some...) at least every other month if you have well water with the aforementioned contaminants. Doing this will prolong the life of your hot water tank.

Cool Moody welcome to CR4. I am not sure what GI pipe means nor residential building. If this is a single family home on a private well, you should be doing a raw (untreated) water analysis to include major ions, metals (ask for total iron and total manganese as well as soluble iron and soluble manganese as well as a general metal scan), Turbidity, colour, pH, conductivity, alkalinity, TDS, pH of saturation. You should also have the accredited lab perform calculations for Langlier's Index at cold temperatures, ambient temperatures, and at the hot temperatures you would expect in a HWT. I would also recommend doing coliform, E. coli, and HPC bacterial counts on the raw water.

Once you have these results you should have information to discuss the results with a competent hydrogeologist or someone well versed in water treatment. They should understand groundwater microbiology and geo chemistry. I could try to explain all the problems here but it would take a lot more space and time. There was a similar question posted and titled " water pipe pitting" and can be found through a search of CR4.

If the water is municipal water, you may find answers by discussion with the local utility. They should have good chemistry and microbiology and the history of operation. Similarities between your question and the water pipe pitting exist and may provide some answers. Hot water has a lower level of saturation than cold water. The hot water tank can be filled with precipitated material and now working its way into your system. There remain several avenues of correction but more detail is needed. Others have posted some good answers at least in part. Sorry but more info is needed.