A short story: Just had a new natural gas hot water heater installed in the basement. I later smelled gas - they sent another plumber out to fix it. Joint/connector - whatever it's called - was not tight. Seems to be fixed because gas smell went away but I'm not certain they put goo on the threads or even if they are supposed to.

Next issue: A week later I was running the hot water in the kitchen. What looked like diluted blood ran from the faucet. Not really brown - it was reddish pinkish brown. Ran the water for a while - there were spits and spurts then finally turned whitish. There is somewhat of a mild chemical smell to the water now and an aftertaste when brushing our teeth. Also, the municipal water is hard water and I usually run the cold water for a few seconds until it goes from whitish to clear. Since the water heater was installed, both hot and cold water require I run it for a long time before it turns clear.

Should have added: Anyone know how to check if joint/connector done properly and what is causing red water?

The joints in a copper gas line are flare joints and the threads do not need pipe compound or to be Teflon taped.
The red water's caused by iron oxide, (rust) sorry I can't tell you where it's coming from. I would call the plumber that installed the heater back. Something's not right here. Good luck, Tom

Thanks for quick response. However, the gas line is cast iron not copper. Also, any idea why there is a smell and bad taste to both cold and hot all of a sudden?

p.s. hope the radiation treatments are almost over and that you'll soon get your energy back. Great news that you beat the C!!

The gas line is black iron and not cast iron. The threads will have to have pipe compound or Teflon tape on them. The gas line has nothing to do with the water coming out of your faucet. Have the water heater installation checked. Regards and let me know, Tom,