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Dumb mistake draining water pipes??

Hi folks. I was replacing the water shutoff valve to my toilet downstairs. I opened the sink faucets upstairs and downstairs to relieve the water pressure so the water wouldn't pour out while I'm working. But I forgot to close the valves to the two upstairs toilets, and eventually noticed that water was draining from those tanks into the lines. Yuk, I know the tank water is not the cleanest and don't want it showing up at the tap. I ran the water for awhile and hopefully none of it remains in the lines.

Is this really a concern? Should I be shutting off all the toilet valves when I need to drain the pipes of water? I've not seen it mentioned in do-it-yourself forums. Thanks.

Re: Dumb mistake draining water pipes??

As long as you ran the water for a little while afterward to flush the pipes of any sediment it's not a concern.

Probably more of a psychological thing than anything else.

After all the valves are normally open all the time and any nasties could migrate from the tank back into the water pipes if they wanted.

Yes, you should shut any "upstream" valves from your work to keep it from draining back to your work location.

Re: Dumb mistake draining water pipes??

To prevent this in the future, install ballcocks (fill valves) that feature anti-siphon technology.

Re: Dumb mistake draining water pipes??

first off, water from the tank can not go back into the water supply pipes. it's impossible. ideally, the way to drain all the pipes running to toilets on upper floors would be to shut off the water at the above toilet. disconnect the toilet supply pipe from the shut off valve. turn off the water main and open the fixtures in the basment and first floor, then go to the second floor and open those fixtures followed by the water shutoff to the toilet that you just disconnected.

also, the water in the back tank of the toilet is as clean as the water in the rest of the house. it's the water in the bowl that you don't want to drink. and it's 100% impossible for water from the bowl to get into your drinking supply.

Re: Dumb mistake draining water pipes??

for those reading along, be aware of the hot water tank when draining water lines. It is possible to siphon the water out of your hot water tank and damage the tank, particularly of it is an electric hot water heater. Always turn the pow-er off to electric tanks, and turn down the temperature on gas tanks before draining the lines.

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