clogged gunky faucet after pipe-freezing episode

[RustyShackleford]

We just came up to our mountain house and discovered that some pipes had frozen and burst. (There's a back-story and another question below). Being thankful that I know how to do plumbing, and that I had some spare parts lying around from other work (mostly push-to-connect fittings), I was easily able to restore cold water, and will do the hot tomorrow after getting a couple things at Lowe's. So far all good, except for one thing.

When we turned on one of the cold water faucets, it coughed up some dark grey crud and then stopped pretty much completely. The faucet worked fine before all this. Our water is pretty clean as far as sediment and such, but does contain some town-added sanitizing chemicals, so I've definitely seen some corrosion. It's a bit hard for me to fathom how the freezing pipes caused this to come to a head, but if anyone has any idea, I'm all ears and full of thanks. At any rate, I guess I'll first disconnect the connector from the stop valve under the vanity, and try to narrow the stoppage down.

Back story: We realized the house was using WAY too much electricity when vacant, and the POCO quicly solved that, explaining that the baseboard heaters are not off when the thermostat knob is fully counter-clcokwise. You have to turn off the breakers for them. Duh. So the house got a lot colder than it had been. We've always drained the pipes when we leave the house in winter, but the hot water heater is in the basement, so our usual pipe-draining procedure doesn't drain those, and of course those are the ones that burst. I'm wondering, would it suffice to just drain a few gallons out of the water heater, so those pipes get emptied and the water heater has some expansion space (I don't think there are severe prolonged enough freezes here for the water heater contents to freeze solid).

 

[gthomas785]

Check the aerator on the faucet. I bet that's where most of the crud is and if you remove it you can flush the rest out. (Edit: anytime you do plumbing you will see some crud get disturbed. That's normal).

I'm from the North, so the idea of leaving any water in an unheated house does not feel good to me. What's the harm in just fully draining the water heater?

 

[Dieselhead]

Could be the expansion of the pipes loosened up some sediment that had attached itself to the sidewalls of the pipe.as mentioned the aerator caught it all and that’s the blockage.

 

[RustyShackleford]

Thanks all, I'll check it out tomorrow before I go to get the stuff to fix the pipes going into the water heater.

Sure, draining the whole water heater would be best, but would take a while. I think just enough to empty those pipes should suffice.

 

[Murray01]

Thanks all, I'll check it out tomorrow before I go to get the stuff to fix the pipes going into the water heater.

Sure, draining the whole water heater would be best, but would take a while. I think just enough to empty those pipes should suffice.

I wouldn’t risk leaving a hot water tank with any water in it during winter in an unheated building, that being said when we shut the cabin down for the winter it’s going to be real winter. When we drain the hot water tank it’s still draining when we drive away for the winter. One advantage of a yearly drain is all the sediment that collects in the tank is flushed.

 

[RustyShackleford]

I wouldn’t risk leaving a hot water tank with any water in it during winter in an unheated building, that being said when we shut the cabin down for the winter it’s going to be real winter. When we drain the hot water tank it’s still draining when we drive away for the winter. One advantage of a yearly drain is all the sediment that collects in the tank is flushed.

Yeah, I'm in central North Carolina, not CANADA I don't see it getting much colder here than the snap we just had that froze these pipes.

Which makes me wonder if the T&P relief valve would be a reasonable way to partially drain our hot water heater. Would eliminate the need to snake a hose out to lower grade - just dump it into a bucket and then down the nearby utility sink. Google AI says that's a bad idea though.

This water heater appears to be near the end of its lifetime. I believe when I replace it, I will built a stand to hold it 6-12" above the basement floor. Be much easier to drain from the proper faucet.

 

[RustyShackleford]

This water heater appears to be near the end of its lifetime. I believe when I replace it, I will built a stand to hold it 6-12" above the basement floor. Be much easier to drain from the proper faucet.

I went ahead and raised it. Since had to pretty much re-plumb it anyhow. There's a little fly in the ointment of draining (or partially draining) the water heater to drain those pipes that can't be emptied any other way: I put in a mixing valve, which contains, backflow preventers. So the water in the hot-water pipe will not drain. So I put a tee and a 1/2" valve just above the mixing valve. Plus both 3/4" lines coming up from the water heater are PEX now (with the requisite 18" of copper between the PEX and the water heater proper. So hopefully that'll suffice.

 

[Murray01]

Any evidence of the dark grey sludge on the pipes?

 

[gthomas785]

Do you have an air compressor? You can get an adapter that hooks to a 3/4 garden hose bib to blow the pipes out. That's what I do to winterize my barn plumbing. Also makes the water heater drain a lot faster if you pressurize it to 60 psi or so.

 

[RustyShackleford]

Any evidence of the dark grey sludge on the pipes?

Nope. Just pulled the faucet aerator and rinsed it out and it's fine. Didn't see any similar sludge in any of the water-heater piping.

 

[RustyShackleford]

Do you have an air compressor? You can get an adapter that hooks to a 3/4 garden hose bib to blow the pipes out. That's what I do to winterize my barn plumbing. Also makes the water heater drain a lot faster if you pressurize it to 60 psi or so.

Don't have a compressor up here. Not too worried. I think last month was about as cold as it gets around here, and only pipes that froze were the two coming from the basement ceiling down to the water heater. A little worried about that mixing valve that I can't totally drain (see post #7 above).

 

[Murray01]

Would some heat tape prevent freezing next cold snap? A just in case measure.

 

[EatenByLimestone]

how old is the system? I flushed my baseboard system and was shocked how much black nasty stuff came out. I’m not sure what it precipitated off of, or if it just fell out of suspension in the water. I’m also not sure if the baseboard heaters work better now.

When I winterize my cabin I drain everything I can. Water that isn’t there can’t freeze.

 

[RustyShackleford]

how old is the system?

As old as the house, about 25 years. After we bought it, 4 years ago, I noticed the water pressure was way too high, basically equal to the 100psi or so coming in from the gravity fed town system. When I took the pressure regulator apart, it was badly corroded, but nothing like the black stuff in this faucet's aerator.

When I winterize my cabin I drain everything I can. Water that isn’t there can’t freeze.

Probably is, family goes up there in winter, so don't wanna make it too complicated. Since I had to re-plumb the water heater, I raised it, in a plastic pan on cinderblocks. So easy to drain enough to. empty those pipes, nothwithstanding also needing to separately drain the pipe above the hot water mixing valve. But now, they need to be sure to fill the water heater up as soon as they power it on. Yikes. Maybe heat tape is the better solution.

 

[EatenByLimestone]

How about a setup where they can drain the WH into a sump pump through a hose already run from the drain valve?

1. Turn the water off
2. Turn off power to the WH
3. Open drain valve.
4. Open main system drain (cold water)
5. Open faucets upstairs to further drain the system.

It’s not that bad of a list.