[ddarsie]

In master bath tub the hot water has started to produce black particles, looks like sort of like black dust. No other faucet in house does this, and only the hot tap produces these particles and not the cold side. Any thoughts what could be doing this?

This is occurring in our rental place outside of Norfilk Va, 8 hours away. We're about to call a plumber in to take a look, but was hoping I might get some ideas here. Our only thought is a rotting valve.

Denis

 

[DannyT]

is the tub closest to the water heater?. has the water heater been flushed lately?

 

[Ishmael]

DannyT is correct. Manufacturers typically recommend that a hot water tank be drained/flushed-out annually to prevent the build-up of scale and sediment inside the tank. The reason the tub is more of a problem than any other fixture is that, most likely, there's no aerator or screen of any kind on the tub spout like there (probably) is on every faucet and shower head in the house.

 

[ddarsie]

Thanks guys for the quick replies.
No, the MBR bathroom is perhaps furthest from hot water heater.

I doubt the tanks has ever been flushed in its 7 year life. Because of the install location (3rd floor furnace room) I don't believe there is a full drain up there, only one of those plastic pans. I do not remember if there is a drain attached to it. I may ask tenant if he'd check it out.

I believe the faucet is a 2 control type (hot and cold have separate handles/valves). Given tenants description of the particles as "like black dust" I'm guessing it's most likely a gasket or ring in the hot water valve. I'm not thinking the lack of a strainer can explain this symptom.

Any further thoughts? Of course our biggest problem is being remote from the site (8 hour drive) so I'm limited re what I can ask a tenant to do (i believe he is fairly handy and willing).

 

[tylernt]

most likely, there's no aerator or screen of any kind on the tub spout

That, and the tub draws a lot more hot water, which causes the dip tube to stir up the sediment more energetically vs smaller fixtures.

a hot water tank be drained/flushed-out annually to prevent the build-up of scale and sediment inside the tank.

Flushed, yes. Drained, no. When draining, the sediment just sits on the bottom because the outlet for the drain is slightly above the bottom of the tank. Flushing allows the rush of cold water coming in from the dip tube to stir up the sediment, so more of it can float around and have a better shot at being pushed out the drain.

I guess you could drain and then flush, but it doesn't seem worth the extra effort IMHO.

Anyway, I like to flush in the spring or fall so I can run a hose out a window or door without the A/C or furnace working overtime. I run the hose to a concrete patio/walk/driveway and just let 'er rip until I stop seeing chunks shoot across the concrete.

BTW you should pull the little lever on the T&P valve at the same time to make sure it's not frozen.

I believe the faucet is a 2 control type (hot and cold have separate handles/valves). Given tenants description of the particles as "like black dust" I'm guessing it's most likely a gasket or ring in the hot water valve. I'm not thinking the lack of a strainer can explain this symptom

If it was a failing washer, wouldn't the faucet drip when shut off? A little washer can only make a few specks before it's all gone.

I doubt the tanks has ever been flushed in its 7 year life.

Ouch, most water heaters have only a 6 year warranty, and that's if it is flushed regularly. You might be looking at a new water heater soon...

 

[joecaption]

Activated Charcoal filter in the water system?

 

[ddarsie]

Hey guys back again. Had a plumber look at tub faucet. He believes there is no real problem and attributes black specks to prolonged non-use - he's assuming the non-use since we have no idea how much previous tenants used the tub. So he says just run water through faucet and let the dirt dissipate over a week or so.
I don't buy it. Current new tenant says there is less black stuff, but it came back somewhat a day later.
I'm betting you guys are right and the problem is tank sediment. Just what is the difference between a drain and a flush? Searching internet they seem to call flushing a tank what I would call a drain. Is the difference simply leaving the cold water input ON during the drain process or something? I want to get another plumber or handyman in there to do a flush. It would be good if I knew the difference so I could be clear what I was asking them to do.
\
Thanks,
Denis

 

[tylernt]

Flushing is as you say, leaving the cold supply on and opening the tap at the bottom of the tank.

Draining would be shutting off the cold supply, opening a hot tap somewhere to let air into the tank, then opening the tap on the bottom of the tank.

As I mentioned before, draining is pretty useless unless followed by a flush.