Brown tint to water with rust residue

[scubapete]

The kitchen cold tap and bath cold tap upstairs are both fed from mains. The last couple of days when we run a bath for our boy, the water has a brown tint and there is tiny rusty bits settled on the bottom of the bath.

After some experimentation this is what I've found:

- The bath cold tap is the source of the brown water
- The kitchen tap runs clear when the bath tap is OFF and runs the same brown when the bath tap is ON
- Hot taps run clear
- Heating F+E tank level is normal with no signs of overflow although lots of rusty powder settled at the bottom
- Water header tank is normal and water is clear
- Running bath tap for ten minutes does not clear the water

Any ideas? There can't possibly be a connection between the mains and the heating circuit right? Except through the hot tank and then the hot water would be affected?

Neighbours haven't noticed anything. Water board say nobody else in the area has called about this.

 

[seco services]

cold mains has no connection to the hw cylinder or the heating.
only to the ball valves in the two loft tanks.

 

[scubapete]

Thanks for confirming that.

But you don't get rust in copper pipes, right? And the pipe in the bathroom is plastic. Which leaves the old and probably lead mains pipe as the source of the rusty water. But then why does it not come out of the kitchen tap and only the bath tap?

 

[kevplumb]

lead dosent rust

 

[Agile]

What make and model of boiler do you have?

Tony

 

[scubapete]

Pretty old Potterton Netaheat. It's a standard gravity system with no mains feed to it.

 

[doitall]

Coil in cylinder gone or primatic cylinder.

 

[kevplumb]

primatic or coil gone wouldnt affect the mains cold

The kitchen cold tap and bath cold tap upstairs are both fed from mains. The last couple of days when we run a bath for our boy, the water has a brown tint and there is tiny rusty bits settled on the bottom of the bath.

After some experimentation this is what I've found:

- The bath cold tap is the source of the brown water
- The kitchen tap runs clear when the bath tap is OFF and runs the same brown when the bath tap is ON
- Hot taps run clear

 

[Agile]

The kitchen cold tap and bath cold tap upstairs are both fed from mains.

That would be very unusual !

Are you quite sure its plumbed like that?

So far from what you have said I cannot guess what going on.

Its certainle rather unusual but like all these situations when we know whats wrong it will all be obvious.

Has any changes been made to ANY plumbing or heating?

Tony

 

[doitall]

primatic or coil gone wouldnt affect the mains cold

The kitchen cold tap and bath cold tap upstairs are both fed from mains. The last couple of days when we run a bath for our boy, the water has a brown tint and there is tiny rusty bits settled on the bottom of the bath.

After some experimentation this is what I've found:

- The bath cold tap is the source of the brown water
- The kitchen tap runs clear when the bath tap is OFF and runs the same brown when the bath tap is ON
- Hot taps run clear

How else can the bath tap effect the kitchen tap.

Has the water supplier been working in the area.

 

[Agile]

Has any changes been made to ANY plumbing or heating?

New or replumbed washing machine for example?

Tony

 

[scubapete]

Thanks for the replies.

There's been no work done on the plumbing or heating recently. The last work was in April when the boiler was serviced. Heating has been off since late spring.

About two years ago, I replaced the entire bathroom suite and the asbestos water header tank with a plastic one. I know that the mains coming up from the kitchen is T'd in the bathroom with one branch feeding the toilet cistern and bath tap and the other branch going up to the two tanks in the loft. The sink cold is fed from the c/w cistern so it's equal pressure to the hot.

Coming into the house, I think the mains is T'd again with one branch going upstairs and the other branch feeding the kitchen tap, outside tap and washing machine.

To make it more confusing the offending bath tap was running clear this morning.

 

[doitall]

But has the water company been doing any work on the mains in the street.

 

[kevplumb]

if it was in the main john i would expect the dhw header tank to be discolored

this dont make sense

 

[doitall]

If there's contamination in the mains, perhaps it need the high flow to move it.