I have a hot water sediment problem. A new water heater (American brand) was installed in 2002. Gradually thereafter, an aqua, somewhat gritty gel began accumulating on the washing machine water valve inlet screen (hot water only), and screen would quickly clog. This became such a problem, I removed the screen from the valve, but this shortens the valve life. Particles would also collect on faucet aerators, but to a lesser degree. Long story short, I eventually contacted the water heater manufacturer - their diagnosis was an anode rod interaction (rod was aluminum). In 2006, a new water heater (same brand/model) was installed, but with a tin/zinc anode rod. Problem seemed to be better, for a while. I just recently had to replace the washer water valve again, and left the screen in. But in only 2 loads of wash, the screen completely clogged with the same aqua gritty gel.

House is nearly 100% copper pipe; just a couple of vertical runs of the original galvanized plumbing still present. Old water heater was a Rheem, and didn't seem to have this problem (I have no idea material the anode rod was, etc.). Pipe connections at the water heater are all via dialectric(?) couplings, though I don't recall these being present with the prior Rheem model.

I'm very frustrated with this problem. How can it be solved?

an aqua, somewhat gritty gel began accumulating on the washing machine water valve inlet screen (hot water only
What do you mean by "aqua"? Please explain. Is the substance metal, plastic or what? What color is it? Have you pulled and inspected the anode rod? Was it ate up? Well or city water? Don't make us guess, furnish us with details to work with.
Regards, Tom

What do you mean by "aqua"? Please explain. Is the substance metal, plastic or what? What color is it? Have you pulled and inspected the anode rod? Was it ate up? Well or city water? Don't make us guess, furnish us with details to work with.
Regards, Tom

Tom,
Aqua implies bluish-green in color. I do not know what the substance is, though am almost certain it isn't plastic. It strikes me more as metal-based. I have a sample of the sediment being analyzed by a lab specializing in metallurgy. I have not attempted to pull the anode rod - my prior experience with trying to remove rods is they are installed so tightly, I could not budge it. This is city water.
Regards, Alan

At first I thought it might be some solder flux. After it sets in copper for a time it will turn a greenish blue but that doesn't seem to be the case here, Do you have a wafer softener installed? Pump or city water? No problem before the new heater was installed? Any more details that you can furnish?

. I have a sample of the sediment being analyzed by a lab specializing in metallurgy Please let me know what they find. Regards, Tom

Where are the connections between Galvanized and Copper? Is there a dielectric union between them so that there is no direct contact? Over time there will be corrosion that can cause problems. It could come out green simply from the copper corrosion. Just throwing out a couple ideas.

@Speedball1 good call on the softener, if it was just barely installed it could have that effect if wasn't rinsed out properly, but once all the factory gunk got cleared out it wouldn't have such a reaction unless there are metals in the water?

At first I thought it might be some solder flux. After it sets in copper for a time it will turn a greenish blue but that doesn't seem to be the case here, Do you have a wafer softener installed? Pump or city water? No problem before the new heater was installed? Any more details that you can furnish?
Please let me know what they find. Regards, Tom

Tom,
No water softener. And solder flux makes no sense to me - there was very little pipe work done when the first (and second) water heaters were installed - certainly not enough to create 6 years worth of this problem. Per my other reply, this is city water (which I would actually rate as very good water). And yes, there did not seem to be any problem prior to the new heater install in 2002, and the second one in 2006 with the different anode rod certainly hasn't eliminated the problem. It will probably be at least next week before lab results on the sediment sample.

Where are the connections between Galvanized and Copper? is there a dielectric union between them so that there is no direct contact? Over time there will be corrosion that can cause problems. It could come out green simply from the copper corrosion. Just throwing out a couple ideas.

@Speedball1 good call on the softener, if it was just barely installed it could have that effect if wasn't rinsed out properly, but once all the factory gunk got cleared out it wouldn't have such a reaction unless there are metals in the water?

No water softener. All of the galvanized/copper connections are 90 deg elbows, and appear to be copper - internal threads on the end threaded on the galvanized pipe, and soldered to the copper pipe on the other end. There are only 2 of these on the hot side in the entire house. I've lived in this house since 1999 and never touched them, so would be very hard pressed to think these are the problem, when no problem existed prior to the first new water heater in 2002.

I suspect old galv piping. Replace all galv. Best first step to take.