Little bit of orange water out of water heater

[rural_engineer]

I have a brand new AO Smith Voltex HPTU-66N heat pump water heater. I have brass elbows on the inlet and outlet connecting to 24" stainless corrugated flex hoses (forming a heat trap), connecting to various brass fittings and a mixing valve. Whenever I run hot water, the very first bit of hot water that comes out is orange-brown. It's maybe a quart. Afterwards, the water is not orange, but it has a lot of dissolved gas.

What would you suspect is wrong? Do you think the dip tube is bad? Do I need a different anode? Where should I start debugging?

I'm on slightly hard city water that comes from surface water and wells that is treated to prevent corrosion in the city pipes.

Thanks!

 

[Fitter30]

There is something that is made of iron or plain steel that is rusting. If you take a 1/2" black pipe cap in a system it will do the same. Years ago replaced a prv and month or two later it started the orange water. Replaced it with another brand problem went away.

 

[Sponsor]

 

[rural_engineer]

The only carbon steel in the system, as far as I can tell, is the galvanized nipple on the j tube at the outlet. The elbow on the tank is brass. The flex hoses are corrugated stainless. The mixing valve and surrounding fittings are brass.

I figure the issue has to be between the tank outlet and the mixing valve, because I only see color just as the water warms up, and then it goes away. I figure I should just go, drain the tank a bit, pull apart the outlet connections, and look for corrosion.

 

[rural_engineer]

The outlet nipple is rusting.

 

[rural_engineer]

What I have, the brass street elbow and stainless flex, is clearly not ok. What should I replace it with?

 

[rural_engineer]

The inlet, which has the exact same setup, has no corrosion.

 

[John Gayewski]

Try a stainless 90. Not sure it'll help but it's a cheap thing to try. Stainless is cheaper than brass. Otherwise it's just your water heater construction. Not much to do about it. There is an outside chance it could go away when the metal has had a chance to form a mineral protective layer.

 

[rural_engineer]

I found some different brand brass fittings in my junk box, and gave them a try. I wrapped the heck out of the new elbow with teflon tape. If that doesn't work, I'll try a stainless elbow next.

 

[Fitter30]

Do u have a pressure valve? Might want to pull it just to inspect the piping in and out or just the tank in connection. My case even though the prv was for potable something inside it wasn't. Wonder if the glass lining of heater is cracked or chipped and tank is rusting. If cold inlet is clean has to be the tank. Red vrown on oulet is iron oxcide.

 

[WorthFlorida]

I tried a search on this forum and this problem I believe was asked not long ago. Heat pump tanks do not have heat trap nipples, therefore, the interior of a galvanized nipple is not fully coated. I'm sure the other post he used a brass nipple and it fixed the problem.

 

[rural_engineer]

Well, the new brass fittings didn't fix the issue. I think I'm going to reach out to the water heater vendor, and see if I can get a replacement dip tube, and then hook up to it with a fitting that uses a gasket and covers the exposed metal.

 

[rural_engineer]

Are there 3/4" FIP swivel elbows in brass or stainless? I want the gasketed fitting you normally see on flex water heater hoses, but on an elbow instead of a hose.

 

[rural_engineer]

Could I used this fitting at the outlet of my water heater?

 

[rural_engineer]

I just got off the phone with AO Smith and the vendor, and I've got a warranty replacement for the dip tube on backorder.

 

[John Gayewski]

Could I used this fitting at the outlet of my water heater?

I don't think so. But you should be able to find a 3/4" npt swivel adapter. I will warn I don't think they are necessarily for water. Generally more for air or things that don't matter as much if they leak a little.

 

[rural_engineer]

I ran by the local supply house and got a 3/4" NPS x 1/2" NPT meter coupling, and a 3/4" to 1/2" bushing. The meter coupling fit perfectly, so I suspect the A Y McDonald fitting would do the job.

I'll give this setup a day to see if the gasketed meter coupling fixes the yellow water. If it does, I'll see about ordering a 3/4" NPS x 3/4" NPT meter coupling to install when the warranty dip tube arrives.

 

[rural_engineer]

This is my temporary fix until I get a warranty dip tube and a 3/4" NPS x 3/4" NPT fitting. It has eliminated the yellow water.

 

[Reach4]

Interesting. It is hard to imagine how that temporary fix changed things much regarding yellow water. I am thinking you have a plastic-lined steel nipple (dielectric nipple) coming out of the WH. So my idea is that the new fitting ran brass much closer to the plastic, keeping the steel more separated from the water. Does that new fitting have a gasket that contacts the nipple? I see you are not using PTFE tape on the new installation, and you don't use tape with a gasketed connection.

If this is the cure, then I don't see how a new dip tube will change things. I expect the dip tube is plastic, or at least not steel.

 

[rural_engineer]

If this is the cure, then I don't see how a new dip tube will change things. I expect the dip tube is plastic, or at least not steel.

I think this photo of the replacement dip tube assembly will make it clear why a gasketed fitting helped.