Black Water

tocker

I reposted this. The water in the manifold gauges is very black. This is the second year of operation. Toward the end of last heating season the water looked a little rusty brown and so I flushed with Fernox and flushed again and refilled with fresh water. While the flush didn't take all of the rusty crud out of the gauges on the manifolds, it looked better. Now the water is black. Pics below.

My boiler is a Lochinvar WHB110 and Caleffi Hydro Sep with 3 Taco ECM variable speed circulators (VR1816), out to 3 zone Caleffi manifolds, then Uponor HePEX to new panel rads. System is quiet, so air doesn't seem to be an issue. Water is running at 150 degrees max during this cold snap to 10 degrees. Usually water temps are less than 130. Install happened during a basement renovation and was up and running last Winter before the walls were closed in. I didn't see any leaks then.

If anyone can point me in the right direction, I would appreciate it.

mattmia2

You could add a dirtmag. The fill water will have some oxygen in it and will produce some rust and it will settle in low spots. Oxygen barrier tubing also lets a little oxygen in. That seems normal.

hot_rod

We call that "boiler ink" its the natural color the fluid will get if there are ferrous components in the system. It is almost impossible to keep water crystal clear in multi metal hydronic systems.

Is that a Sep 4 with the magnet? If so blow it down into a plastic jug after a year. if you get a lot, handful, of fine magnetic particles, then you haver an O2 ingress problem,. Some dirt and color will be normal.

Do you have a Fernox test kit? That will indicate any upcoming issues.

I use Rhomar brand and it has a film provider which puts down a very thin protective coating on all the insides. It turns a dark grey color also.

tocker

Bummer, I hope that this doesn't cause problems down the road. I used Fernox F3 to flush it, but nothing else.

I didn't get the test kit. I'll buy it and the Rhomar. Should I do this now/mid-season or wait?

Yes, it's a Sep4 with the magnet.

I think it is odd that the Lochinvar has a system pump with a cast body/volute. Also, I used the Taco VR1816 ECM pumps with the same. Also, the tee for the vent is cast.

Should I change those out?

tocker

Thanks Gents! Merry Christmas!

hot_rod

tocker said:

Bummer, I hope that this doesn't cause problems down the road. I used Fernox F3 to flush it, but nothing else.

I didn't get the test kit. I'll buy it and the Rhomar. Should I do this now/mid-season or wait?

Yes, it's a Sep4 with the magnet.

I think it is odd that the Lochinvar has a system pump with a cast body/volute. Also, I used the Taco VR1816 ECM pumps with the same. Also, the tee for the vent is cast.

Should I change those out?

Are those Delta T function circs? If you are not using that function, don't know why you would. No need in buying a circ at that cost for s function you do not need or use.

My Knight came with a Grundfos 25-104 variable speed circ that is controlled by the boiler.

Stainless steel circs are quite a bit more $$. I doubt boiler manufacturers will ship those with boilers, knowing that steel and iron are typically in all hydronic system, what would be the point?

If you are sure the system mis 100% leak free, no reason not to add a conditioner now.

Mad Dog_2

Nice, neat , sqaured away job! Mad Dog

tocker

Thanks Mad Dog. While it isn't my profession, I loved doing it and learning about hydronics, HVAC etc. My first....took me months of trial and error in design. I loved it but owe a big thanks to the oversight by a very good/patient, commercial HVAC contractor friend who helped me through video chats and a couple of visits during the pandemic. I learned a lot...would love to put what I learned to use somewhere. Unfortunately, there aren't many contractors in this area who install boilers any more.

tocker

hot_rod said:

We call that "boiler ink" its the natural color the fluid will get if there are ferrous components in the system. It is almost impossible to keep water crystal clear in multi metal hydronic systems.

Is that a Sep 4 with the magnet? If so blow it down into a plastic jug after a year. if you get a lot, handful, of fine magnetic particles, then you haver an O2 ingress problem,. Some dirt and color will be normal.

Do you have a Fernox test kit? That will indicate any upcoming issues.

I use Rhomar brand and it has a film provider which puts down a very thin protective coating on all the insides. It turns a dark grey color also.

Hi Hot Rod, I'm revisiting this. Found a small leak in one of the rad plugs, which I fixed. Couldn't find the Rhomar products in stock around here. I'm looking online again. Which of the products do you recommend for the system shown here with Uponor PEX, steel rads, preferably to clean and to scavenge oxygen?

hot_rod

Fernox, Adey, sentinel, Oadey/ Rectorseal , are other brands

tocker

Which Rohmar product do you use?