Open systems rust FAST! Clean up advice needed........

[deerefanatic]

Well guys. I have my 1250 gallon stainless storage tank and heat exchanger...... I used black iron pipe to plumb it all and cast iron circulators.. I had some anti corrosion chemicals from WoodBoilerSolutions that I was going to put in, but in the mix up last fall never got it in.... No probs for one season I thought... WRONG!

I pulled the system apart yesterday to replace the cast iron wye strainer with the brass one I'd bought that was back-ordered half the winter....... And that's when I found the scaly rust and brown water...... I've drained it all out, but I've got to do something now. I suppose I could just flush it out with some water to remove the loose stuff and then fill and put the anti-corrosion chemicals in to keep it from progressing further... Or I could run cleaner of some sort and get the rust out..... I talked to Cozy Heat today (they handle the WoodBoilerSolutions products) and their scale & rust remover is $110 for 5 gallons, and I'd need 65 gallons at the lightest concentrations recommended..... Waaaaayyyy too expensive. I can replace all the plumbing for way less than that (probably for the price of 5 gallons to be honest...)

Then I remembered that acid will remove rust. What do you guys think of filling the tank with water and a gallon or two of muriatic acid? Circulate for a day and then drain and flush...... Or just forget it and get clean water with anti-corrosion chemicals in it and keep moving......

 

[sdrobertson]

Well guys. I have my 1250 gallon stainless storage tank and heat exchanger...... I used black iron pipe to plumb it all and cast iron circulators.. I had some anti corrosion chemicals from WoodBoilerSolutions that I was going to put in, but in the mix up last fall never got it in.... No probs for one season I thought... WRONG!

I pulled the system apart yesterday to replace the cast iron wye strainer with the brass one I'd bought that was back-ordered half the winter....... And that's when I found the scaly rust and brown water...... I've drained it all out, but I've got to do something now. I suppose I could just flush it out with some water to remove the loose stuff and then fill and put the anti-corrosion chemicals in to keep it from progressing further... Or I could run cleaner of some sort and get the rust out..... I talked to Cozy Heat today (they handle the WoodBoilerSolutions products) and their scale & rust remover is $110 for 5 gallons, and I'd need 65 gallons at the lightest concentrations recommended..... Waaaaayyyy too expensive. I can replace all the plumbing for way less than that (probably for the price of 5 gallons to be honest...)

Then I remembered that acid will remove rust. What do you guys think of filling the tank with water and a gallon or two of muriatic acid? Circulate for a day and then drain and flush...... Or just forget it and get clean water with anti-corrosion chemicals in it and keep moving......

First I think you need to refresh us on the details of your set-up...how much pex, type of heat exchangers if any, number and what connects all of the radiators together, and I see that your storage is stainless so I'm guessing that you are not running any liner.

 

[deerefanatic]

The system is split.... The boiler and ALL heat loads are closed system........ Only the storage is open. The two are seperated by a 70 plate stainless heat exchanger. The tank has bout 25 feet of 1.5 inch black pipe and various valves and fittings and two Grundfos 15-58 cast iron pumps.... The tank is 304 stainless. (Old milk tank)

 

[jebatty]

Those who know stainless better can comment, but it seems unlikely that the stainless is compromised. FWIW, consider replacing the black iron pipe and black iron fittings, clean any brass valves, etc., flush the open system side of the HX with muriatic acid, drain the stainless tank and clean the inside with water to remove any scale and deposits that collected in the tank, add a hot water filter before the HX to minimize any future clogging or deposits, then refill with treated water from Boiler Solutions. Talk to Boiler Solutions directly. May have better ideas.

 

[deerefanatic]

You know, that was exactly the same Idea I had...... Just replace the iron/fittings and start from scratch the right way..........

Oh, and I already do have a nice fine-mesh wye strainer before the heat exchanger......