Question About Rust

Brad White_79

Ideally, Dan, cleaning your piping should be a one-time thing. Closed water systems with the O2 removed- the water is like gold. Assuming you do not drain it for service, leave it alone. And if you do drain it, recover the water and pump it back in. Best investment I made in this regard is a Silver King force pump. I heard about it here on The Wall. For about $140 it is simple and I can inject various chemicals or replace water drained when I work on improving the system.

To start, I would write to George or Dwight at Rhomarwater.com

http://www.rhomarwater.com/

What I did was to flush the system of all loose material, fill it with clean water. I filtered mine through a $30 GE Smartwater filter. Start with HydroSolv per the directions, flush again, thoroughly. Then I treated it with Rhomar 922 also per the directions. There is an O2 scavenger in that as well. Vent and fill to pressure. Fire it up to drive out any excess air, vent again and you are done.

The HydroSolv will remove a lot of old stuff so it will not come out unpredictably. The 922 coats and passivates the metals among other things.

Your draining really has restarted the corrossion cycle is all.

Brad


EDIT: I posted some Rhomar literature for you.
BEW

Dan_15

I've been remodeling my bathrooms, and the cast iron recessed radiators have been disconnected and drained for the past three months during the project. Yesterday, the plumber finally reconnected the rads, I ran the system and bled air until water came through. The water is rust colored. Should I be concerned about rust infiltrating my system? My boiler is a Buderus 215/4 hooked up to a converted gravity system.

P.S. Just discovered the plumber left one of the fittings leaking so I had to partially drain the system below the level of the leak. Should I be concerned about leaving the system drained for too long until the fitting can be fixed?

Always learning
Thanks.

Brad White_79

Rust

Free iron is not a good thing if the boiler has a stainless steel or copper heat exchanger due to deposition. Yours is cast iron so not a strong issue. Still, the presence of particulates will eventually wear any metal or material softer than the particulates. Noryl or other plastic circulator impellers would be on that list.

As a baseline for safety and longevity, I use Rhomar products to clean and passivate the metals in my heating systems, especially those with multiple metals. And I use a Neptune filter feeder (2 gallon) for continuous side-stream filtration . I use this as a full-flow device before start-up. Maybe above and beyond but that is what I do.

Dan_15

Thanks for the advice. Ive got a MegaStor indirect hooked up to the cast iron Buderus for DHW which has a stainless steel HX if I am correct about that. The circs are all grundfos--not sure if they have plastic impellers. Bottom line, I guess I should be cleaning the system at least annually, and probably once after all the remodeling work is done. I'll look up Rhomar. My system has mixed iron and copper fin tube. The big mains are 85+ years old, and Im not sure if they have ever been "cleaned" other than drained once in a while. Is there a preferred method or product for cleaning and then treating on an ongoin basis?

Thanks.

Jerry_15

I love my silver king force pump, and use it mostly to put in silver king stuff, but it also works great for glycol, hydro-static pressure tests (100 psi max)bailing out toilets etc. #5 solution works well in my experience for this application, and filters are a wonderful thing, but I'm not so sure about doing yearly flushing. unless there is an obvious problem. I usually just check the water condition, and blow out the strainer. That oxy dead water can go on forever and I think constant/regular replenishment might be counter-productive.

Dan_15

Thanks for all the advice. You're right, why would I ever want to drain the water annually and introduce more O2. I'll do what I can to flush it once the remodeling is done and then leave it be.

Dan

Drew_2

Deposition

Brad, you wrote:
Free iron is not a good thing if the boiler has a stainless steel or copper heat exchanger due to deposition.

What is deposition? I've never seen that term.

Drew

George_10

Dan

You can call me at 800-543-5975 and we could discuss what needs to be done to clean and treat your system.

A cleaned, non-leaking closed loop system only needs to be cleaned once. The treatment followup of the cleaning will prevent further scale and corrosion. This also will keep the efficiency closer to design levels and therefore save on the fuel bills.

Look forward to speaking with you.

George

@RhomarWater.com

Brad White_9

Deposition

is the layering of one material on another such that the material in flux bonds to the base metal by any number of means. Corrosion or fusion, much as any fouling attaches to any other material. Maybe I did not use the term correctly as a chemist might (I am not one) but that is the term I always used when discussing fouling.

This process is of course different from "deposition" wherby lawyers become cats and you, a ball of yarn.



I would be happy to be corrected or get a clarification from you, Drew.

Brad

Dan_15

I talked with George and he walked me through the process to clean and treat. My problem now is that I do not appear to have any sort of inlet on my system for introducing the Hydrosolv. I do have a boiler drain and a drain on the boiler inlet pipe to my indirect tank. If I got a pump like you suggest, could I pump into the system backward through a drain or do I need to have an inlet installed?

Brad White_9

You have what you need, I believe.

You have a drain valve, into which you can inject the HydroSolv. Let it circulate and drain out the same path. I would isolate your domestic water fill during the operation just the same, even if you have a backflow preventer.

But if you have two valves, that is OK also, so long as each circuit will see the volume of the system eventually. One valve will work. If you have two and can isolate the path between them, you can hook up a hose with vacuum breaker to fill into one and flush drain out the other. Takes much less time than a tidal ebb and flow into one valve.

Are you going to get a Silver King pump?

Drew_2

deposition

Brad
No clarification needed past the one given. Just not a term I was familiar with.
Thanks
Drew

Dan_15

That makes sense, thanks. I'm not sure about the expense of the Silver King pump. Think I could use it to purge my sprinkler system every year? That could justify it for me (save me $75 a year on sprinkler maintenance). Not sure where to get the pump.

Brad White_9

I got mine at my local supply house

but they are available on line. About the same money. Silver King Force Pump


Hey, I just did a web search and the price went down... dammit


http://www.accentshopping.com/product.asp?P_ID=150506&strReturnUrl=

Mike T., Swampeast MO

Beyond Deposition

I've been told that it's possible for rust to replace elements in stainless steel that make it "stainless".

A molybdenum based inhibitor supposedly prevents this from happening. A "side-arm" filter capable of filtering suspended rust particles is also recommended in addition to a "shock" treatment of 2-3 times the normal dose of such molybdenum-based treatment. The side-arm filter will supposedly clog VERY rapidly during the initial treatment but since it only receives about 10% of the flow, it won't affect total flow if you don't clean the washable filter.

As with anything related to water I suspect this potential problem is highly related to the base chemistry of your fill water. The one true consistency I find regarding water chemistry in hydronic systems is that naturally soft and acid water spells bad news.