Should the water in my closed loop system be treated to prohibit any future corrosion problem inside the unit? If so what type of corrosion inhibitor and at what ratio. I live in the south so not concerned about freezing. I'm concerned about rusting internally. Thanks
I was thinking maybe it needed protection since you can never fully remove all air from a system. But thanks for the replies and I'll leave it be. Thanks
My thought I deal a lot with commercial. When you order a typical geo heat pump, I think the two options on heat exchange coils are copper or cupra nickel. Cupra nickel resists corrosion better. You can lose a copper coil in beach or ocean areas in two years. I agree with the previous two comments IF the water put into the system is NEUTRAL PH. Where I live, the water is so pure it errs on the acidic side. What does that mean? It means that standard copper pipes will perforate in 20 years time. One professional geo installer whom I trust locally would probably "truck in" a more neutral water in my case. Or you take a sample and have a professional chemical company ( the ones that do commercial water treatment: large tonnage water towers and so on) give an opinion on a sample you give them. There are legitimate additives that can be added to make water that is on either extreme of PH, neutral. Water that is neutral pretty much stays neutral unless there is some other outside acting influence. Hopefully your professional is using a multi thousand dollar flushing machine which would remove 99.5% of any air. Water is popular and safe, and cheap but make sure it actually is neutral. In moderate climates, it is preferred because of superior heat transfer and flow characteristics. That's my take.
Do you mean domestic potable water, or "dead water" in a closed loop? I'd expect water in a closed loop to rapidly become "inert" after depleting whatever corrosive potential it might have had initially. That's certainly my experience with a 60-year-old all-copper hot water/baseboard system that we had before the geo retrofit. Our domestic well was/is slightly acidic -- enough so that I got tired of repairing/replacing pinholed copper pipes, and gradually converted the domestic water plumbing to 100% CPVC. OTOH, the hydronic copper piping and fin-tube copper radiators were corrosion-free and like new when we removed them after 60 years of service -- even though they'd been on a slightly leaky system (boiler blow-downs, circ pump seepage, etc.) with an auto-fill valve refilling them from the slightly acidic domestic water supply. Executive summary: Leave it be. Looby
reply ================= I have had to replace all my original domestic water copper piping at my house because of pinhole leaking. I have now have pvc/cpvc. The downside? cpvc becomes brittle. You can't actually snap cut it. It just fractures. I work for an institution with many buildings having 27 years + copper domestic piping. Until they decide to replace the whole darn thing, we use pressure clamps. In fact we use hundreds of them. So much for lifetime copper! I daily deal with commercial water treatment. I still say if water is neutral, fine, if it is not neutral.....? One of the functions of water treatment in commercial is to add oxygen inhibitors, essentially chemicals that absorb free oxygen. Done correctly, pipes 60 years old will look fine on the inside, why because there is no reaction or corrosion taking place. All I'm saying is that before I circulate a lot of water through loops with copper, I would test the water I intend to add to my house. Some of the chemical guys that analyze our stuff have chemistry degrees. I listen to them. hvac
Funny thing 'bout that, so do I. Maybe a good idea, maybe not. Corrosion chemistry is a very specialized field. After 9 years of undergraduate & graduate chemistry, I know enough to know that I'm no corrosion chemist. Not even close. RE: brittle CPVC -- warm it up with a hair dryer or heat gun. Works great. ...now an escaped chemist, Looby "Anyone dumb enough to take chemistry can't possibly be smart enough to pass." -- First Law of Undergraduate Survival
