First, please do read Erin's post about the MIT Climate Mitigation contest Campus Zero Carbon proposal and go vote for it -- this is a big opportunity for our industry! (short link: http://bit.ly/29i7M5Y)
Second, we just gained a client with a 10 yr old 8Ton GHP that someone 2 months ago put in some CLR to attempt to "clean" the exchangers (dual coils). Now, it appears one of them is leaking refrigerant, but it might have been already leaking before the CLR was added.
We presume we must pH correct the system, but what else does anyone know about CLR ... as in must it be cleaned another way? Supposedly, some "flushing" has already occurred. And, please suggest the easiest method for pH balancing a non-pressurized system with a pretty small "tank".
Rich, regarding the CLR issue; I get the impression this is a closed loop system on an atmospheric flow center? The attached article may provide some insights. If the rubber connection hoses were crunchy when flexed its likely that the crunchy substance was iron deposition from the flow center pump bodies. This stuff has an affinity for depositing on the interior of the rubber hoses and if they are flexed will give a a crunchy feel as though the hose were hardened and not flexible. We care for a commercial system that had water and methanol as the original antifreeze where this occurred and lead to multiple system problems. If this was your new customers case, I doubt if the CLR was doing much good but if the hoses were flexed its highly likely that the iron deposits that were dislodged from the hoses came back around to clog a heat exchanger or the first pump off the flow center. If this action occurred during the winter it's possible the heat exchanger had multiple freeze-ups and the CLR was added as a means to improve flow.
At this point I suspect it needs a new flow center and if a test by stethoscope shows there is refrigerant escaping inside a heat exchanger its likely best to replace both and not take any chances. That is provided that the system suction pressure has always been higher than the pressure in the loop and any loss of refrigerant is a one way issue. If loop solution has gotten into the system as shown by an acid moisture test I suggest replacing the complete system rather than buying into a continuing problem.
The loop will need to be flushed to clean up any residual solution and any debris left in the system and corrosion inhibitors added to protect the future flow center pumps particularly if you are not using deionized water and an inhibited antifreeze. As for inhibitors its best to check with boiler / tower folks in your area to see what is available as a non-toxic inhibitor package and if the local water quality is applicable with the inhibitor. I'll often use a patch of 0000 steel wool along with a sample of copper pipe in a sample of the source water to see if there is a corrosion issue. The same test with an inhibited sample will prove if the inhibitor is effective or needs to be supplemented. It takes more time but is worth the effort when we encounter a problem system.
The attached pdf should provide more insights to my discussion and suspicions.
Jeff Persons CGD
Geo Source One Inc.
Columbus, Ohio Geothermal Heating & Cooling | Geo Source One Inc.