Fernox 57882 F3 System Cleaner 1 Pint

When I first bought my home the pipes knocked like crazy. I was worried that it would damage something (pipes or solder maybe the framing of the house etc) so I did my thorough research and boldly bled the boiler. I didn't realize there's anti corrosion chemicals mixed into the liquid in the pipes. About 2 years later, my whole boiler was starting to rust. From what I could see at least. It seemed drastic and sudden, every pipe going to and from the boiler was suddenly rusted. I did more research and found out, I needed to clean the system with this, then drain it and refill it with the f1. (Why is it backwards that's so confusing. Is it because you fill f1 first and then f3 is if you're a homeowner who bled the boiler). I learned more about the boiler than any other appliance in the house. I understand the boiler after all this. I turned it off and let it cool until the big cast iron pipe at the bottom of the boiler was touchable. Supposedly that's the temperature the boiler would be? I don't know, I turned turned off all the zones but the first one. Luckily I found the manual for my boiler and was able to follow their filling instructions. That made it much easier since they mentioned my boiler automatically limits filling to 12 psi. I bought a small hand pump, I attached hoses to it with hose clamps and screwed it onto the first zone. Before bleeding I opened the zones outlet with the siphon going into the bottle, I just quickly forced it in, closed it and moved on to the next zone. After all the zones were done. I went back to the first to just open it for half a second to break any bubble or seal . It seems to really clean the system. After draining and filling the f1 it made the pipes look pretty much like the day we moved in. I'm surprised how much it affected the rust damage. Very cool stuff!

I suppose it works. I drained the boiler until as clear as possible then I poured this in and left it for a week with the boiler heat on. After which I drained again until clear. Filled the boiler to spec and added the F3… works… water in the level shows the gunk settles leaving the to crystal clear

This cleaner was recommended to me for the high efficiency boilers we have. It was easy to use and appeared to do a good job on boiler and boiler/water water heater.

Used for a high efficiency water boiler and indirect heater. Seems to clean well and so far no problems for two years.

Seems to work.