Preheater Exterior cleaning

[DocsMapleSyrup]

Last year was my first year with a preheater. At the end of the year, I ran 65 gallons of fresh water through the preheater to clean it out. I also decided to try letting the left over partially boiled sap set in the pans for cleaning. After about two months, I cleaned the pans. It stunk like vinegar but worked. What I noticed however, is that with the moist environment the preheater was in under the hood, the outer copper tubing developed quite a bit of oxidation with green color to the exterior of the preheater pipe. What should I do to clean this prior to boiling sap this coming spring?

[Bucket Head]

I'm not sure what cleaners or solvents might clean that up. On the other hand, you probably don't want those anywhere near the evaporator anyway. You might be looking at a lot of wire brushing (power or by hand) and sandpaper or Scotchbrite action. Along with copious amounts of elbow grease. That would be the safest way in my opinion.

[OGDENS SUGAR BUSH]

if its copper wash it down with tomato juice and rinse with water. Copper will look brand new

[Sinzibuckwud]

And a little ketchup and 00steel wool for those tough spots.

[tcross]

not sure the size of the preheater you have, but if you can soak it in vinegar. that'll clean it up.

[DocsMapleSyrup]

I've got a 2x6 flue pan with preheater and hood. Do you think it would work to dump 8-10 gallons of vinegar and fill the evaporator and run it?

[Bucket Head]

I don't know if that would do anything for it or not. I'm thinking not. I'm also thinking hot and/or boiling vinegar isn't something I'd care to be around.

I know the time and effort from actually scrubbing it doesn't sound like fun, and it won't be, but it will get the job done and there won't be any risk associated with it. Good luck and let us know how whichever process you use works out.