Buderus GB162-25 heat exchanger clean up

Dan22

Hello, own gas boiler Buderus Logamax plus GB162-25 for almost 10 years. Every year I called for service, a guy came, cleaned something, took the money, and left. I asked about the heat exchanger, he said that everything was fine, he cleaned everything. In recent years, the efficiency of the boiler has decreased noticeably. I thought about the bad caloric content of gas, until one person recommended checking the condition of the heat exchanger yourself. The view was shocking. I tried washing it with water, but there was no result. Soot is hard as stone. How to clean it? Is there some kind of chemistry? I don't think trying to burn it will lead to anything.

Mad Dog_2

Haven't cleaned that model, but it looks very much like the Buderus GG-142 Wall Hung Gas Mod Cons.  Mineral oil, a few different size brushes..get it hot first...  Look online for Procedure or call Buderus/ Bosch Tech Support.  Ask for Chuck Shaw.  He really knows the products inside & out and is one of the Smartest Plumbing & Heating guys in America 🇺🇸.   Mad Dog 🐕 

tim smith

Agree with Mad dog, going to need to be soaked with mineral oil and water mix per iom manual. Then ran through burn off mode. Then flush and repeat. Call Bosch Buderus tech and see what they say first. We have had to clean pretty dirty ones in past, maybe not quite that bad but close.
Need to follow the service procedure per manual.

Mad Dog_2

Did you call The "Old Yankee" Chuck Shaw?  That was his company name.  Chuck is as smart as they come in this trade AND he works for Buderus/Bosch now. FYI...Chuck was at The Wall.from the earliest days...O miss him!  Mad 🐕 Dog 

Dan22

Buderus tech support says, need to soak in special cleaning chemicals and clean with high pressure water. Burning will not help. Let's see.

Big Ed_4

Butcher block oil is used to clean the heat exchanger ... I believe it is different then mineral oil .. Soak to let it sit and burn it out . Yours seems worst then I have seen . Do it several times ...