Welcome! Here are some tips for using this forum.
Boiler heat exchanger cleaner
I am now starting the see effects of Colorado LP (supposidly the dirtiest in the nation) on condensing boilers. My oldest condensing boiler are now 18 yrs old. Some customers do service and others don't. I have been using CitriSurf 3050 as advised by Viessmann. Today I worked on a Vitodens boiler I install 12 yrs ago which has been fully service by me 4 times. I had a very hard time cleaning the gaps of the HX in order for the condensate to drain. I left the CitriSurf in the HX and went to lunch. Before lunch it was pretty plugged along the bottom. After I, I have able to loosen and clean out about have the gaps. I drained OK. I am wondering what else I could be using as a cleaner on these older,less services boilers. I broke an old CC trying to clean the gaps. I spoke with Citrisurf and they said letting it sit in the exchanger for an hour was plenty of time for the cleaner to break down the "Smegma". Any thoughts are appreciated. Jeffrey