Issues with radiant heat boiler-maybe go with a Takagi?

The tankless water heater discussion reminded me of the Takagi type boiler alternative for the radiant heat system. My Teledyne Larrs unit keeps clogging at the heat exchangers every year. (This unit was installed about 1998 to replace the unit installed in 1994 that failed. Though out of warrenty, Teledyne and my great installer took care of it) Last year it was dissasembled from the top to deep clean the heat excahngers. A week or 2 ago the boiler fired up due to the cooler nights we had and in the morning, I noticed the on-board shut off switch was tripped because the boiler was overheating. That tells me it's clogged again.

I'm contemplating two options, either learn to clean the heat exchanger fins and gas injector manifolds myself and figure out how to keep it from clogging, or go with a Takagi tankless unit. My radiant heat service guy has installed many and they sound like a great alternative. Pretty much maintenance free.

The reason I understand the heat exchanger fins are clogging is due to the cooler water entering a hot boiler. The cooler water cools the heat exchanger fins that then cool the air inside and then creates condensation inside the boiler that rains down and the minerals in the moisture build up on the cooper fins and clog them. My boiler installer had a by-pass pipe added that pre heats the in-coming water into the boiler to reduce this problem. It's not working too well or there's another issue at work here.

Any insights is appreciated!

Nelson