Viessmann Replacement

Paul Pollets

In 23 years, I've only replaced 2 Viessmann boilers with a newer model, and this project was the 2nd. The original installation(s) were done poorly, with little regard for circuit sizing, near-boiler piping or correct pump sizing. The AR boiler was power vented and used propane. The control was the Trimatic-MC with clock timer cube, the 2nd generation ODR from Viessmann. The room was 4ft x 4 ft which hampered the replacement, especially when re-using the original 53gal VertiCell indirect. We managed to install a new Vitodens 200 B2HA-35 with 3 temperature circuits. Running extremely long 5/16 pex (over 350 ft) is NOT recommended. I'll post pictures of the new system next week.