Viessmann Vitodens 100-W Boiler Overview

New home construction, installed 4 years ago, nothing but problems ever since. Even with original installer and support from Heat Tech (Vieseman's authorized tech support team in Connecticut.) no one can make this system work properly. It overheats, it underheats, and then sometimes it downright breaks and requires expensive replacement parts. All the boilers have broken completely in the past two months. Very expensive repair bills and heating bills, when it overheats the house. We have radiant heat and forced air so part of the problem may be calibration between the two systems, but after four years you would think it would be dialed in by now, total frustration and Viessmann boilers are at the core of the problem.

I heat a well insulated radiant heat floor but is a complete disappointment when it comes to hot water. It was installed this last fall and has never worked properly. When someone takes a shower or uses one of the faucets, it will stop supplying hot water suddenly. Obviously makes for a very bad experience in the shower. The heater has more than enough capacity for this small apartment. I am not happy at all. My installer has not been able to fix it.

Installed a Veissman hot water boiler system in Oct'18 to replace our original boiler over 50+ years old. The contractor did a great job with the install but it sounds like a jet plane when it starts up! Is this normal? Our old system never sounded like this.

We moved from an oil furnace to a propane furnace. The Viessman 100 was our choice due to the fact we were also installing a propane fueled generator (Generac) This unit is great. It keeps our home warm and also provides hot water. So no need for an electric hot water tank! Highly recommended, quiet, small and efficient!

Costly to maintain shit product! Within 2 years of usage the repair and maintenance cost is equivalent to buying a 2 brand new ones. Viessman crap!