Posts Tagged ‘Viessmann’

Boilers Part 15 – Turndown

November 25, 2010

Hi Again, Turndown is the ability of a boiler to reduce its input to match the load. Imagine a home with 3 floors and a separate thermostat and heating zone for each floor. When all three floors require heat, the demand might be 80,000 BTUH. This would require an 80,000 BTUH boiler. If only the basement needed heat, the load might only be 20,000 BTUH. Firing an 80,000 BTUH boiler would be overkill and horribly inefficient. All DVCB have a turndown that allows the boiler to fire at the required rate for that time so the boiler would fire just at the 20,000BTUH that you need. Efficiency is enhanced once again.

Now that it is crystal clear that the best option for a boiler is the DVCB, Direct Vent Condensing Boiler, I would like to discuss the problems with these boilers and how to avoid them.