Party Walls

Posts by Cathal Gleeson

Comprehensive Heating Upgrades for Two-Pipe Steam Systems

Most people who have lived or worked in a steam-heated building are familiar with the typical occurrences of uneven heat (underheating/overheating), banging pipes, and having to open windows all winter long.  Not only are occupants uncomfortable, but the heating bills are high as well. Balancing these systems is a huge opportunity for energy savings. It is important to point out that the root of the issue is in the distribution system, and it’s that distribution system that needs to be fixed. The steam traps are the weakest –link and when they fail, residents lose the ability to control the amount of heat delivered. This in turn makes the space uncomfortable and results in the necessity to open windows and waste fuel. The steam traps are supposed to be replaced building-wide every three years to catch broken traps, but due to the expense and logistics of such a task, this is rarely actually done.


Linkageless Burner Retrofits for Steam Boilers

Going Beyond Carburetor Technology in the NYS Market

Fun Fact #1: Space heating and domestic hot water generation represent two of the greatest energy end uses in New York State.

Fun Fact #2: More than 70 percent of all New York City buildings utilize steam for space heating.


The clear majority of the distribution systems in these NYC buildings are supplied by high mass steam boiler plants. Digging down a bit further, it is important to note that the most common air:fuel control for these boilers is a mechanical linkage that connects a single servo motor to both the combustion air damper and the fuel control valve(s). We know that adjusting one part of the linkage’s movement affects fuel and air rates elsewhere in the range, making accurate adjustment difficult. We also know that modern linkageless controls use separate servo motors to operate the fuel control valves, combustion air damper, and (in some cases) the flue damper, allowing for finer control.

mechanical linkage system and linkageless system

In fact, SWA recently completed a demonstration study (partially funded through NYSERDA’s Advanced Building Program) to evaluate linkageless burner retrofits on two buildings with respect to energy savings and carbon reductions, as well as qualitative or non-energy benefits. The retrofit materials were funded by Preferred Utilities Manufacturing Corp. of Danbury, CT, who also provided manufacturer’s technical support. The study also focused on quantifying the seasonal efficiency of intermediate-sized, high mass steam boiler plants, which had not previously been studied. The demonstration addresses this gap in the industry’s knowledge.