When Traps Go Bad

What caught our eye. Steam traps. 

Say what? The little buggers on half the radiators in town, and one of the big reasons some apartments have too much heat while others are cold. But to really understand why your building’s heat may be unbalanced, you have to know a bit of history.

Back in the day, New York’s apartment buildings used coal to fire boilers. These boilers often ran non-stop, and it was normal practice for residents to keep their windows partially open. They needed cool air to counteract the 24/7 heat cycle, and there were health concerns that people believed having “fresh air” could counteract. When heating systems were converted to oil, modernization didn’t follow. Some needed technologies were not available, fuel costs were low, and people didn’t change their practices. Today’s radiators are trying to function in an energy-efficient world, but it’s tough. They were originally sized for single-pane windows – which were frequently left open, no less. 

Flash forward to now. Coal gave way to oil, which is giving way to natural gas. The fuel is different, but the steam system isn’t. In most large apartment buildings it’s a two-pipe system, which means as steam goes up one pipe it pushes the air out, and then water (and air) drain down the second pipe, called a return, ending up in the basement. 

So? Problems occur in the hand-off between pipes, which is the steam traps. They’re supposed to keep steam out of the return lines, but they start failing after about three years. A failed trap is one that is stuck in an open or closed position. You won’t find out about the ones stuck open because the radiator still gets hot, but rest assured, your system is being harmed. If air is trapped in your system, everything becomes unbalanced. “Once a handful of traps go bad,” says Jonathan Flothrow, Senior Building Systems Consultant, Steven Winter Associates, “the entire system is screwed.” 

To reset. So what’s a building to do? Consider the orifice plate. Fit your radiator with it and you will have hit the steam system lotto. Orifice plates are small, bottle-cap sized plates with a small hole in the middle. If properly sized for your system, they make radiator traps unnecessary and will help even out the heat. Plus – and this is a big deal – they never fail.

“Think of it like this,” says Flothow. “If you lived in the suburbs you might water your lawn using a soaking hose, which is long and flat with lots of tiny holes running the length of it. The same amount of water comes out each hole, and the reason is because you have low resistance through the run of the length of the hose, but high resistance at each hole. The combination of low and high resistance points is how systems that distribute fluids are balanced.”

Take advantage of the reset. Local Law 87 is the law that requires your building to submit the results of an energy and systems audit to the city every ten years. And to do that audit, your expert will have to check the state of your steam traps and, as required in the law, replace them to maintain efficient operation of your heating system. For forward-thinking boards, this presents an orifice-plate opportunity. 

The bottom line. Sometimes the most vexing problems can be solved using the smallest, least expensive solutions. That said, though, changing steam traps or installing orifice plates requires someone to go into every apartment and work on every radiator. Seizing upon the requirements of Local Law 87 might provide your board a solid reason to tackle such a project. 

To take a deeper dive into the issue, read Clanging Pipes and Open Windows - Upgrading NYC Steam Systems.