Steam System's Secret Behind the Looking Glass

by Patrick Linhardt THE PHONE CALL: A commercial controls contractor called me at the supply house. The caretaker of an estate where he did the A/C work wanted him to fix the steam system. Some rooms hadnt heated well for years. There was steam pressure at the boiler, but he just couldnt seem to get this one section as warm as the rest of the house. If he ran the boiler long enough by raising the

by Patrick Linhardt

THE PHONE CALL: A commercial controls contractor called me at the supply house. The caretaker of an estate where he did the A/C work wanted him to fix the steam system. Some rooms hadn’t heated well for years. There was steam pressure at the boiler, but he just couldn’t seem to get this one section as warm as the rest of the house.

If he ran the boiler long enough by raising the thermostat, it would get warm, but the rest of the house was like an oven. He sounded very frustrated, so I agreed to meet him at the job.

This part of town is known for its large houses and fund-raising visits by President Bush. Many of the houses were built in the glory years of steam heating — big society shacks with big steam boilers. This joint had the longest driveway I’ve ever had the privilege to drive up. It was at least a half-mile of smooth asphalt winding along a wooded ridge and over two gorgeous stone bridges.

When the house finally came into view, I could see my contractor friend and the caretaker looking up to the roof. A huge oak tree had been hit by lightning and crashed a large limb right on a very ornate chimney, the kind that twists around and costs more than my house to repair. Oh yeah, and the slate roof and copper gutters would also have to be repaired. Ouch!

The troubleshoot

We went inside and met the lady of the house. She was surprisingly interested in the operation of her steam system. She even came down to the boiler room with us. The first thing I like to do is familiarize myself with the system piping, so we all trekked around the basement looking for the end of steam mains, tracing wet and dry returns and looking around.

I was having trouble finding the end of the steam main for the area of the house that wasn’t heating right. The four of us were standing in a large bath just off the billiard room. I asked the caretaker if there were any rooms left to see. He looked at the lady of the house. She looked back at the caretaker, then looked me up and down, looked at the contractor and looked back at me. She reached up behind her in the linen closet. I heard a buzzing sound and the caretaker swung open a full-length mirror like a door.

“Ten years I’ve been working here and you never showed me this,” the contractor said.

We stepped through the passageway behind the mirror/door into a vault-like room with a bank safe and cases of liquor, wine and beer. There was enough hooch to get an army division plastered. I looked up to find the end of the steam main I was searching for and, sure enough, there was the problem. This was a two-pipe system that used radiator-style thermostatic traps at the end of the steam mains to vent the air over to the dry returns, which then carried the air back to be vented in the boiler room. Unfortunately, someone years ago had removed the trap and capped off the connections to the steam main and dry return.

Who knows why? Whatever the reasoning, it was the wrong thing to do. This steam main without a vent was pooling air at its end, thereby blocking the flow of steam up the risers to the radiators. Steam pushes air ahead of it as it moves through the system. The air from the main had to find its way out through the radiator traps, a much slower process. Consequently, steam reached these radiators after the radiators in the rest of the house were warm. When the thermostats were satisfied, these radiators hadn’t received enough steam to do their job.

The follow-up

I explained to the crowd in the secret room that a new trap would have to be installed to act as the air vent for the end of that steam main. With the air removed from the end, steam flows evenly up the risers. The lady of the house seemed to understand. The caretaker cussed the caretaker who worked there before him. The controls guy was still mad that he wasn’t allowed in here the past 10 years. I just enjoyed the whole thing, especially when the lady of the house reported later that her castle was never more comfortable.

It turns out that the owner of the estate was flush with cash. No need to worry about that storm damage.

The controls guy got to put in a new boiler with boiler feed unit. The caretaker, flush with time, got to replace the guts of every steam trap in the place. The supply house got to move a little inventory.

Patrick Linhardt is the sales manager at Aramac Supply in Cincinnati. His newly released book is “Linhardt’s Field Guide to Steam Heating.” To order, visit www.steamupairoutwaterback.com, or call 513/703-5347.

TAGS: Bath/Kitchen