Dr-Fix-It! Notebook Archive:
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| Flame-Outs Happen . . . In the stillness of the night, the telephone seemed to sound ten times louder than ever before. Confused and startled, John bolted upright in bed, not yet understanding what had happened. The telephone rang a second time. John's mind focused and sleep began to wane. John picked up the receiver, "Hello ?" The voice on the phone said, " John, It's Herbie at the front desk. Sorry to wake you." John rolled over and sat on the edge of the bed, "Herbie, you lie." "Whaddya mean?" "You are NOT sorry to wake me. . . " Herbie Chuckled, "Eh, eh. . . Well, So far; I have eight rooms complaining that it is too cold inside. I am working with a little space heater to keep my feet warm and the lobby is down to 57 degrees." John yawned. "Well, those are all water-source heat pumps. There is no way eight rooms AND Admin AND the lobby would all take a dump at the same time. Most likely it's a central plant problem like the pumps or the boiler . . .' Herbie couldn't care less about the technical aspects of heating a building. "Well, whatever. . . All I know is it's cold here." "On the way". "Thanks, John" John parked his truck at the loading dock and proceeded straight to the boiler-room. He made a quick check of the room: First, all the pumps are running. "That's good", John reassured himself. Second, The condenser water temperature is 42 degrees. "Oh, that is way too cold. No wonder the heat pumps aren't working", John muttered. John turned the flame control switch to the 'off' position and noted the time. Then, he took a little walk around the boiler. It was just a little Ajax Boiler. Rated at 1.6 million Btu 's output . That is pretty small as commercial boilers go but still a respectable little boiler. Pressure at 25 PSI - the same as the water pump's suction pressure. "That is good". Low water cutoff is OK. "So, the boiler is full of water - probably". John lifted the lever on the pressure/ temperature relief valve. The water flowed to the floor drain. No air, John noted. "That confirms the boiler is full of water". A quick check with a flashlight and an inspection mirror in the draft hood confirmed that the flue was clear. John checked his watch. It had been five minutes since he had turned off the flame control switch. "I guess its time to try a re-light", he said to himself. John flipped the boiler flame control switch to the 'on' position. The Honeywell Flame Control on the side of the boiler sang its familiar song: 'Hum - click', 'tick', 'snap', 'woof '. 'Hum - click': The pilot solenoid valve opens and the spark ignitor is energized. 'Tick': Flame is proven and the flame safeguard relay pulls in. 'Snap': Main valve opens. 'Woof': Main burners light. John confirmed the results out loud, "Temperature rising, pressure rising. Everything looks fine". John shook his head and muttered to himself, "Oh great, Mr. Ajax Boiler, You got me out of a warm bed to come down here in the middle of the night and YOU WORK JUST FINE." John walked over to the phone, picked up the handset and dialed '0'. "Good Morning. Front Desk. Herbie speaking. How may I direct your call?" "Herbie, Its John. It was the boiler. It's running now. It should start to warm up pretty soon. "Aye, Aye, Scotty!", Herbie joked. John suspected it would be a long night in the boiler-room tracing down an intermittent flame failure. Any troubleshooter will attest that an intermittent problem is the hardest problem to repair. John wondered if there was some perverse force in the universe that makes certain machines operate flawlessly in the presence of a repairman only to return to their flawed ways once the repairman turns away. But, for now, the important thing was to get the condenser water back up to operating temperature. The boiler was running, for now. John only needed to find out why it failed and prevent it from failing again. . . It was midmorning by the time John closed the boiler-room door behind him. He stopped by the Admin Offices to pick up the mail then he headed downstairs to the engineering offices. John was listening to his voice-mail messages when Carlos, the Maintenance Foreman, popped in the office. "Carlos", John said, "I think I am going to go home. You take it for the day. OK?" Carlos rolled his eyes. "Oh, I would like YOUR job! Just stroll in, read your mail and call it a day!" "Carlos", John started slowly," If anybody's asking, I've been here since . . ." ". . . Yes, I know." Carlos grinned, "Just giving you a hard time. I talked to Herbie this morning. He said you were here almost all night. Did you get the boiler figured out?" John shook his head, " Not really. The boiler flamed-out once but it worked perfectly for me the rest of the night." "I hate when that happens. . .", Carlos interrupted. John continued, ". . . I checked the flame control out top to bottom. I did every procedure in the manual. I cleaned the pilot assembly. I sanded the flame rod and the ignitor rod. Cleaned everything. Made sure all the grounding was intact." Carlos shrugged, "Sounds like you did it all, John. Don't knock yourself out over it. Flame-outs happen." John nodded, "Yah, but as long as I am so rudely yanked out of bed, I would like to be sure the problem is fixed so I don't have to come down here again some other night". " You know, John," Carlos reassured, "With the way that boiler uses bare metal conductors with no insulation for the spark rod and the flame rod, all it is gonna take is a little bit of ANYTHING to mess up the flame sense circuit. Dirt or rust on the outside of the flame rod. Moisture. I've even heard that a SPIDER WEB will short out a flame sensor. I can believe it . . . We're talking 2 MICRO-AMPS. That's a pretty weak current. Almost no current at all !" John pushed back in his chair and yawned, "Yah, I have heard that spider web story, too. I've never seen it happen though. I think it is a myth." John stood up and started toward the office door, "Take it from here, Carlos. I'm going home" In the Boiler-room, a black widow spider cautiously emerges from her emergency hiding place in a crack in the floor. The room is finally still again except for the usual mechanical vibrations she has come to accept as normal. She carefully makes her way to where her destroyed home used to be; a web spun between the flame sensor rod and the bottom of the boiler. It has been a good location for her. The area is always warm and dry. Lots of flying insects are drawn to the location by the firelight of the boiler. She will need to capture a lot of flying insects soon because it is time to start laying her eggs . She begins the chore of spinning a brand new web. . . 2004.02.16 |
