Troubleshooting systems is something I do on a regular basis. Sometimes it is over the phone. Sometimes it is at the job site. With the current state of the world, it is more over the phone. The phone can be a great tool, but it doesn’t always give you the big picture.
The problem with virtual boiler room visits is the guy on the other end of the call doesn’t know what I’m looking for. Generally, they are asking questions and I’m trying to give correct answers, but these questions and answers might not have anything to do with the problem.
If the title of the article looks familiar, it is also a song title from a London based rock/new wave group called “The Fixx.” They had some success here in the states in the early ‘80s. The song laments the fact that a girlfriend is giving misinformation and that one lie/thing leads to another lie. It’s more disco dance music than my favorite music, classic rock.
The job we are going to discuss in this article was like the song. The tech wasn’t lying to me, he was just giving me misinformation because he didn’t understand. One bit of bad information sometimes leads us to look in the wrong direction, which leads us to another… It is my job to clear up the confusion.
The guy putting in the boiler admitted that he doesn’t do a lot of boiler work. I get that and I always try to work with anybody until they have things working right. His first call complained about the new copper fin style boiler not working right and that the pressure seemed too high. He said the pressure was 40 pounds, which should be making a 30# relief valve release water all over the basement floor.
He assured me that the floor was indeed dry and would send a picture of the gauge via text message. The text is another technological advance that helps with virtual boiler room visits. In this case, as soon as I saw the text, I realized that the 40 pounds of pressure was actually 40 feet of altitude.
The gauge provided by the boiler manufacturer shows both pressure in psi and “feet H2O”, which means altitude, or how high the fill pressure can lift the water in the system. Basically, one pound pressure lifts water two feet, so his 40 feet H2O was just less than 20 psi, which isn’t going to pop the relief. Before I figured this out, we wasted time chasing a problem that wasn’t there.
No worries about that, but what is the problem with the boiler? He says that there is a lot of air in the system, so I ask him if he has bled the air out of the radiation. He says he has, but the system is making a “sloshing” noise, like there is a bunch of air moving around the system with the water.
He asks if the new pump could be too big, so we discuss that while I’m driving and can’t look up the pump curve. It is a three-speed pump, so I ask him to check it on the different speeds. He says it seems the same on any speed and then tells me about another pump in the system. If I was at the job, I might have noticed this, but with virtual, you get information as it is given.
He asks if both pumps are running, would they be too big? Simple enough to check by turning off the mystery pump, but the same sloshing sound. At this point I am wondering about the pumps location in the system in relation to the expansion tank. Air control problems can be solved sometimes (since nothing is absolute) by changing the location of the pump. I discussed this in an article last year titled Location – Location – Location.
When I asked him where the pumps were, he told me the new pump was on the return piping and the existing pump was on the supply piping. When I asked him where the expansion tank was connected, he said on the supply side, between the boiler and the existing pump. Maybe that doesn’t sound very exciting to you, but that got my attention.
We could test the theory of pumping away from the expansion tank to improve air control on this job without having to do any piping changes. I asked him to take the wires off the new pump and run the system with the existing pump only. If it was an air control problem, the sloshing sound should go away since the pump increases the pressure on the radiation side, which makes the air bubbles in the water smaller.
He called back after making the changes to report that the system was now quiet. On this job, theory and reality aligned to result in a system that functioned like we expected. But of course, the story, like the song, has a second verse. It couldn’t be so simple.
He called again to report that the building owner wanted him to move the new pump to the location of the existing pump. I told him that should be fine, just run the pump on the lowest speed, since that was close to the existing pump’s output.
He called again to report that he broke the pump flange gasket and could he get one in a hurry. I arranged for him to pick up a pair at our nearest branch. He called again to report that the new pump was making the sloshing noise in the new location. I may have muttered something that we can’t print here and decided that a site visit was required, so we set it up for the next day.
Then he called back to report that he found a few places in the baseboard piping that had high points without vents. I encouraged him to install vents at the high points or install a way to purge the air from that loop. He called the next day before our appointment to report that the system was working fine, now that those high points were free of air pockets.
As with a lot of troubleshoots, one thing leads us to another thing until we get the problem solved. Sometimes there are bumps along the way to distract you, but if you keep fixing the things you know are wrong, you will eventually fix the problem, either in person or virtually.
Patrick Linhardt is a thirty-five-year veteran of the wholesale side of the hydronic industry who has been designing and troubleshooting steam and hot water heating systems, pumps and controls on an almost daily basis. An educator and author, he is currently Hydronic Manager at the Corken Steel Products Co.