The two main boilers for the boiler system are located in the janitor’s closet in the basement of the school.
As you’re walking into your first period class of the day, you notice that the classroom feels a little warmer than usual, but the temperature is perfect after walking into the school from your car in 30 degree weather. After sitting down at your desk, you notice one of your classmates leaning over a big metal rectangle the same color as the wall that appears to be blowing out air. You ask your classmate what they’re doing, and they tell you that the metal rectangle they’re standing by is a univent, which blows out warm air from the boiler system that heats the school.
The boiler system works by heating water stored in two large tanks, known as boilers, using natural gas. Once the water is heated, steam and hot water travel through pipes that run throughout the building to univent systems located in the rooms and hallways throughout the school. The unit ventilators, or univents, then transfer the heat from the hot water into the air in univents by moving air in between the connected rows of pipes hot water travels through, heating the air. The heated air is then blown out of the univent by a fan and circulated throughout the room. After the hot water travels through the connected rows of pipes, the water starts to cool as it moves back to one of the boilers, signaling the start of the process over again.
Once the school’s boiler system is turned on, it can’t be turned completely off until temperatures rise again at the end of winter or the beginning of spring when the school begins to transition to cooling. Tom Frase, a janitor at the high school, believes in the ability of the school’s boiler system to heat the school no matter how cold it gets outside.
“It’s very efficient. Even when it was down to 20 below, it was still warm in the school,” Frase said. “The only bad thing is when it’s hot and then it gets really cold and they turn it on… you can’t turn it off from that point.”
Since the boiler system can’t be turned off, it’s turned on at different times from year to year based on the weather to ensure the school stays at an ideal temperature. Trent Kelly, the Director of Technology and Operations for HPS, as well as a few other maintenance people, decide when to turn the boilers on. The boilers are normally turned on when temperatures reach 35 and below in the evening and don’t rise above 50 during the day for three or four consistent days, however if there’s precipitation when the temperature is in this range, the boiler is turned on sooner since having a lot of moisture in the air tends to make people feel colder than the temperature actually is. Even if temperatures rise again after precipitation, the boiler is still typically turned on to prevent rooms from becoming too cold before the system is turned on. This year, the boilers were turned on in late October which is on the earlier side compared to when the system is typically turned on with the first week of December being the latest the system has ever been turned on.
“Like this year, we had a few rooms, not a lot, but we had a few rooms that were in the 62 to 64 range, and at that point we’ve got to start heating those rooms up,” Kelly said. “We just try to make sure that we’re going to watch the weather as close as possible.”
Even with the school being about 315,000 square feet in total, the boilers are able to keep the school warm even when temperatures drop, however when temperatures are cool in the morning and warm up in the afternoon, water is heated in the morning to warm up the cool rooms, but in order to prevent the building from becoming too warm when temperatures rise in the afternoon, the system is turned off. The only problem arises when although the water stops being heated, the heat from the water in the system that is already warm still has to dissipate, which can cause the building to heat up too much.
“So it’s pretty efficient for heating that much space, and the boiler works very well when temperatures are cold on a consistent basis, but the problem is when it’s cool in the morning the boiler has to heat up to 120 to 140 degree water because that’s what goes through the system,” Kelly said.
Trent Kelly and the other members of the maintenance crew are trying something different with the boiler system this year in hopes of preventing classrooms from getting too warm in the afternoon when temperatures vary throughout the day.
“The boiler turns off much earlier than it did before, so we try to turn it off and I think it has kind of helped this year,” Kelly said.
The boiler system the high school uses today is the same one that was installed when the school was built in 1955. The high school also uses newer technology to make sure the school remains at a fairly consistent temperature, including a computer system that shows the temperature of all the rooms in the high school as well as the history of the temperatures in each room.
“It’s an older system, but it’s an efficient system,” Kelly said. “There’s just little quirks and little things that you have to watch, and for the most part teachers and students understand that it’s going to be maybe a little cool in the morning if I don’t turn it on, but then it might be a little warm in the afternoon if I do turn it on, so it’s a balancing act, but overall I think it’s a pretty decent system.”
