CEAC-2021-02-February

(Continued from pg. 39)
“We also had an old absorber that was not being used since the
’80s that was also demo’d and removed,” Domina adds. “That was
a pretty big machine. That’s why these boilers are so big — because
it was feeding the absorber.”
After a lot of demolition and torch work, the DAY Scrap folks
were able to remove all of the hardware, and the install could
begin. One of the biggest advantages of going modular was the
ability to bring each of the Carrier units in through the standard
36-inch doorway that serves as the basement access. “We had a
power winch, and elbow grease for the rest of it,” Domina says.
Shipped fully factory-assembled with complete internal piping
and wiring, the chillers’ installation went smoothly, providing a
relatively painless transition to the newer technology. According
to Domina and Leitner, throughout the whole demo and install,
there were very few hiccups. “I’ve never seen a job go absolutely
perfect,” Domina says. “But as for the issues we did have, they
weren’t major headaches.”
There was perhaps one minor issue, Leitner indicates. “There was
a control issue [during demo]. They cut through a control line
and it threw an alarm up in the VAS system. We were able to get
the VAS company out, fix that, took care of everything.”
“We were able to find out where they were when they cut the
wire,” Domina recalls. “The building was only down for a little
bit. But once that happens, everybody starts freaking out, and
then you find it. As long as you’re not going two or three days
trying to find the problem. … But after that was said and done,
we’ve been running smoothly.”
The install was completed in the first half of 2020, and everything
has been up and running since. “We ran it this summer,
so we’ve gotten a good season out of it,” Domina says, adding
that the redundancy allows them the flexibility to only run some
combination of the units at any given time. “I think that’s the
best part about it, really — not running them all at the same
time, unless it’s very, very warm out, in the upper 90s. And even
then, it was still five at a time, or four at a time. So it held up really
well for the few 90-degree days we had over the summer.”
Having the ability to alternate which chillers are used on any
given day also saves on the general wear and tear of each unit.
“Essentially, you really have 12 stages, because of the two compressors
on each unit,” Domina continues. “They’re not all going
at the same time. One day one’s running, one day the next is
running, so they each get their usage, and their hours stay even
on each one. One’s not running more so than the other. … And
you’ve got the redundancy, too — if one fails, you’re still safe.”
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| Chief Engineer