by Rick Stryker, P.E.
In October of 2005, "Building Principles" looked at a budding
project to replace the hot water heating system in a camp kitchen. Way
back then, I promised that we'd return to the story when there
was more to tell, so here's the "rest of the story" as
radio commentator Paul Harvey likes to call it. After a winter of wrestling
with the project, and a summer of operation, it's time to tell
you how it all came out in the end. If you can, break out that back issue
and read through the details. For those of you who don't archive
Camping Magazine though, let's revisit the high points.
The camp's kitchen needed a supply of hot water for food preparation,
as well as hand and dishwashing. The dishwasher units were configured
to sanitize the dishes at the rinse cycle with 180 degree water. The
existing system was a cobbled together collection of propane fired boilers,
a recirculating pump, and a leaky pressurized storage tank. The camp
was considering replacing the single boiler with three modern boilers
that the plumber believed had sufficient capacity, but the question of
hot water storage (a regulated pressure vessel) remained a big question
mark. The alternative was a technology called "tankless"
or "demand" hot water heating. The idea is that hot water
is never stored, but produced only when there is an open hot water faucet
(a "demand"). So instead of keeping water hot for hours with
nobody using it, energy is consumed only when there is a need.
But would it work? Originally, the plan was to use the summer of '06
to measure and record hot water and propane use. However, shortly after
the October ‘05 article was written, it became clear that the units
would have to be replaced before the next season,
or the kitchen would be out of business altogether. About that time,
everything kicked into a much higher gear.
Autumn 2005
Water samples were collected and analyzed to determine whether and how
much softening would be required. As it turned out, the hardness was
within the acceptable limits. No softening would be required at all!
Then we had to consult with the State agency that inspects boilers. In
Pennsylvania, that's the Bureau of Labor and Industries. It turned
out that there were several issues that we'd have to address before
they would approve such an installation. The most difficult would be
the requirement that the boiler design and construction had to be certified
by the American Society of Mechanical Engineers (ASME). Many client camps
in Pennsylvania avoid this requirement by purchasing several smaller
hot water heaters that individually do not exceed a certain heating rate.
For the tankless setup to work, the units which would deliver enough
hot water for the kitchen would exceed the limit by more than two times.
The units we had our eye on were not certified, and there was no intention
to pursue it. Back to square one: research the market. We found one manufacturer
which was within striking distance of meeting the requirement, but they
weren't sure how long the final process would take. It was November
and the clock was ticking. December passed and still no news, good or
bad.
Winter 2006
Finally, in the second week of January, we received word from the manufacturer's
representative that the equipment had its ASME certifications and that
these units would be on the market soon. How soon? "Maaaaybe late
spring or early summer," they thought. We couldn't afford
to wait until the last minute because even the conventional boiler equipment
took weeks or months to order and deliver, and then there was installation
time required. Using all of the information we had available, we worked
with camp leaders to develop a timetable and decision tree that established
a series of milestones that provided a preferred chain of events (installation
of tankless heaters) but which incorporated a fall back plan if the preferred
plan fell through. At the same time, we drew plans and prepared bid documents
for both alternatives so that we could put either plan into effect on
very short notice. By the time the snow melted, we were ready for [almost]
anything.
Spring 2006
In April, the supplier notified us that if we placed an order immediately,
we could have the units at camp in two weeks. Fortunately, our timetable
actually allowed four weeks, because in our haste, we actually ordered
and received heaters configured for natural gas and not propane. They
had to be returned to the factory (via standard freight!) and replacements
had to cross on the way. While this was happening, we were signing a
contractor to do the job and ensuring that his insurance was in order
among other administrative requirements. The right units arrived the
day before the contractor was supposed to install them. Luck? Sure! There
was some luck involved, but much more, it was our plan—thought
through and followed—that allowed things to work as they did.
Summer 2006
Countdown to camp! The week before staff arrived, the kitchen staff
came for precamp. Given the history of the hot water system, they were
pretty skeptical that something like this would work at all, let alone
meet the requirements of the inspectors. And briefly, it looked like
things might not work out like we'd hoped. Two issues vexed us.
The first involved reaching the required 180 degrees at the furthest
dishwasher. The system delivered temperatures of 175, 176, 177, and
even 178, but just not 180. The hot water distribution pipe was anchored
to a long run of concrete, cinder block, and steel surfaces. These
surfaces were wicking the heat from the hot water through the side
of the pipe. Much of the pipe was inaccessible without nearly demolishing
the building, so insulating the pipe wasn't an option. The cost
of running new copper pipe (as well as the time required to do it)
was more than we could stand. So ultimately, the answer was that one
of the regular vendors carried a line of equipment designed to deliver
a chemical sanitizing agent into the rinse water. The regulations allow
a much lower working temperature with such a system, and this also
removed the prospect of scalding the dishwasher operator. Two issues
solved at once!
The second situation involved a most mysterious behavior. The dishwasher
rinse temperature (or the hot water in any sink) would stabilize with seemingly
endless streams of hot water. Then suddenly, the temperature would drop
as if the heater had gone out. We spent the best part of the day troubleshooting
the heaters and brainstorming when we discovered that an improvised faucet,
made from a pipe tee and two gate valves, had been installed outside for
filling mop buckets. Any time that someone filled a mop bucket, hot water
was recirculating back through the cold water system through this connection!
By replacing the tee with a real faucet, the problem was solved, and the
mysterious temperature drop never happened again. The inspectors and the
kitchen staff were satisfied because there was ample hot water at the required
temperature. The caretaker was ecstatic because he spent no time messing
with broken pipes, leaks, or scalding recirculation systems. Functionally,
the system was a tremendous success. The acid test now would be whether
the systems had actually saved any fuel and money as promised by the manufacturer
and the calculation estimates.
Fall 2006
After some fairly quick data gathering, we were able to calculate that
fuel consumption had dropped 25 percent from the previous summer. Since
no other changes had taken place, the difference could only be attributed
to the new hot water heating system. But there was more to the story than
just the fuel savings. Let's look at what the camp's innovations
provided in hard dollars in Figure
1.
At first glance, it may seem that choosing the tankless heaters was
a no-brainer since the equipment cost was about one third of the cost
of the conventional boilers. But it's important to bear in mind
the risk, planning, and management that were required to make everything
come out alright in the end. The inspecting agency had to divulge the
criteria (ASME certification) that would be required for them to accept
the units. We had to find a manufacturer that could meet that specification,
and then follow up until they could provide it. We had to locate a
supplier who would stand behind the units in this application (new
for them also!) as well as a contractor who felt confident installing
them. Then we had to troubleshoot the system until we could find the
cause for things to not operate as we had planned. Any of these obstacles
could have derailed the project. But none did because of the forethought
and careful planning that went into every step along the way. Certainly
there were anxious moments as milestones were approaching, but still
the time line provided a well-thought-out plan would allow camp to
open on time.
When it was all said and done, what did camp gain and how did those
gains come to be? The most important step was being pro-active rather
than re-active. By taking the bull by the horns, the leadership was able
to manage rather than be managed by the situation. There was enough
time to look for alternatives, enough time to develop a time line which
planned for things to go awry, and enough time to adjust the plan along
the way. Get out of reaction mode by looking around camp with a new
eye. An opportunity to save big bucks might be right around the corner!
Originally published in the 2007 May/June
issue of Camping Magazine. |
