This week we’re hosting the Image Permanence Institute as part of their research program on energy savings opportunities in libraries. I’m tremendously excited about the work, which is preservation in every sense. The goal is to maintain or improve our preservation environment while reducing the amount of energy required to create that environment. One of the keys is, of course, reducing or ceasing use of HVAC equipment at optimal times.
This can seem paradoxical, but as we learn more about the way our materials respond to environmental changes and as we have more raw data from our digital building controls, data loggers, and weather history, it is becoming possible to chart a better path. I’ve written a little bit about this on the blog and you can expect more as the project develops.
All the glossy science aside, though, yesterday we were in the machine rooms coming to grips with the design intentions and as-built and -running state of our mechanical systems. This is what preservation really looks like.
This is a set of cold water supply and return lines in the SRLF, our primary storage facility. Just about everything else we do in preservation and conservation is dependent on having enough cold water to chill the coils that are used to reduce the air temperatures in out HVAC systems and then being able to take that water out to a cooling tower to scrub off its heat load.
Here’s the Trane unit that’s attached to those lines, distributing water out to the air handling systems.
This is the pre-treatment system and air distribution system for the second module of the SRLF. The two blue pipes connect to the cooling coil that sub-cools the outside air to reduce its dewpoint and, in turn, condense out moisture. That lets us keep the air in the SRLF cool and dry. The second system, in the background of the photo, is a mixed air chamber that collects return air from the SRLF, mixes it with outside air, recools or reheats the mix as needed, and then pushes the treated air out to storage.
When we found the system, its mixed air chamber was wide open, however. That entry is the big open grate in the background of the picture; it’s a fire damper that should be closed in normal operation. As it was, the air was being short circuited and we were loosing the energy efficiency of recycling the return air as well as the benefit of pre-treating the outside air. We’ve since closed that and our facilities team is checking the control components to isolate the cause of this problem.
To give a sense of scale, here’s a photo of Jim Reilly, Director of IPI, and (some of) Peter Herzog, our consulting engineer, inside the mixed air chamber.