Risks vs. Rewards
Optimizing is not without risks. The more you adjust your system, the more trouble you can get in. Here are some things to anticipate:
- When temperatures and humidity are allowed to swing, components expand and contract. For example, if hot water is supplied at 180 degrees F. in the morning and it cools to 90 degrees F. as outside temperatures climb, some contraction will occur. Ensure that the expansion tank can handle this change in volume.
- During chiller changeovers, ensure that a pump doesn’t run with all the water valves closed.
- More complexity requires more system monitoring and time to cover all the situations.
- Ensure that your equipment never short cycles.
- Watch for unintended operation of equipment.
Finally, remember that some adjustments may not make a big enough difference to justify the effort. Nevertheless, the results from the key adjustments are well worth it.
For more optimization suggestions, see my earlier article, “Drive Your HVAC System to High Performance” in BUILDINGS, August 2012.
J. Robert Howard is a Facility Manager Administrator, Certified Facility Manager, and LEED AP with degrees in aeronautical engineering and industrial engineering. He has written energy programs in ladder logic, Clipper, and a programming language used by a major controls company. A retired Air Force fighter pilot, he has more than 20 years of experience as a manufacturing engineer and a facility manager. He can be reached at firstname.lastname@example.org.