Recently I had the opportunity to spend time with a newly promoted chief facility engineer who was anxious to discuss what he could do to ensure a solid start — mainly the learnings that come from experience and contribute to successful facility management.
Our conversation proved to be quite timely, given the summer weather. I recommended performing a self-audit of the facility. Create your own checklist: preventive maintenance is one thing, but another set of eyes with a different agenda can go a long way to surfacing hidden — or perhaps overlooked — problems.
One of the most important areas to consider is the plant’s ventilation system, something that tends to be neglected until that first 90°F day when equipment overheats, doughs over-proof and employees find the environment untenable. First, ensure all the equipment is operating at standard; being idle during the winter can take its toll on belts, motors and drives. Inspection and lubrication will go a long way toward reliable performance throughout the summer. Check the integrity of protective screens, replace worn seals, clean and sanitize the housings and ducting, and replace all filters.
When replacing filters, if you are not using a two-stage system, consider modifying the intake and convert to one. Two-stage filtration — a disposable pre-filter that gets tossed away as it becomes ineffective and a Minimum Efficiency Reporting Value (MERV)-rated primary filter — is an excellent combination. Not only does this strategy improve efficiency in the removal of dust and other contaminants from your fresh air supply, but it will also save you money by extending the life of the MERV-rated filter.
Once the ventilation systems are running to standard and filters are changed, check the air balance and air flows. The plant should be slightly positive in pressure to the outside, and the air flow should generally be from makeup and packaging toward heat sources where it is exhausted. The air flow should also be directed at areas with the greatest concentration of line workers to create a comfortable work environment. If the plant is at negative pressure, or the air flows are misdirected, then rebalance the ventilation system to achieve those target conditions.
Next, look over refrigeration, freezing and cooling systems. Like the ventilation system, inspection and lubrication go a long way. An advantage to refrigeration systems is that a check of system pressures can indicate its operational condition. Change your filters, and clean all coils. Dirty condenser coils can cause a 30% loss in unit efficiency, which means a 30% increase in the electrical power consumed. Dirty evaporator coils have a similar loss in efficiency, but they also reduce air flow within the production unit. That can lead to extended cooling and freezing times. Those using glycol loops for mixer jacket cooling or chilled water systems should check the temperature differentials of both the supply and discharge steams against its design figures. If the efficiency is down, the exchanger may need cleaning. Now is also a good time to drain and flush ice bank systems and clean the coils if needed.
The compressed air system is vulnerable to the extreme summer climate. In the summer, there can be four to five times more water in the air than in winter. That certainly places an increased load on the air dryers. Check system pressures on refrigerated dryers to get a good sense of the unit’s health. Replace inline filters and ensure the drain system is cycling and functional. And, of course, clean the coils.
For desiccant dryers, check the regeneration cycle; the exhaust filter and muffler should not create back pressure as that can reduce filter efficiency. Lastly, make sure the ventilation system for the room where the compressor is located is functional and that filters/screens are clean, louvers are open, and fans are operational.
Don’t forget to inspect the roof so that membranes, stacks and ducting, and penetrations are all in good condition. Be sure to include a perimeter inspection of the structure. Look for moisture migration and ensure the building is tight (including masonry walls) and sources of moisture are eliminated. Dampness in the building will contribute to physical damage, environmental issues and affect equipment performance.
As the song goes, “Summertime, and the livin’ is easy.” Be sure that goes for your facility, as well.
