Energy-Smart Maintenance for Schools

Schools have a variety of diverse spaces — classrooms, laboratories, gymnasiums, kitchens and sports fields — that make managing energy use a challenge. HVAC, plug loads and lighting are the largest users of electricity in school facilities. Continuous maintenance is critical to keeping energy-using equipment in all of these spaces operating reliably and efficiently. Here are some tips.

HVAC Systems

Cooling

On packaged rooftop units, clean the evaporator and condenser coils and air filters to ensure airflow is at full capacity. Check the refrigerant site glass as needed and be sure there are no leaks. Check the fan and belts. Ensure proper belt tension and recheck it to make sure it’s holding steady. Verify that compressor and fan motors are operating properly and without excessive vibration or heat.

For larger schools with chillers and cooling towers, inspect drive shaft couplings, cooling tower fill media, mechanical brakes/fan, and gearboxes. Make sure the filter media stays intact when you perform backwashing. Ensure that the water is free from debris, that spray nozzles are not clogged and condenser coils are clean. Inspect your air handlers and make sure your dampers can open and close without gaps.

Heating

Boilers are widely used in schools to provide space heating. Follow these nine maintenance tips to keep your unit operating at peak efficiency:

1. Insulate steam and hot water pipes with at least 0.5-inch insulation.
2. Remove scale from boiler tubes.
3. Check the burner flame. Blue flame is good, and yellow indicates incomplete combustion.
4. Check burner air-to-fuel ratio. Shoot for 10% to 15% excess air.
5. Tune damper settings on boiler draft fans.
6. Identify leaking steam traps and fix or replace.
7. Make sure boiler room ventilation requirements are met.
8. Check bearings and seals of water pumps.
9. Test boiler water daily and regenerate water softener when hardness exceeds 17 parts per million. This decreases deaerator ventilation rate and blowdown losses.

A tight and well-maintained building envelope is critical for comfort and efficient HVAC system performance. Inspect windows for cracked caulk or gaps around the edges; replace damaged and missing caulk. Make sure exterior doors seal tightly, and replace old or loose weatherstripping. Check for gaps between the foundation and walls, as well as around plumbing or wiring access to the outside. Seal with caulk or expanding foam.

Lighting

Optimizing efficiency while maintaining optimal light levels in diverse school spaces is a challenge. Follow these tips:

• Clean fixtures and lamps every six months.
• Replace lenses if they appear yellow.
• Clean or repaint indoor walls regularly. Dirt collects on surfaces, reducing the amount of light they reflect.
• Verify that occupancy and daylight sensors are working properly.

Use group lamp replacement, which saves labor and optimizes light levels. This can be especially helpful for outdoor light or in high-ceiling areas — like gymnasiums — where lighting maintenance can be challenging.

Plug Loads

Plug loads are anything that you plug directly into a wall. These devices often draw power whether they are in use or not. With some simple maintenance and operational practices, you can reduce energy waste.

• Enable power management “sleep” settings on all computers and office equipment.
• Supplement power management settings with advanced power strips that automatically shut off power to unused devices.
• Install occupancy sensors on cold-drink vending machines to shut off the compressor and front-panel lights when no one is present.

Electrical Infrastructure

Regular preventive maintenance on electrical infrastructure equipment — such as switchgear and transformers — is also critical for optimal reliability and performance.

Perform an infrared thermal scan on switchgear to detect hot spots that may indicate loose connections or short circuits. Remove dirt on de-energized equipment by wiping or vacuuming or compressed-air blowing.

For transformers, verify tank liquid level and check for oil leaks. Inspect bushings for cracks or chips. Perform a thermographic inspection of the tank, radiator, surge arrestors and bushings. Measure the dielectric value and/or resistance of the coil insulation with a megohmmeter. Conduct fluid tests per ASTM D3612 standard test method.