Designing for Efficient Operations and Maintenance
Mar 9th, 2010 | By Joe | Category: HVAC SystemsEnsure that all system components, including air handling units, controls, and exhaust fans are easily accessible.
To help ensure that proper operation and maintenance of HVAC system components will be performed, it is critical that the designer makes the components easily accessible. AHUs, controls, and exhaust fans should not require a ladder, the removal of ceiling tiles, or crawling to gain access. Rooftop equipment should be accessible by way of stairs and a full-sized door, not a fixed ladder and a hatch.
Label HVAC system components to facilitate operations and maintenance.
Labeling of HVAC components is an inexpensive and effective method for helping facilities personnel properly operate and maintain the HVAC systems. The labels should be easy to read when standing next to the equipment, and durable to match the life of the equipment to which they are attached. At a minimum, the following components should be labeled in each ventilation zone of the school and should correspond with the HVAC diagrams and drawings. “AHU” refers to any air handling unit that is associated with outdoor air supply.
- The number or name of the AHU (e.g., AHU ##, or AHU for West Wing)
- The outdoor air (OA), supply air (SA), return air (RA), and exhaust or relief air (EA) connections to the AHU, each with arrows noting proper airflow direction
- The access door(s) for the air filters and the minimum filter dust-spot (or MERV) efficiency (Air Filters, minimum xx% dust spot efficiency)
- The filter pressure gauge and the recommended filter change pressure (Filter Pressure, max 0.x in. w.g.)
- The access door(s) for the condensate drain pan (Drain Pan)
- Other pertinent access doors such as to energy recovery ventilation wheels or plates (Energy Recovery Ventilation Unit)
- The minimum amount of outdoor air for each AHU (### CFM minimum during occupied times)
- The outdoor air damper (OA Damper), with special marks noting when the damper is in the fully closed (Closed), fully opened (open), and minimum designed position (Min)
- If a motorized relief damper is installed (EA Damper), note the same positions as above.
- The access door to any outdoor air controls (OA Control(s)) such as damper position adjustments, outdoor airflow measuring stations, resets, fuses, and switches)
- Breakers for exhaust fans (Exhaust Fan ##), AHU, unit ventilators
- Access doors for inspection and maintenance of air ducts
- Any dampers and controls for air side economizers (as appropriate)
- The number or name of all exhaust fans, including the air quantity exhausted (EF##, ###CFM)
