Key Points
- Regular rooftop unit maintenance can significantly reduce your summer energy costs.
- Change filters regularly. Check for air leaks and improper refrigerant levels and fix them accordingly.
- If it’s time to upgrade, check with Pacific Power for cash-back incentives for high-efficiency equipment.
Packaged rooftop units provide heating and cooling to all types of commercial buildings. They operate in harsh outdoor environments and since they are located up on the roof, they are easy to forget.
This lack of attention can be costly. Poor maintenance can lead to unnecessary repairs, shorten equipment life, and reduce system efficiency. While the primary purpose of a good preventive maintenance program is to optimize overall system performance, the following practices will help lower your summer energy bills:
- Change filters regularly. Dirty filters block airflow and reduce the efficiency of the system, as well as building comfort. Switch out air filters in the unit every season and replace filters inside the building every month between service calls.
- Clean evaporator and condenser coils. Dirt on the evaporator coil degrades airflow, reducing cooling capacity. A dirty condenser coil raises the condensing temperature, which increases power consumption. Clean coils regularly using soap and water; a specialized cleaning solution may be necessary if the coils have been left unattended for some time.
- Fix air leaks. Air leaks in the cabinet and supply ducts waste conditioned air, reducing system efficiency and occupant comfort. Leaks are a particular problem on the supply air side, where high pressure can force a significant amount of air out of a tiny gap. Inspect for leaks and take corrective action, such as replacing screws, latches, or gaskets.
- Adjust and clean dampers. Dampers provide free cooling at the right temperature. However, if they are stuck open they can waste energy by bringing in hot outside air. If the unit has a damper, clean and lubricate it properly. Also, cycle run-through to ensure the actuator, dampers, and temperature sensors are operating correctly.
- Check refrigerant level. Improper refrigerant charge lowers compressor operating efficiency. In an overcharged system, refrigerant backs up, making the compressor work harder. If the unit is undercharged, the cooling capacity is reduced. Undercharging typically results from a leak in the system, which should be found and repaired as quickly as possible.
Don’t take shortcuts when maintaining your rooftop unit. Small perceived savings now actually will cost you more over the long term in higher energy bills and equipment repairs. If it’s time to upgrade, visit Pacific Power’s website to learn more about wattsmart® cash incentives for high-efficiency cooling equipment.
This article previously appeared in the Pacific Power Business Solutions Toolkit newsletter and is used with permission.
