Church RTU installation by Abel
It’s time to dust the snow off your RTU and get it ready to switch over to cooling. RTUs can be the most efficient and cost effective HVAC systems, but, they must be properly maintained to get the job done.
Business Energy Advisor says:
Packaged air-conditioner and heat-pump systems, also called rooftop units (RTUs), fall into disrepair over time, leading to energy waste and compromised comfort for a building’s occupants. It’s crucial to maintain these RTUs on a regular basis to ensure that they cool buildings and occupants as intended without wasting energy. Regular maintenance will also help to prevent or quickly catch malfunctions before they have a chance to further degrade the equipment or waste prodigious amounts of energy.”
At Abel Heating & Cooling we Recommend Getting a Head Start
Here is a list of services your HVAC technician should perform with your preseason inspection:
- Check the refrigerant charge.
- Inspect and clean the evaporator and condenser coils.
- Clean and/or replace all filters as needed.
- Check the compressor’s oil charge.
- Clean and inspect inlet screens.
- Lubricate the fan motor bearings if needed.
- Inspect the blower belt for wear, proper tension, and pulley alignment.
- Check the condenser fan height.
- Inspect the evaporator fan to ensure that it is properly centered in the housing.
- If the unit has an economizer, perform a cycle run-through.
Rather than worrying about seasonal checkups, and scheduling, Abel offers the Abel Performance Program for both Residential and Commercial HVAC systems. This provides you with:
- Priority Service
- Thorough onsite evaluations
- Two to Four seasonal inspections annually
- Courteous, expert technicians
- Preferred pricing – and more!
Call us for information about the Abel Performance Program.
Fixing RTU Refrigerant Leaks
Low refrigerant charge compromises the efficiency and capacity of the unit. Consequently, you will need help. Here are some routine maintenance needs:
- Pipes can be wiped down to keep clean.
- Rubber-gasketed brass cap connectors need to be tightened.
- Leaks need to be looked for.
- A search is made for vibrating or rubbing pipes that can separate and leak.
- Repairing a leaking coil only needs to be done once, and the next time it should be replaced.
Several steps are required to repair a refrigerant leak, including nitrogen charging, refrigerant recovery, inspection with a leak detector, fixing the leak, a vacuum pull to meet EPA requirements, drying and recharging.
Again, these things need to be performed by a trained technician, and we offer this through our Performance Program, or checkup. (Click to see more)
The exterior of your unit is exposed to the elements, including heat, freezing cold, wind, snow, hail, dust and dirt. Therefore, your checkups should include an overall inspection of not only the interior parts, but the overall exterior.
Some RTU casings spill much of their expensive chilled air, or heated air, onto the roof, especially if the unit is poorly designed.
Panels that cover the RTU have many screws or fasteners and can make it frustrating to access and then close the unit. In fact, some other service technicians have been known to be lazy about replacing every one of the screws, leaving gaps. Even worse, improperly replaced screws can become stripped.
We’ve gone on calls where doors and panels have already fallen off, leaving the unit exposed to the elements. Snow or rain is blowing into the unit, energy is leaking, damage is being done to the electronics and components. This is costly for your business in utility and repair dollars.
At Abel we make sure our technicians have the proper tools to service and seal your unit/s.
Cabinet and Door Conditions
A loss of 200 cubic feet per minute can escape from a 10-ton rooftop unit under high pressure if there is just a small crack, and this reduces cooling and airflow by about 5%, again wasting dollars per year in energy costs.
The last step in maintaining the outer casing is to check the system to measure the airflow, insuring it is within the expected range of 350 to 400 cfm per ton of cooling capacity:
- Total static pressure drop measured across the fan.
- Shaft rotation measured with a tachometer.
- Flow from the manufacturer’s fan curve based on fan speed and pressure check, is recommended.
If the airflow is not within the correct range, but the cabinet is properly sealed, hence, a system investigation needs to be undertaken to find out why. Ducts could be leaking or blocked, dampers may not be set or performing properly, or the fan may be malfunctioning.
In conclusion, do you have questions? Are you thinking of adding or replacing a RTU? Are you ready for a spring checkup soon? Call us for more information at 952-472-2665 or Contact Us.