Replacing Commercial Rooftop Units

Replacing Commercial Rooftop Units

Commercial rooftop units (aka RTU's) can also be referred to as a package unit. The reason is that the RTU is a self contained system whereas all the components need to provide conditioned air is in one concise unit.

This means for either heat and air conditioning (split system) or just one of the two depending on the commercial need.

These package units are most commonly found in all kinds of commercial and industrial properties and applications. It very much resembles a large metal housed box or container with the needed components to accomplish the need of conditioning air for the occupants of the building below it. These components include an expansion device, the evaporator, a compressor and an air-cooled condenser.

Package rooftop units generally connect directly to the interior ductwork system that delivers conditioned air throughout the intended space and then it circulates to return air ducts back to the package unit.

Common Problems:

Unfortunately, when it comes to replacing commercial rooftop units, this can be an expensive endeavor. At some point, not even repairs can bring any real value to the system, since these repairs are more costly than just replacing the unit with a new and much more efficient package unit.



Interior Changes and Add-ons

Often times, your building may have been added onto or interior space changes have occurred which have caused your package unit to work harder than its needed to, to accomplish the desired temperatures in that space.

Along with this, the rooftop unit may now not even be sized correctly for the building and its occupants. A larger tonnage unit may be required as a solution to the problem. 


Efficiency of Old vs. New

Let's face it... as time goes on technology improves with all things HVAC. If your existing rooftop unit is more than 15 years old, it is time to consider newer package units that have better than standard efficiency. You may or may not need to consider a newer high efficiency unit. An older standard unit can consume more electricity and not be the best value in terms of per ton of cooling.


Existing Ductwork Issues

Quite often when we get called out to look at an existing rooftop package unit, we find that the existing connected ductwork has some issues that really place an extra load on the RTU. These issues range from unnecessary routing due to interior changes all the way to large un-connected gaps or air doors malfunctioning from different zones. Even electrical conduit that supports package unit can be a problem when interior changes occur. 


Outdated Equipment Configurations

All rooftop package units require different support configurations to operate efficiently and safely. Older electrical components can be a safety or fire concern if not properly rated for the current configuration. The support system for the structural load needs to be periodically inspected for safety and any signs of being overstressed. An internal leak of the rooftop unit can become a big problem with deteriorating structural roof supports.


Roof Curb Issues

The roof curb where the rooftop unit sits on and attaches to can even deteriorate over time. A roof curb evaluation may or may not be determined with the existing package unit in place. A proper seal and fitment to the new package unit is necessary if that is a path you're considering. Sometimes a new curb adaptor is necessary to accomplish a different sized or configured unit.


Control Units

The RTU requires a certain set of controls to operate and operate efficiently. Relays, timers, and boards become worn due to time in service, extreme temperature variations, humidity issues or even pest or water intrusion. These controls also have a need to support other ancillary devices and can become outdated over time due to newer, more efficient technologies.


Filtration Issues

Selecting the correct filtration and media is critical to overall efficiency of your RTU. Filtration options are generally bountiful and should require a maintenance program to maintain quality air. This also protects your equipment while meeting those indoor air quality requirements and budgets. These can be scheduled at the same time as an annual service plan to maximize efficiency and reduce overall maintenance costs.


Lack of Maintenance

This is a big one. Often times, the out of sight... out of mind scenario is a common issue with all sorts of rooftop HVAC units. One of the most common components that goes without its proper maintenance is the RTU condenser coils. These should receive attention at least annually.

Cleaning of the condenser coils and inspecting other critical components, maintaining correct oil levels, etc., assures efficiency while reducing electrical demands on the system.

These properly maintained components allow the unit to run cooler and as designed versus over-heating due to clogged coils, lubrication and/or refrigeration (Freon) issues. Annual service plans help reduce unforeseen and very expensive surprises to tender operational budgets over time.

When Replacing Commercial Rooftop Units:

Quite often, you can stretch your overall heating and cooling budget of package units or RTU's by employing a vigilant maintenance plan.


However as mentioned above in common problems, at some point, not even well planned maintenance and repairs can bring any real value to the system. It's better to move on to a newer, more efficient rooftop unit. Here are some valuable tips for when the time comes to replace a commercial rooftop unit.

Conducting a Package Unit Survey

Conducting a complete review and inspection of your rooftop unit allows for a more comprehensive report of it's current state of condition. This is also a great time to analyze system needs to determine if the correct sized unit is currently installed or if your needs have outgrown the current tonnage.

New top brands and features allow for the right equipment as well as holding down overall heating and cooling costs. Consideration of how the space is being utilized currently versus how it was originally when installed provides additional insights.

Compare Energy Efficiency Options

When replacing commercial RTU units, you have many choices. Choices of brands, warranty, standard efficiency or high efficiency.

Upgrading to high efficiency units can most often reduce overall costs per ton of cooling. When you schedule for a consultation, our factory trained specialist will analyze your options and fully explain the pros and cons of each system, type and brands available.

Connected Ductwork

During our analysis, we will look over and test your ductwork. We will also check the design of existing layouts and how this would best be optimized to reduce overall system costs while increasing efficiency and airflow in desired spaces.

Assess Equipment Configurations

Current electrical components may need to be replaced to support the desired commercial RTU HVAC unit. Supports for the new unit may also be necessary if the new commercial unit has increased tonnage for the required space. Ducting may also need to be adapted to fit the unit where return air configurations are different. Your B.I.M.S., Inc factory trained specialist will advise you of any of these configuration requirements beforehand so there are no installation surprises.

Roof Curb Evaluation

When possible, we will always try to exchange your new commercial rooftop unit with a similar sized unit so we can utilize your existing roof curb. This will generally save you money while providing for increased efficiency of a new package unit.

RTU Control Unit

Your new commercial package unit will include an all new control unit matched to the requirements of the rooftop unit. New controls and any ancillary devices will also become a part of the system. Together with any new smart controls including new generation smart thermostats allows for an optimized system so that you and your people can enjoy a much more comfortable space with quality climatized air.

New Filtration

When replacing commercial rooftop units, it is imperative to match correct filtration and media to provide all those that will be affected by the air the best in safety and health. We provide the best options available at the most competitive prices to bring you total satisfaction. Ask your B.I.M.S., Inc specialist about our annual service maintenance plans that include cleaning and/or replacing filtration media when needed.

Maintenance and Maintenance Plans

For the best in peace of mind, an annual maintenance plan may be your best option. In the end, these can be the most affordable way to keep your new commercial package unit performing at its peak while being easier on the budget.

Annual cleaning of condenser coils and inspecting, testing other critical components, maintaining correct oil levels, testing refrigerant, etc., assures efficiency while keeping the manufacturers warranty in check.

A properly maintained commercial rooftop unit allows your B.I.M.S., Inc service tech to conduct their annual service in record time and assures that your new unit will remain trouble free for years to come. These annual service plans help reduce unforeseen and more expensive service calls in the future especially during extreme outside temperature swings, which in turn keeps your operation running smoothly.

Call Us Today

Unsure if your existing RTU package unit needs repairs or a replacement? Then please don't hesitate to give us a call or request a service call. We can help you figure out the best course of action to take for your faulty equipment.

Schedule A Service Call or Consultation Today