American Cooling Technology unveils new AC condenser
The high-performance CR-4 roof mount condenser unit, at less than 10 inches tall, increases roof clearance and provides a cleaner, sleeker look to the air conditioning installation.


York, Pa.-based American Cooling Technology (ACT) recently released its new high-performance CR-4 roof mount condenser unit. The CR-4 further expands ACT’s existing North American product line, which includes a full range of split system air conditioning units and roof mounted units for school and shuttle buses.
Based on market feedback from customers who participated in field trials, ACT made the CR-4 unit smaller and lighter than competing high capacity roof mount condensers. At less than 10 inches tall, the low height of the CR-4 unit increases roof clearance and provides a cleaner, sleeker look to the air conditioning installation. The low profile and tapered leading edge of the unit eliminates the need to install a branch guard typically required on a standard rooftop condenser.
The CR-4 is available in both 12-Volt and 24-Volt and can be supplied as a dual loop unit to be connected to two automotive style compressors or as a single loop to connect to a single high capacity transit compressor. This flexibility makes the CR-4 a good fit for both conventional- and hybrid-drive buses.
By relocating the air conditioning condenser from the typical position under the bus floor to the roof of the bus, the capacity and operating efficiency of the air conditioning system improves because the system uses cleaner air from the top of the bus through the unit’s heat exchanger.
All ACT Split Systems use non-ozone-depleting HFC-134a refrigerant and the CR-4 delivers a high cooling capacity (165,000 Btu/hr. IMACA). It also is easier to install than its predecessors. The design specifications of the CR-4 unit include a one-piece “drop in” construction to dramatically simplify and reduce the time it takes to complete the installation.
In addition, the unit’s modular construction allows for improved access to internal components, making it easier to service. This translates to less downtime, which is critical for bus fleets operating on tight budgets.
ACT’s CR-4 rooftop condenser can be matched with other ACT components to provide a complete HVAC system that meets various vehicle sizes, duty cycles and geographic locations.
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