Two commercial water-source heat pumps have been added to the company’s product line — the Aston Compact and the Arbor Base — and upgrades have been made to the Arbor Series. The Aston Compact offers efficiencies of 3.7-4.8 COP and 18-30 EER. Available in capacities from 0.75 to 6 tons, the unit features the Aurora generation of communicating controls and a variety of options, including a factory-installed 24-V motorized on-off water valve option for variable-frequency drive (VFD) pumping with automatic internal water flow control and hot gas bypass. The Arbor Base has a compact design, high-efficiency operation (3.3-3.5 COP and 15.6-17 EER) in a 0.5- to 6-ton unit. Like the Aston Compact, the Arbor Base uses environmentally friendly R-410A refrigerant. Both units can be used for retrofit and boiler/tower applications. Upgrades to the Arbor Series include the addition of Aurora communicating controls and a five-speed electronically commutated motor (ECM) blower motor option; the latter is an option that joins the high-efficiency permanent split capacitor (PSC) motor and variable-speed ECM options previously available.