8, 15 Ton Gas Heat Pump (GHP)


The Gas Heat Pump by Sierra is the latest model from Mestex to use an internal combustion engine, to power the AC's internal components instead of utility supplied electricity. The engine supports both Natural Gas and Propane configurations and has delivered electrical savings, both at time of construction and on a monthly basis, for hundreds of institutions nationwide.

The Sierra Gas Heat Pump offers three configurations for delivering BTUs to a building; either using a Daikin VRV® Air Handlers, Sierra Hydronic Heat Pump Energy Exchanger, or select Sierra DOAS models.

*VRV is a trademark of Daikin Industries, Ltd.

GHP Energy Exchanger - Air-Water Systems (AWS)


The Sierra AWS (Air Water System) Heat Pump Energy Exchanger enables the Sierra GHP to deliver BTUs via a buildings existing water systems. Retrofits of 2, 3 or 4 pipe and multi-zone hydronic heating and cooling systems start here. The exchanger enables select SpacPac, Dadanco Active Chill Beams, and Sterling Hydronic HVAC components are complementary products depending upon your implementation details.

GHP Variable Refrigerant Flow (VRF)


VRF (variable refrigerant flow) ductless and ducted air handlers are used with Sierra products to meet the challenge of heating and cooling by providing independent temperature control in multi-zoned buildings



The ZFR delivers high quality outside ventilation air for comfort and Indoor Air Quality in commercial buildings, with dehumidification, heating and filtration (up to MERV15) in a split system configuration. The ZFR allows engineers to satisfy load requirements more efficiently with higher ventilation rates while permitting conventional HVAC equipment to operate as originally designed.



The ZEC evaporative cooling system is one of the most environmentally friendly ways to improve working conditions and productivity. Evaporative systems can cool at 20% the cost of mechanical air conditioning. The innovative Turbo-CEL™ evaporative cooling media provides efficient cooling using water, not refrigerants, reducing your carbon footprint. Capacities up to 23,000 cfm are available.



The ZDF Direct Fired systems are flexible, cost-effective units for indoor or outdoor space heating, make-up air, and ventilation applications. Superior tube frame construction and stainless steel burners deliver decades of reliable service. The ZDF from Sierra can provide up to 16,000 CFM of warm, fresh and clean air to your building.

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