American Standard 8.5-Ton Rooftop HVAC Replacement in South San Francisco
Completed June 17, 2026
Replaced a rooftop heating and air conditioning unit estimated to be more than 20 years old with an American Standard 8.5-ton gas/electric packaged system. The new installation included an economizer for outdoor-air cooling when conditions allow.
Galaxy Heating & Air Conditioning replaced an aging rooftop HVAC unit at a property in South San Francisco. The customer estimated that the existing heating and air conditioning equipment was more than 20 years old and requested a replacement quote because they believed it had reached the end of its useful life.
We installed an American Standard 8.5-ton gas/electric packaged rooftop unit, model GDK102A3ELA3YXA. The new equipment combines gas heating and electric air conditioning in a single rooftop cabinet and uses a 208/230-volt, three-phase electrical supply.
The installation also included an American Standard economizer, model BAYECON355A. An economizer can use outdoor air to help cool the building when outdoor conditions are suitable, reducing the need for compressor-based cooling during those periods.
The completed project updated the property’s rooftop heating and cooling equipment while retaining a gas/electric packaged configuration.
Project details
Customer problem
The customer believed the existing rooftop heating and air conditioning unit had reached the end of its useful life. They estimated its age at more than 20 years and wanted a quote to replace the equipment.
Previous system
An existing rooftop packaged heating and air conditioning unit, estimated by the customer to be more than 20 years old.
Recommendation and why
We recommended an American Standard 8.5-ton gas/electric packaged rooftop unit with an economizer to replace the aging equipment.
The selected system provides both gas heating and electric cooling in one rooftop unit. The economizer adds the ability to take advantage of suitable outdoor temperatures for cooling, which can reduce compressor operation when conditions permit.
Equipment details
Brand: American Standard
Equipment type: Gas/electric packaged rooftop unit
Model: GDK102A3ELA3YXA
Nominal cooling capacity: 8.5 tons
Electrical supply: 208/230 volts, three-phase
Economizer: American Standard BAYECON355A
Installation location: Rooftop