Guillermo D. Gonzalez Medina
Naperville,IL
Summary
HVAC Service and Installation Technician with experience diagnosing, servicing, and installing residential and light commercial HVAC systems. Skilled in electrical and gas component diagnostics, refrigerant charging, airflow systems, and system maintenance. EPA Section 608 Universal certified, and customer communication experience with equipment and maintenance sales.
Overview
9
9
years of professional experience
1
1
Certification
Work History
HVAC Service & Maintenance Technician
Cortina Heating and Cooling
Berwyn, IL
11.2020 - Current
- Diagnosed and replaced blower motors (1/4-3/4 HP), condenser fan motors, draft inducer motors, and compressors
- Diagnosed and replaced control boards, contactors, capacitors (7.5-80 MFD), transformers (24-360 VAC), breakers, switches, and outlets
- Troubleshot and repaired low-voltage (24VAC) and high-voltage (120-360VAC) electrical shorts
- Diagnosed and replaced ignition and safety components including flame sensors, hot surface and spark ignitors, gas valves, pressure switches, rollout switches, and high-temperature limit switches
- Performed maintenance and service on 80%-96% AFUE gas-fired furnaces
- Serviced and maintained rooftop units (RTUs)
- Serviced air conditioning systems including condenser maintenance, evaporator coil cleaning, and thermostat replacement
- Utilized superheat and subcooling calculations to properly diagnose and charge refrigerant systems
- Diagnosed refrigerant leaks and performed brazing repairs
- Maintained low-pressure and condensing boilers and tankless water heaters
- Diagnosed and replaced thermocouples, boiler pressure relief valves, and water heater gas valves
- Cleared clogged condensate drains and cleaned blocked chimneys
- Installed and replaced heavy-gauge steel chimney piping (3"-12" diameter)
- Performed basic diagnostics and service on heat pump and ductless mini-split systems, utilizing manufacturer technical support when required
- Serviced and repaired HVAC equipment from major manufacturers including Carrier, Trane, Lennox, Goodman, Rheem, York, and Mitsubishi
- Explained diagnostic findings, repair options, and system recommendations to customers
- Educated homeowners on system operation, preventative maintenance, and energy-efficiency improvements
- Assisted in the sale of maintenance contracts, furnace replacements, air conditioning installations, and repair parts
HVAC Installation Technician
Cortina Heating and Cooling
Berwyn, Illinois
11.2020 - Current
- Installed supply and return ductwork, insulated ductwork, flexible ductwork, vent grilles, dampers (6”–10”), and fabricated sheet metal duct adaptations
- Installed central air zoning dampers and zoning control boards
- Installed 80%–97% efficiency gas-fired furnaces and assisted with installation of condensing and low-pressure boilers
- Installed heat pump and ductless mini-split systems, including condensers and indoor heads
- Installed air conditioning condensers and evaporator coils (14”–24”)
- Installed 40–60 gallon gas water heaters and venting systems
- Installed gas piping for furnaces, boilers, and water heaters in accordance with code
- Installed PVC exhaust and intake piping (2”–3”), PVC condensate drains (3/4”), and condensate pumps
- Installed heavy-gauge chimney piping (3”–6”) for furnaces, boilers, and water heaters
- Ran refrigerant line sets (3/8” liquid; 3/4”–7/8” suction)
- Brazed copper refrigerant lines and filter driers using oxy-acetylene equipment
- Pressure tested systems with nitrogen, evacuated with vacuum pumps, and charged systems with R-22, R-32, R-410A, and R-454B
- Installed electrical disconnects (240VAC), conduit (1/2”), electrical whips, junction boxes, switches, outlets, and ran 240V circuits
- Installed new breakers (15–45 amp, single and double pole)
- Installed safety devices including wet switches and condensate overflow sensors
Host
La Josie
Chicago, IL
08.2019 - 09.2020
- Managed reservations and walk-in seating for a two-floor restaurant serving 200-300 guests per shift
- Utilized the Resy/Toast reservation system to coordinate table assignments based on party size and server availability
- Answered phone calls, assisted with reservations, and responded to customer inquiries
- Greeted and assisted guests and occasionally handled carry-out orders
Busser / Carryout & Cashier
El Solazo
Chicago, IL
05.2017 - 06.2019
- Cleared, cleaned, and reset tables
- Assisted with carry-out and cashier duties, including phone and walk-in orders, payment processing, and order packaging
- Maintained cleanliness and organization of dining areas, restrooms, and service stations
- Restocked beverages, supplies, and assisted servers throughout shifts
Education
High School Diploma -
Gurdon S. Hubbard High School
Chicago, IL05-2019
Associate of Applied Science - HVACR
Kennedy King College
Chicago, ILSkills
- HVAC electrical and gas diagnostics
- Soldering copper plumbing piping and fittings
- Brazing refrigerant lines using oxy-acetylene equipment
- Bending and forming copper refrigerant line sets
- Refrigerant charging and diagnostics
- Superheat and subcooling calculations
- Low-voltage troubleshooting
- High-voltage troubleshooting
- Furnace installation and service
- Boiler installation and service
- RTU installation and service
- Central air conditioning installation and service
- Ductwork installation
- Ductwork insulation
- Airflow zoning systems
- Condensate drainage systems
- Safety controls
- Customer communication
- Maintenance agreement
- Bilingual (Fluent English/ Spanish)
Certification
EPA Section 608 - Universal Certification (Type I, II, III)
Languages
English
Native/ Bilingual
Spanish
Native/ Bilingual
Accomplishments
International Baccalaureate Diploma
Timeline
HVAC Installation Technician
Cortina Heating and Cooling
11.2020 - Current
HVAC Service & Maintenance Technician
Cortina Heating and Cooling
11.2020 - Current
Host
La Josie
08.2019 - 09.2020
Busser / Carryout & Cashier
El Solazo
05.2017 - 06.2019
High School Diploma -
Gurdon S. Hubbard High School
Associate of Applied Science - HVACR
Kennedy King College