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HVAC Services for Heating and Cooling – Oak Park, IL

Any time your air conditioner or heater stops working, life is interrupted. Not only is it uncomfortable to be too hot or too cold in your home, but it can also be dangerous. It’s important to have someone you know you can trust to promptly repair your HVAC in Oak Park, IL.

Deljo Heating, Cooling & Plumbing has been servicing the greater Chicago area for over a decade and has earned the trust of countless homeowners. We are proud of the reputation we have built, and we intend to continue the service we are known for.

HVAC Services in Oak Park, IL

HVAC Maintenance Services

Regular maintenance of your heating and cooling system is essential for continued efficiency and longevity. We recommend biannual service during spring and fall to ensure your HVAC system will work reliably throughout extreme high and low temperatures. Our HVAC technicians will inspect, test, and clean your system, replacing worn parts. We will make sure everything is working efficiently before leaving your home.

HVAC Repair Services

Whether you need AC repair, furnace repair, or anything in between, our technicians have the experience and knowledge to diagnose and repair any heating or cooling system. We arrive promptly for your appointment, remain professional and respectful of your time and home, and fully address all questions and concerns you may have.

If for some reason part of your HVAC system is beyond repair, we will discuss your needs and together decide how to proceed.

HVAC system repair in Oak Park, IL

Air Conditioning and Furnace Installation

Dejo Heating and Cooling can install any type of boiler, furnace, heat pump, AC unit, or dual system you may need. If you are ready to upgrade but are unsure what system is best for your home, we would be happy to discuss your needs and budget and make a professional recommendation you feel confident with.

Our team works quickly to ensure your timely return to comfort. Our goal is your satisfaction, and we take that very seriously.

HVAC Services in Oak Park, IL

During the century Deljo Heating, Cooling & Plumbing has served the greater Chicago area, we have developed a high standard of excellence that’s promised to every customer, every time we visit.

We truly care about our neighbors, and we want you to be comfortable and safe in your home. That’s why we also offer emergency repair service, no matter what time of day or night. Experience the Deljo Difference yourself, and rely on us for all your HVAC service needs.

Recent Jobs and Reviews in Oak Park, IL

Oak Park, IL at a glance

Deljo Heating, Cooling & Plumbing has completed 20 jobs in Oak Park, IL between July 2026 and September 2026.

The most recent job was on September 2, 2026.

Deljo Heating, Cooling & Plumbing has completed 116 jobs in Oak Park, IL in the last 12 months.

Job Locations and Reviews

Responded to no airflow complaint on 10+ year old air conditioning system. Upon arrival, confirmed outdoor compressor was running but indoor unit was not delivering conditioned air to living space. Measured supply air temperature at register showing 65.4°F, indicating inadequate cooling performance. Inspected attic installation and identified failed or disconnected supply duct at plenum connection. Flexible ductwork was found completely detached from main trunk line, causing all conditioned air to dump into attic space rather than reaching occupied areas. Reconnected supply duct to plenum and secured connection properly. Verified airflow restoration at registers and system operation returned to normal. Customer declined further repairs at this time.
Responded to no airflow complaint on 10+ year old air conditioning system. Upon arrival, confirmed outdoor compressor was running but indoor unit was not delivering conditioned air to living space. Measured supply air temperature at register showing 65.4°F, indicating inadequate cooling performance. Inspected attic installation and identified failed or disconnected supply duct at plenum connection. Flexible ductwork was found completely detached from main trunk line, causing all conditioned air to dump into attic space rather than reaching occupied areas. Reconnected supply duct to plenum and secured connection properly. Verified airflow restoration at registers and system operation returned to normal. Customer declined further repairs at this time.
Joe A.
Joe A. Checked in
Responded to no airflow complaint on 10+ year old air conditioning system. Upon arrival, confirmed outdoor compressor was running but indoor unit was not delivering conditioned air to living space. Measured supply air temperature at register showing 65.4°F, indicating inadequate cooling performance. Inspected attic installation and identified failed or disconnected supply duct at plenum connection. Flexible ductwork was found completely detached from main trunk line, causing all conditioned air to dump into attic space rather than reaching occupied areas. Reconnected supply duct to plenum and secured connection properly. Verified airflow restoration at registers and system operation returned to normal. Customer declined further repairs at this time.
Oak Park, IL 60302
Responded to callback for excessive noise from newly installed HVAC unit. Upon inspection, discovered loose electrical connection in control panel causing vibration and audible humming that intensified during operation. Secured wire connections with proper wire nuts, verified capacitor mounting, and tested system operation. Unit now running quietly with no abnormal sounds detected.
Responded to callback for excessive noise from newly installed HVAC unit. Upon inspection, discovered loose electrical connection in control panel causing vibration and audible humming that intensified during operation. Secured wire connections with proper wire nuts, verified capacitor mounting, and tested system operation. Unit now running quietly with no abnormal sounds detected.
Adrian M.
Adrian M. Checked in
Responded to callback for excessive noise from newly installed HVAC unit. Upon inspection, discovered loose electrical connection in control panel causing vibration and audible humming that intensified during operation. Secured wire connections with proper wire nuts, verified capacitor mounting, and tested system operation. Unit now running quietly with no abnormal sounds detected.
Oak Park, IL 60304
Completed full HVAC system replacement in residential basement mechanical room, including installation of new furnace unit with proper ductwork connections and plenum integration. Installed condensate pump, fan-powered humidifier, surge protector, and Ecobee thermostat to provide complete climate control functionality. All equipment properly mounted, vented with PVC piping, and connected to existing ductwork system with metal transitions, ensuring efficient airflow and system operation.
Completed full HVAC system replacement in residential basement mechanical room, including installation of new furnace unit with proper ductwork connections and plenum integration. Installed condensate pump, fan-powered humidifier, surge protector, and Ecobee thermostat to provide complete climate control functionality. All equipment properly mounted, vented with PVC piping, and connected to existing ductwork system with metal transitions, ensuring efficient airflow and system operation.
Andy A.
Andy A. Checked in
Completed full HVAC system replacement in residential basement mechanical room, including installation of new furnace unit with proper ductwork connections and plenum integration. Installed condensate pump, fan-powered humidifier, surge protector, and Ecobee thermostat to provide complete climate control functionality. All equipment properly mounted, vented with PVC piping, and connected to existing ductwork system with metal transitions, ensuring efficient airflow and system operation.
Oak Park, IL 60304
Conducted comprehensive evaluation of 24-year-old Carrier R22 air conditioning system with intermittently failing condenser fan motor. Assessed outdoor condenser unit housed in wooden lattice enclosure and inspected indoor ductwork and plenum assembly in basement mechanical space. Provided detailed replacement estimate for complete AC system upgrade due to obsolete R22 refrigerant phase-out and deteriorating condenser fan motor requiring full system replacement rather than repair of aging equipment.
Conducted comprehensive evaluation of 24-year-old Carrier R22 air conditioning system with intermittently failing condenser fan motor. Assessed outdoor condenser unit housed in wooden lattice enclosure and inspected indoor ductwork and plenum assembly in basement mechanical space. Provided detailed replacement estimate for complete AC system upgrade due to obsolete R22 refrigerant phase-out and deteriorating condenser fan motor requiring full system replacement rather than repair of aging equipment.
Michael C.
Michael C. Checked in
Conducted comprehensive evaluation of 24-year-old Carrier R22 air conditioning system with intermittently failing condenser fan motor. Assessed outdoor condenser unit housed in wooden lattice enclosure and inspected indoor ductwork and plenum assembly in basement mechanical space. Provided detailed replacement estimate for complete AC system upgrade due to obsolete R22 refrigerant phase-out and deteriorating condenser fan motor requiring full system replacement rather than repair of aging equipment.
Oak Park, IL 60304
Responded to service call for AC unit not cooling and making noise upon startup. Inspected outdoor condensing unit and found electrical connections at contactor showing signs of wear and outdoor exposure. Examined capacitor, contactor assembly, and associated wiring within electrical compartment. All wire connections were secured and terminals cleaned. Verified proper voltage and amperage at contactor. Capacitor tested within acceptable range. Unit cycled successfully with normal operation restored and noise eliminated upon startup.
Responded to service call for AC unit not cooling and making noise upon startup. Inspected outdoor condensing unit and found electrical connections at contactor showing signs of wear and outdoor exposure. Examined capacitor, contactor assembly, and associated wiring within electrical compartment. All wire connections were secured and terminals cleaned. Verified proper voltage and amperage at contactor. Capacitor tested within acceptable range. Unit cycled successfully with normal operation restored and noise eliminated upon startup.
Gerardo M.
Gerardo M. Checked in
Responded to service call for AC unit not cooling and making noise upon startup. Inspected outdoor condensing unit and found electrical connections at contactor showing signs of wear and outdoor exposure. Examined capacitor, contactor assembly, and associated wiring within electrical compartment. All wire connections were secured and terminals cleaned. Verified proper voltage and amperage at contactor. Capacitor tested within acceptable range. Unit cycled successfully with normal operation restored and noise eliminated upon startup.
Oak Park, IL 60304
Completed comprehensive cooling check on dual-zone HVAC system consisting of two air handlers and two condensing units per maintenance agreement. Performed electrical diagnostics including amperage readings on compressor and fan motors using digital clamp meter, verified all components operating within manufacturer specifications, and inspected refrigerant circuit connections and safety controls with all systems found to be functioning properly.
Completed comprehensive cooling check on dual-zone HVAC system consisting of two air handlers and two condensing units per maintenance agreement. Performed electrical diagnostics including amperage readings on compressor and fan motors using digital clamp meter, verified all components operating within manufacturer specifications, and inspected refrigerant circuit connections and safety controls with all systems found to be functioning properly.
Paul M.
Paul M. Checked in
Completed comprehensive cooling check on dual-zone HVAC system consisting of two air handlers and two condensing units per maintenance agreement. Performed electrical diagnostics including amperage readings on compressor and fan motors using digital clamp meter, verified all components operating within manufacturer specifications, and inspected refrigerant circuit connections and safety controls with all systems found to be functioning properly.
Oak Park, IL 60302
Performed comprehensive estimate for replacement of 24-year-old air conditioning system utilizing obsolete R22 refrigerant. Evaluated existing outdoor condenser unit and assessed current installation location, clearances, and refrigerant line configuration. Discussed customer's interest in relocating condensing unit to more optimal position and installing new refrigerant line set to accommodate modern equipment specifications and improve system efficiency.
Performed comprehensive estimate for replacement of 24-year-old air conditioning system utilizing obsolete R22 refrigerant. Evaluated existing outdoor condenser unit and assessed current installation location, clearances, and refrigerant line configuration. Discussed customer's interest in relocating condensing unit to more optimal position and installing new refrigerant line set to accommodate modern equipment specifications and improve system efficiency.
Jim C.
Jim C. Checked in
Performed comprehensive estimate for replacement of 24-year-old air conditioning system utilizing obsolete R22 refrigerant. Evaluated existing outdoor condenser unit and assessed current installation location, clearances, and refrigerant line configuration. Discussed customer's interest in relocating condensing unit to more optimal position and installing new refrigerant line set to accommodate modern equipment specifications and improve system efficiency.
Oak Park, IL 60304
Completed cooling check on two air conditioning systems. Replaced air filters with 16x20x1 and 16x25x1 filters, performed general service inspection, and conducted change-out-the-winter preparation to ensure both HVAC units are operating efficiently for the upcoming season.
Completed cooling check on two air conditioning systems. Replaced air filters with 16x20x1 and 16x25x1 filters, performed general service inspection, and conducted change-out-the-winter preparation to ensure both HVAC units are operating efficiently for the upcoming season.
Jay L.
Jay L. Checked in
Completed cooling check on two air conditioning systems. Replaced air filters with 16x20x1 and 16x25x1 filters, performed general service inspection, and conducted change-out-the-winter preparation to ensure both HVAC units are operating efficiently for the upcoming season.
Oak Park, IL 60304
Completed scheduled maintenance agreement inspection on residential split HVAC system consisting of condenser unit and air handler located in attic space. Performed comprehensive visual inspection of air handler control board and power supply components, verifying proper operation of all electronic circuits, connections, and safety systems. Documented equipment condition through photographic records showing control board assembly with intact heatsinks, toroidal inductors, wire harnesses, and digital display functioning normally. Inspected attic-mounted air handler installation, confirmed adequate clearances, proper insulation placement around unit, and verified all manufacturer labels and specifications were legible and intact for future reference.
Completed scheduled maintenance agreement inspection on residential split HVAC system consisting of condenser unit and air handler located in attic space. Performed comprehensive visual inspection of air handler control board and power supply components, verifying proper operation of all electronic circuits, connections, and safety systems. Documented equipment condition through photographic records showing control board assembly with intact heatsinks, toroidal inductors, wire harnesses, and digital display functioning normally. Inspected attic-mounted air handler installation, confirmed adequate clearances, proper insulation placement around unit, and verified all manufacturer labels and specifications were legible and intact for future reference.
Joe A.
Joe A. Checked in
Completed scheduled maintenance agreement inspection on residential split HVAC system consisting of condenser unit and air handler located in attic space. Performed comprehensive visual inspection of air handler control board and power supply components, verifying proper operation of all electronic circuits, connections, and safety systems. Documented equipment condition through photographic records showing control board assembly with intact heatsinks, toroidal inductors, wire harnesses, and digital display functioning normally. Inspected attic-mounted air handler installation, confirmed adequate clearances, proper insulation placement around unit, and verified all manufacturer labels and specifications were legible and intact for future reference.
Oak Park, IL 60304
Completed commercial HVAC maintenance agreement service on rooftop RTU cooling system, two water heaters with circulating and booster pumps. Replaced air filters including two 16x20x1 and one 16x25x1 units, performed system inspection and documentation of all equipment.
Completed commercial HVAC maintenance agreement service on rooftop RTU cooling system, two water heaters with circulating and booster pumps. Replaced air filters including two 16x20x1 and one 16x25x1 units, performed system inspection and documentation of all equipment.
Izzy G.
Izzy G. Checked in
Completed commercial HVAC maintenance agreement service on rooftop RTU cooling system, two water heaters with circulating and booster pumps. Replaced air filters including two 16x20x1 and one 16x25x1 units, performed system inspection and documentation of all equipment.
Oak Park, IL 60302
Responded to no-cooling complaint on newly installed Mitsubishi mini-split system. Upon arrival, verified electrical connections at disconnect box were properly terminated and system had successfully held vacuum during installation. Investigated 25-foot line set installation and confirmed refrigerant charge levels were at factory pre-loaded specifications. Conducted diagnostic testing of outdoor condensing unit and indoor air handler using manifold gauges to assess refrigerant pressures and system operation. Identified issue preventing cooling mode engagement and performed necessary corrections to restore proper system functionality. Unit tested and confirmed operating within manufacturer specifications upon completion.
Responded to no-cooling complaint on newly installed Mitsubishi mini-split system. Upon arrival, verified electrical connections at disconnect box were properly terminated and system had successfully held vacuum during installation. Investigated 25-foot line set installation and confirmed refrigerant charge levels were at factory pre-loaded specifications. Conducted diagnostic testing of outdoor condensing unit and indoor air handler using manifold gauges to assess refrigerant pressures and system operation. Identified issue preventing cooling mode engagement and performed necessary corrections to restore proper system functionality. Unit tested and confirmed operating within manufacturer specifications upon completion.
Izzy G.
Izzy G. Checked in
Responded to no-cooling complaint on newly installed Mitsubishi mini-split system. Upon arrival, verified electrical connections at disconnect box were properly terminated and system had successfully held vacuum during installation. Investigated 25-foot line set installation and confirmed refrigerant charge levels were at factory pre-loaded specifications. Conducted diagnostic testing of outdoor condensing unit and indoor air handler using manifold gauges to assess refrigerant pressures and system operation. Identified issue preventing cooling mode engagement and performed necessary corrections to restore proper system functionality. Unit tested and confirmed operating within manufacturer specifications upon completion.
Oak Park, IL 60304
Completed routine HVAC maintenance agreement service, including system inspection and replacement of 16x20x1 air filter. Verified thermostat operation and documented equipment condition with photographic records showing proper system functionality.
Completed routine HVAC maintenance agreement service, including system inspection and replacement of 16x20x1 air filter. Verified thermostat operation and documented equipment condition with photographic records showing proper system functionality.
Charlie B.
Charlie B. Checked in
Completed routine HVAC maintenance agreement service, including system inspection and replacement of 16x20x1 air filter. Verified thermostat operation and documented equipment condition with photographic records showing proper system functionality.
Oak Park, IL 60304
Completed cooling check on two condenser units as part of scheduled maintenance agreement. Verified system operation, measured supply air temperature at 13.5°F split across vent register, and inspected blower wheel assembly for cleanliness and proper function. All components operating within normal parameters with no deficiencies noted.
Completed cooling check on two condenser units as part of scheduled maintenance agreement. Verified system operation, measured supply air temperature at 13.5°F split across vent register, and inspected blower wheel assembly for cleanliness and proper function. All components operating within normal parameters with no deficiencies noted.
Alan M.
Alan M. Checked in
Completed cooling check on two condenser units as part of scheduled maintenance agreement. Verified system operation, measured supply air temperature at 13.5°F split across vent register, and inspected blower wheel assembly for cleanliness and proper function. All components operating within normal parameters with no deficiencies noted.
Oak Park, IL 60302
Responded to system fault high humidity alert on recently installed thermostat. Accessed fan coil airflow settings and adjusted dehumidify parameters from high to comfort mode. Verified supply air temperature at air handler reading 55°F, confirming proper system operation and resolving the false humidity warning.
Responded to system fault high humidity alert on recently installed thermostat. Accessed fan coil airflow settings and adjusted dehumidify parameters from high to comfort mode. Verified supply air temperature at air handler reading 55°F, confirming proper system operation and resolving the false humidity warning.
Izzy G.
Izzy G. Checked in
Responded to system fault high humidity alert on recently installed thermostat. Accessed fan coil airflow settings and adjusted dehumidify parameters from high to comfort mode. Verified supply air temperature at air handler reading 55°F, confirming proper system operation and resolving the false humidity warning.
Oak Park, IL 60302
Returned to property to investigate reported water leak in HVAC system. Upon inspection of attic space, located flexible supply duct with intact insulation wrapping and adjacent PVC condensate drain line. Examined surrounding areas and discovered deteriorated paper-backed insulation material on attic floor showing significant moisture damage, discoloration, and breakdown. Material exhibited yellowing, flaking, and crumbling consistent with previous water exposure. Documented conditions with photographs showing affected insulation and HVAC ductwork configuration. No active water leak detected at time of inspection from condensate drain line or ductwork connections. Recommended monitoring system for future leaks and advised replacement of damaged attic insulation to restore proper thermal efficiency.
Returned to property to investigate reported water leak in HVAC system. Upon inspection of attic space, located flexible supply duct with intact insulation wrapping and adjacent PVC condensate drain line. Examined surrounding areas and discovered deteriorated paper-backed insulation material on attic floor showing significant moisture damage, discoloration, and breakdown. Material exhibited yellowing, flaking, and crumbling consistent with previous water exposure. Documented conditions with photographs showing affected insulation and HVAC ductwork configuration. No active water leak detected at time of inspection from condensate drain line or ductwork connections. Recommended monitoring system for future leaks and advised replacement of damaged attic insulation to restore proper thermal efficiency.
Adrian M.
Adrian M. Checked in
Returned to property to investigate reported water leak in HVAC system. Upon inspection of attic space, located flexible supply duct with intact insulation wrapping and adjacent PVC condensate drain line. Examined surrounding areas and discovered deteriorated paper-backed insulation material on attic floor showing significant moisture damage, discoloration, and breakdown. Material exhibited yellowing, flaking, and crumbling consistent with previous water exposure. Documented conditions with photographs showing affected insulation and HVAC ductwork configuration. No active water leak detected at time of inspection from condensate drain line or ductwork connections. Recommended monitoring system for future leaks and advised replacement of damaged attic insulation to restore proper thermal efficiency.
Oak Park, IL 60302
Responded to no hot water complaint on tanked water heater system. Upon arrival, observed blower motor cycling with 3-flash error code indicating thermal cutout (TCO) or pressure switch failure in open position. Diagnosed faulty pressure switch preventing proper ignition sequence. Replaced defective pressure switch assembly and verified proper venting and combustion air supply. Tested unit through multiple heating cycles to confirm reliable ignition, proper flame operation, and hot water delivery restored to normal function.
Responded to no hot water complaint on tanked water heater system. Upon arrival, observed blower motor cycling with 3-flash error code indicating thermal cutout (TCO) or pressure switch failure in open position. Diagnosed faulty pressure switch preventing proper ignition sequence. Replaced defective pressure switch assembly and verified proper venting and combustion air supply. Tested unit through multiple heating cycles to confirm reliable ignition, proper flame operation, and hot water delivery restored to normal function.
Izzy G.
Izzy G. Checked in
Responded to no hot water complaint on tanked water heater system. Upon arrival, observed blower motor cycling with 3-flash error code indicating thermal cutout (TCO) or pressure switch failure in open position. Diagnosed faulty pressure switch preventing proper ignition sequence. Replaced defective pressure switch assembly and verified proper venting and combustion air supply. Tested unit through multiple heating cycles to confirm reliable ignition, proper flame operation, and hot water delivery restored to normal function.
Oak Park, IL 60302
Completed warranty return visit to address thermostat programming and verify refrigerant charge on recently installed HVAC system. Accessed attic-mounted air handler and ductwork to perform system diagnostics. Updated thermostat settings to manufacturer specifications and confirmed proper communication between thermostat and equipment. Measured refrigerant pressures and temperatures at service ports, verifying charge levels are within acceptable range for optimal system performance. Inspected ductwork connections and insulation integrity in confined attic space. System operating as designed with no deficiencies noted.
Completed warranty return visit to address thermostat programming and verify refrigerant charge on recently installed HVAC system. Accessed attic-mounted air handler and ductwork to perform system diagnostics. Updated thermostat settings to manufacturer specifications and confirmed proper communication between thermostat and equipment. Measured refrigerant pressures and temperatures at service ports, verifying charge levels are within acceptable range for optimal system performance. Inspected ductwork connections and insulation integrity in confined attic space. System operating as designed with no deficiencies noted.
Sean W.
Sean W. Checked in
Completed warranty return visit to address thermostat programming and verify refrigerant charge on recently installed HVAC system. Accessed attic-mounted air handler and ductwork to perform system diagnostics. Updated thermostat settings to manufacturer specifications and confirmed proper communication between thermostat and equipment. Measured refrigerant pressures and temperatures at service ports, verifying charge levels are within acceptable range for optimal system performance. Inspected ductwork connections and insulation integrity in confined attic space. System operating as designed with no deficiencies noted.
Oak Park, IL 60302
# HVAC System Replacement

Completed full HVAC system replacement including heat pump outdoor unit, air handler, and digital thermostat. New air handler was installed in attic space, properly suspended from structural beams with secure mounting hardware. Unit was connected with appropriate PVC condensate drainage and metallic flex ductwork. Digital programmable thermostat was mounted and configured, displaying system fault code 13-53 indicating control upgrade requirement that will need to be addressed during follow-up service visit.
# HVAC System Replacement

Completed full HVAC system replacement including heat pump outdoor unit, air handler, and digital thermostat. New air handler was installed in attic space, properly suspended from structural beams with secure mounting hardware. Unit was connected with appropriate PVC condensate drainage and metallic flex ductwork. Digital programmable thermostat was mounted and configured, displaying system fault code 13-53 indicating control upgrade requirement that will need to be addressed during follow-up service visit.
Anthony H.
Anthony H. Checked in
# HVAC System Replacement Completed full HVAC system replacement including heat pump outdoor unit, air handler, and digital thermostat. New air handler was installed in attic space, properly suspended from structural beams with secure mounting hardware. Unit was connected with appropriate PVC condensate drainage and metallic flex ductwork. Digital programmable thermostat was mounted and configured, displaying system fault code 13-53 indicating control upgrade requirement that will need to be addressed during follow-up service visit.
Oak Park, IL 60302
Completed HVAC maintenance agreement service call with arrival notification thirty minutes prior due to sleeping toddler in home. Performed comprehensive system inspection revealing significant condensate drainage issues with standing water in mechanical room and visible algae growth in drain pan. Documented internal equipment conditions including circuit board connections, wiring harness integrity, and condensate management components. System components photographed for maintenance records showing water intrusion requiring immediate attention to prevent further damage and maintain proper system operation.
Completed HVAC maintenance agreement service call with arrival notification thirty minutes prior due to sleeping toddler in home. Performed comprehensive system inspection revealing significant condensate drainage issues with standing water in mechanical room and visible algae growth in drain pan. Documented internal equipment conditions including circuit board connections, wiring harness integrity, and condensate management components. System components photographed for maintenance records showing water intrusion requiring immediate attention to prevent further damage and maintain proper system operation.
Joe A.
Joe A. Checked in
Completed HVAC maintenance agreement service call with arrival notification thirty minutes prior due to sleeping toddler in home. Performed comprehensive system inspection revealing significant condensate drainage issues with standing water in mechanical room and visible algae growth in drain pan. Documented internal equipment conditions including circuit board connections, wiring harness integrity, and condensate management components. System components photographed for maintenance records showing water intrusion requiring immediate attention to prevent further damage and maintain proper system operation.
Oak Park, IL 60302
Provided comprehensive estimate for complete air conditioning system replacement of twenty-year-old unit. Evaluated existing outdoor condenser unit showing significant age-related wear and assessed attic-mounted air handler with associated ductwork system. Documented current system configuration including exterior condenser placement on concrete pad adjacent to building structure and interior HVAC components installed in attic space with flexible metallic ductwork distribution network.
Provided comprehensive estimate for complete air conditioning system replacement of twenty-year-old unit. Evaluated existing outdoor condenser unit showing significant age-related wear and assessed attic-mounted air handler with associated ductwork system. Documented current system configuration including exterior condenser placement on concrete pad adjacent to building structure and interior HVAC components installed in attic space with flexible metallic ductwork distribution network.
Tyler B.
Tyler B. Checked in
Provided comprehensive estimate for complete air conditioning system replacement of twenty-year-old unit. Evaluated existing outdoor condenser unit showing significant age-related wear and assessed attic-mounted air handler with associated ductwork system. Documented current system configuration including exterior condenser placement on concrete pad adjacent to building structure and interior HVAC components installed in attic space with flexible metallic ductwork distribution network.
Oak Park, IL 60302

Client Testimonials

Read the opinions of our satisfied customers.

5 stars

This was my first time as a Deljo customer, and I was very pleased. My technician, Giovanni, was very thorough and diligent. He serviced my furnace and identified a faulty sensor that was causing the unit to shut itself down. Deljo ordered the part, and Giovanni replaced it a few days later. Overall, the team at Deljo was great. The dispatcher kept me informed about Giovanni’s arrival time, and the supervisor assisted Giovanni when he was diagnosing the problem with the furnace. I highly recommend Deljo.

Paul D. 10/15/2026

5 stars

I’ve used Deljo for over 10 years now and they always do a good job. Izzy was the technician for this visit and he did an excellent job with my winter maintenance on my multiple units in the household. He also addressed an issue while cleaning the furnace blower wheel. His communication was clear and concise with what he planned to do to address the issue quickly. He was confident and I had 0 concerns or questions. Great job Izzy!

Jeff S. 10/14/2026

5 stars

Paul was great! Arrived on time and completed maintenance on my humidifier, tankless water heater, and two furnaces. All work was performed under my Gold Star maintenance program, so all maintenance charges were covered. Paul did provide a few proposals for additional services on furnace & tankless water heater, but those were emailed to me for further consideration. Paul was friendly, knowledgeable, and answered all my questions.

Jack N. 10/12/2026

5 stars

Gabe did an excellent job with our annual service visit. He arrived in the early part of our service window, was friendly and knowledgeable, and got the work done in a very reasonable amount of time. I have great confidence in Deljo, and am a long-time customer.

Ruth C. 10/9/2026

5 stars

I’ve been using Deljo for 20 years for HVAC but now venture into enlisting their plumbing services. Bashar was very courteous, efficient & informative, and I’d definitely request him again for the next plumbing job. Great experience!

Christopher R. 10/2/2026

5 stars

Working with Deljo is always a good experience, and today’s appointment with Izzy was no different. He was able to come early which actually worked better with our schedules, but called me ahead of time to make sure that was okay. He was friendly and knowledgeable when he explained the work he had done during his visit and our options for fixes. He was also able to schedule a quote appointment for us while he was still here. We would highly recommend working with Izzy and the Deljo team!

Lauren H.  9/25/2026

5 stars

Drew performed the seasonal maintenance on my AC. It needed some repairs and updates and he was able to fix everything at the same appointment. He also noticed issues with the hot water heater and we were able to get ahead of that, as well.

Emily W. 9/11/2026

5 stars

I would leave six out of five stars if I could! My technician Jorge went above and beyond on his service. There was buildup in the rental property’s toilet from the previous tenant. One maintenance person did a surface level job of cleaning but did not fully remove the obstruction. Jorge went above and beyond and came to a solution and even explained the perpetual problems older toilet models can cause. Moving forward with this insight, I can perform my own upkeep the previous tenant did not. Thank you kindly!

Kayla K.  9/15/2026

5 stars

We just had our new boiler installed by Jonathan and Carlos. First rate work! They arrived on time, removed the old boiler, installed the new unit, and explained the features. Both guys were pleasant. Bring on the cold this winter! We are ready thanks to the team from Deljo.

Edward B.  6/26/2026

5 stars

Deljo’s heating and cooling team was awesome to work with. As a first-time homeowner, I really appreciated how clearly they explained everything and answered all my questions. From the quote to the install and follow-up, the service was top-notch. Highly recommend!

Lindsey A. Chicago, IL

5 stars

Matt did an amazing job. He serviced our home and our rental property. He gave us options to help our systems run more efficiently. He also told us about Deljo’s new plumbing inspection which was very affordable. He is great!

Jordan R. Chicago, IL

5 stars

We had a problem with our Humidifier and called Deljo. Jesus came out to help and was amazing. He was extremely knowledgeable, detail oriented, and super courteous. Amazing customer experience!

Jeff C. Chicago, IL

5 stars

Jordan and Jesus were extremely helpful and knowledgeable! We would 100% work with them and have them back. They were both very professional and efficiently fixed our heating system.

Emily L. Chicago, IL

5 stars

Shout out to Ernesto for coming out and servicing our furnace and air con. Deljo provides a great service and glad to trust them with our HVAC for our small business.

Lauren H. Chicago, IL

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