For more than a century, Deljo Heating & Cooling has been the name Evanston homeowners trust for reliable comfort solutions. Whether you need HVAC or plumbing solutions, our team delivers expert care backed by 5-star reviews and over 100 years of experience.
If you’re experiencing an HVAC or plumbing emergency, call us or click the button at the top of the page to schedule service online. Keep reading for an overview of our Evanston HVAC and plumbing services.
Plumbing Services in Evanston
No matter the issue, you can trust Deljo for prompt, affordable, and professional plumbing services. Our team provides comprehensive plumbing repair, from small leaks to major system issues.
If your hot water suddenly runs cold, we specialize in water heater repair, restoring comfort with fast and professional service. For clogged or slow drains, our expert drain cleaning clears buildup and keeps your plumbing flowing smoothly.
Air Conditioning Services in Evanston
Summers in Evanston demand a dependable cooling system. That’s why Deljo offers expert air conditioner repair to restore your comfort quickly when your AC breaks down. From refrigerant issues to electrical malfunctions, our licensed technicians handle every kind of AC issue. We also provide seasonal air conditioning maintenance and professional air conditioning installation to keep your home comfortable all summer long.
Heating Services in Evanston
When temperatures drop, Deljo is here to keep your family warm with expert heating services. If your furnace stops working or struggles to heat evenly, call us for reliable furnace repair. Our technicians provide thorough diagnostics and long-lasting repairs so you’re never left in the cold.
We also specialize in boiler repair and professional heating installation, ensuring your system runs safely and efficiently for years to come.
Why Choose Deljo Heating & Cooling in Evanston?
There are plenty of companies you could call when something goes wrong with your plumbing or HVAC. But Evanston families have been turning to Deljo for generations. The reasons why they do this include:
- We show up when it matters most. Burst pipes and broken furnaces don’t wait for a convenient time. That’s why we’re available 24/7 for emergency HVAC and plumbing services.
- We’ve been doing this for over 100 years. Over our century of operation, we’ve seen it all. We know how to get the job done right the first time.
- Our reputation speaks for itself. We’re proud of the thousands of 5-star reviews we’ve earned. They don’t come from flashy ads. They come from neighbors who were treated fairly and had their problems solved quickly.
- We make comfort affordable. Big repairs and replacements can be stressful. That’s why we offer flexible financing options that take the sting out of an unexpected bill.
- We take care of our customers. With our Gold Star Program, customers get priority scheduling, regular maintenance, and extra perks. It’s our way of saying thank you for trusting us with your home.
At Deljo, it’s simple: we treat you the way we’d want to be treated. That’s been our approach for more than a century, and it’s why so many Evanston families keep our number handy.
Call Your Trusted Evanston Plumbing & HVAC Experts
Ready to take care of that plumbing issue or finally get your heating and cooling running the way it should? Deljo Heating & Cooling is here to help. Give us a call or request an instant quote today and see why Evanston has trusted us for over 100 years.
Recent Jobs and Reviews in Evanston, IL
Evanston, IL at a glance
Deljo Heating, Cooling & Plumbing has completed 20 jobs in Evanston, IL in August 2026.
The most recent job was on August 20, 2026.
Job Locations and Reviews
Replaced defective ecobee thermostat under manufacturer warranty and verified system airflow settings for continuous fan operation. Reviewed equipment upgrade options with homeowner, discussing available HVAC system replacements and efficiency improvements.
Completed scheduled HVAC maintenance agreement inspection on residential condensing unit and furnace system. Performed comprehensive visual inspection of outdoor condenser unit, examining electrical components including capacitor, contactor, and associated wiring connections for proper operation and signs of wear. Inspected indoor furnace unit located in utility closet alongside water heater, verified ductwork connections and system accessibility. All equipment found operating within normal parameters, no immediate repairs required at this time.
Disconnected existing Honeywell HZ322 multi-zone HVAC control system and converted system to single-zone operation. Cut drywall to access zone dampers throughout ductwork and manually locked all dampers in the open position to allow unrestricted airflow. Removed zone control wiring from terminal blocks and bypassed zoning panel to restore direct thermostat control to HVAC unit. System tested and confirmed operational as single-zone configuration with proper airflow to all areas.
Conducted on-site evaluation of vintage first-floor condo unit to assess requirements for new cooling system installation. Inspected existing basement mechanical space, documenting current HVAC infrastructure including exposed ductwork, copper refrigerant lines, PVC condensate drainage, and electrical service panel accessibility. Evaluated ceiling joist configuration, available clearances for equipment placement, and existing utility connections to determine optimal system sizing and installation approach for split-system air conditioning unit.
Completed comprehensive air conditioning maintenance agreement service on residential cooling system. Performed thorough inspection of outdoor condenser unit, verified electrical connections and refrigerant levels, cleaned and evaluated indoor air handler components in mechanical space. Customer declined 16x25x4 air filter replacement at this time; unit operational and system passed all diagnostic checks.
Responded to service call regarding main floor thermostat not maintaining temperature. Performed diagnostic inspection of HVAC system in attic space, including temperature measurements of supply ductwork which registered 53.8°F at the plenum. Inspected duct board construction, insulation integrity, and system components to identify cause of inadequate heating performance. Contacted homeowner via phone and text message with findings and diagnosis as requested.
Completed scheduled HVAC maintenance agreement service on cooling system. Performed inspection of air handler unit, verified proper operation of electrical components including capacitor and relay, checked wiring connections, and inspected return air filter grate. All components found operating within normal parameters and system functioning properly.
Completed spring cooling tune-up on residential air conditioning system. Performed comprehensive inspection of condenser unit, verified thermostat operation showing 74°F set point in hold mode, and documented severe frost accumulation on evaporator coil with surface temperature reading of 62.6°F. The extensive ice buildup on the coil indicates potential airflow restriction, refrigerant charge issue, or system operating continuously below design parameters that will require further diagnosis and correction to restore proper cooling performance.
Completed general service maintenance on three air conditioning units and one fan coil unit. Performed system inspections, replaced air filters including installation of new MERV 11 rated filter, and verified proper operation of control boards and electrical connections on all equipment.
# Plumbing Inspection - Pipe Leak Investigation Near Boiler Conducted comprehensive plumbing inspection with primary focus on reported pipe leak in vicinity of boiler system. Inspection revealed the leak originated from piping independent of the boiler unit itself, located in the mechanical room area. ## Work Performed Performed thorough examination of all accessible plumbing systems throughout the property. Inspected basement mechanical room housing water heater, boiler unit, and associated piping infrastructure. Evaluated condition of copper supply lines, PVC drainage systems, and sump pump installation. Identified leak source at pipe connection near but not integrated with the teal-colored boiler unit. Verified the compromised pipe was part of the general plumbing system rather than boiler-specific components. Assessed surrounding copper piping, insulated lines, and multiple valve assemblies for additional concerns. Examined sump pump basin with multiple white PVC discharge pip
Completed comprehensive cooling maintenance on three air conditioning systems and three Unico small-duct high-velocity blowers as part of routine maintenance agreement. Replaced air filters throughout the property using specified sizes: 16x25x1, 14x20x1, and 12x30x1 filters for the guest suite second floor unit. Inspected evaporator coils and found normal condensation on metal ductwork assembly indicating proper system operation and temperature differential. Examined refrigerant lines, ductwork connections, and air handler components in confined installation spaces. All systems operating within normal parameters with no deficiencies noted.
Completed HVAC maintenance agreement inspection at residential property. Accessed property using lockbox, performed comprehensive system evaluation of heating and cooling equipment located in basement utility area, documented equipment conditions with photographs, and verified all mechanical systems operating within normal parameters.
Returned to system to add R-410A refrigerant with sealant, charging up to 3 pounds to address refrigerant loss. Connected manifold gauges to service ports on weathered copper refrigerant lines and performed leak detection procedures. Added leak sealant to system followed by refrigerant charge to restore proper operating pressures and system capacity.
Completed comprehensive HVAC maintenance agreement service including air conditioning system and water heater inspection. Verified air filter condition and accessibility, documented clean pleated filter media in return air housing, and inspected ductwork components and water heater combustion chamber opening with gasket seal intact and operational.
Completed comprehensive estimate for full HVAC system replacement of 20-year-old R22 unit. Assessed existing outdoor condenser unit located on elevated deck area and evaluated interior components including refrigerant line set configuration. Documented current system measurements and photographed installation site conditions to determine equipment specifications and access requirements for replacement.
Responded to emergency no cooling call on Carrier air handler system located in attic space. Upon arrival, connected manifold gauges to assess refrigerant pressures and system operation. Diagnosed system issue and performed necessary service to restore cooling function.
Relocated rooftop condenser unit with new refrigerant line routing across flat membrane roof surface. Secured copper refrigerant lines with metal straps and yellow plastic brackets, running insulated and bare copper piping between equipment locations. Electrical relocation work was not included in this scope of work.
Completed comprehensive HVAC maintenance agreement service including full system inspection of Carrier air handler unit and Bradford White water heater. Performed routine maintenance checks on both systems, verified proper operation of all components, replaced 16x20x1 air filter, and documented equipment conditions with photographic records for maintenance history files.
Provided remote quote for rooftop HVAC equipment replacement on commercial building. Assessed existing Lennox condenser units positioned on flat membrane roofing surface and documented current installation conditions including equipment placement, mounting pads, and rooftop access considerations for replacement work.
Completed preventative maintenance agreement service on multiple HVAC systems including three condensing units and replaced two Infinity air filter cartridges (AGAPXCAR1625). Performed standard maintenance procedures on outdoor condensing units, accessing internal electrical components and circuit boards for inspection. Utilized refrigerant gauge manifold and vacuum pump equipment to verify system pressures and refrigerant charge levels. Replaced indoor air filtration media at return air grilles to maintain proper airflow and system efficiency per maintenance agreement specifications.
