Your Trusted Home services Company Since 1975
A family-operated company based in Louisville, A+ Derr Heating & Cooling has proudly served the Louisville community for half a centruy. Our decades of experience have equipped us with the skills and tools necessary to solve all of your HVAC and plumbing needs. Our comprehensive heating and cooling services will bring you the solutions you need to stay at a comfortable temperature in your home year-round, and our expert plumbing services will ensure everything flows without disruption. For A+ service, choose A+ Derr! Contact us today to schedule heating, air conditioning, or plumbing services in Louisville.
Air Conditioning Services
Don’t let the summer heat turn your home into an oven! Our team is highly trained to address all of your AC needs, whether for routine maintenance, a complex repair, or a complete system replacement. You can count on our friendly technicians to ensure your home is cool even when the temperatures start to soar outside. Our air conditioning services in Louisville include:
Signs You Need AC Repair
The sooner you can schedule air conditioning repairs, the better. When left unaddressed, problems will only worsen and can cause damage to other parts of your AC unit. Quick action can prevent further issues, so call our team for AC repairs as soon as you notice any of the following signs:
- Lack of airflow/problems with startup
- Lack of cool air
- Leaks
- Loud noises
- Off-putting odors
- Unusually high utility bills
Heating Services
At A+ Derr, your comfort is our top priority, so we don’t want you to be freezing in your own home. If your furnace is on the fritz or you need a heat pump installed, our team has you covered! We’re even available 24/7 if your furnace goes out in the middle of the night. Our comprehensive heating services include:
Signs You Need Furnace Repair
Some signs that your furnace isn’t working as it should are obvious, such as a complete lack of heat. Others may not be, so here’s what to look out for:
- Insufficient heating
- Short-cycling (i.e., unit turning on and off quickly)
- Burning smells
- Loud noises, such as banging, whirring, buzzing, etc.
- Unexplained rise in energy bills
Indoor Air Quality Solutions in Louisville
A+ Derr wants to ensure you can breathe easily in your home, so we offer whole-home air quality solutions for your benefit. If you’ve noticed that you have worsening allergy or asthma symptoms, dry skin, itchiness, or are becoming ill more frequently, it’s time to take steps toward improving your air quality. Contact A+ Derr for the following air quality services in Louisville:
Plumbing Services
Plumbing problems can quickly disrupt your day and cause chaos in your home. Fortunately, A+ Derr is ready to help with your plumbing issues, no matter how big or small! Our highly trained and friendly plumbers provide a wide range of plumbing services in Louisville, including:
- Plumbing repair
- Plumbing installation
- Plumbing maintenance
- Water heater repair
- Water heater installation
- Tankless water heater service
- Sump pump installation
- Sump pump repair
- Drain cleaning
- And more
Louisville Customer Experiences
At A+ Derr, we put our values of professionalism, punctuality, quality, responsiveness, and value into everything we do. We believe in always providing the best customer experience, from our friendly technicians to our top-notch HVAC services. But don’t just take our word for it! Read these reviews from your fellow Louisville residents that show why working with us is an A+ experience:
- “Absolutely love A+ Derr! They were extremely professional from the start, and explain everything thoroughly. Always answers any questions that I have. Best part is they send you a picture of the tech that is coming to your house. I think that is amazing, so you know who is coming that way you know beforehand. Definitely a great safety measure. 100% satisfied with this company. Would recommend to anyone.”
- “Used this company to replace our HVAC system and for maintenance. They provide top notch service and equipment at a reasonable price! Technicians have all been friendly and answered all my questions. I recommend them to family, friends and clients in need of their services.”
- “I purchased my new energy efficient unit from A+ Derr over 3 years ago. They have always been professional, on time, and provide excellent quality service. They have always been straight forward with me from day one. I did my research before selecting A+ Derr, and very happy that I chose the right company the first time.”
Why Choose A+ Derr Heating & Cooling?
Since 1975, A+ Derr Heating & Cooling has provided the HVAC and plumbing solutions that Louisville families need to stay comfortable in their homes. As a fourth-generation, family-operated company, we always put the customer first. That’s why you can count on us to provide:
- 24/7 emergency service
- 100% satisfaction guarantee
- Free estimates on replacement quotes and service calls
- Highly trained and courteous technicians
Ready to work with our team of friendly experts? Reach out to us today to schedule HVAC or plumbing services in Louisville, KY.
Louisville HVAC & Plumbing FAQs
What indoor humidity level should I target during Ohio Valley summers?
Aim for 40 to 50 percent relative humidity for comfort and to help your AC work efficiently. If your home stays sticky even when the temperature is right, ask about airflow checks and whole-home dehumidification.
How can I prep for a same-day HVAC visit in Louisville?
Clear a path to the thermostat, air handler, electrical panel, and outdoor unit, replace a very dirty filter, and note noises, odors, or rooms that struggle. Easy access helps the technician diagnose quickly.
Do older Highlands or St. Matthews homes benefit from zoning?
Yes. Zoning uses dampers and separate thermostats so each level gets the airflow it needs. It helps upstairs bedrooms cool at night without over-cooling the main level.
Which SEER2 range makes sense for Louisville’s cooling season?
Mid to high SEER2 systems often deliver strong value when paired with correct sizing, sealed ducts, and a smart thermostat. Whole-home performance matters more than the rating alone.
What should I check before calling for AC repair on a hot afternoon?
Verify Cool mode with Auto fan, set the thermostat a few degrees below room temperature, make sure supply and return vents are open, and replace a clogged filter. If breakers trip or the outdoor fan hums without spinning, shut the system down and schedule service.
Will duct cleaning help with seasonal allergies in Louisville?
It can when paired with proper filtration and humidity control. A visual inspection, static-pressure test, and filter review will confirm if cleaning delivers a measurable benefit.
How do I keep the outdoor unit quiet for me and my neighbors?
Set the condenser on a level pad with clear side and top airflow, trim vegetation, and use vibration pads. Avoid locating the discharge near bedroom windows.
What is considered an HVAC emergency for Louisville homes?
No cooling or no heat during extreme weather, repeated breaker trips, smoke or burning smells, or water near equipment are urgent. Power the system off and request immediate service.
Can a heat pump work well in Louisville or should I stay with a furnace and AC?
Modern heat pumps cool efficiently and provide economical heat in spring and fall. Many homeowners choose a dual-fuel setup that uses the heat pump most of the year and the furnace during deeper cold.
What helps even out temperatures in long shotgun or two-story floor plans?
Check for open returns, correct blower speed, and balanced supplies. Adding return air to closed rooms, sealing leaky ducts, and considering zoning often solves hot-room complaints.
Recent Jobs and Reviews in Louisville, KY
Job Locations and Reviews
Completed monthly Platinum Level planned maintenance on a 2-year-old HVAC system. Performed comprehensive system inspection, recorded temperature readings showing 57.5°F and 56.88°F at measured points, and replaced monthly filters as part of recurring service agreement. All components operating within normal parameters.
Installed a 50-gallon AO Smith ProLine electric residential water heater in utility closet. Connected hot and cold water supply lines with proper color-coded flexible connectors and brass fittings, ensuring all plumbing connections were secure and leak-free per manufacturer specifications.
Responded to a free second opinion request for an air conditioning system that has not been keeping up with cooling demands. Accessed the crawl space to inspect the HVAC system installation and measured supply air temperature and airflow at floor registers using diagnostic equipment. Found the property had only received previous boiler service with no prior AC maintenance history, requiring a comprehensive system evaluation to determine why the cooling system was underperforming.
Conducted site assessment for furnace relocation project in unfinished basement area. Evaluated existing Goodman furnace unit and current ductwork configuration to provide estimate for relocating equipment and installing new duct system. Documented present conditions including exposed framing, concrete flooring, existing electrical routing, and accumulated debris in workspace. Assessed attic/crawl space areas with existing flexible ductwork and insulation to determine scope of modifications required for relocated furnace and new duct installation.
Conducted on-site evaluation for HVAC replacement in a multi-room facility with existing wall-mounted units showing signs of wall staining and age-related deterioration. Measured and assessed two separate room locations (rooms 202 and 203) to provide equipment replacement options, specifically evaluating feasibility for either PTAC unit replacement or multi-head mini-split system installation. Documented existing unit dimensions, electrical connections, and spatial constraints to develop comprehensive replacement proposal for the homeowner.
Completed professional installation of A.O. Smith residential water heater in basement utility area, including all necessary plumbing connections with copper piping and brass fittings integrated into existing overhead infrastructure. Unit was properly positioned, secured, vented through galvanized ductwork, and tested for optimal performance with SENSE monitoring system staged for installation.
Completed Platinum Level planned maintenance on a 7-month-old single-system HVAC unit. Performed comprehensive system diagnostics including electrical current measurements on the outdoor condenser unit using a clamp meter to verify proper amperage draw and component operation. Measured supply air temperature at 67.5°F to confirm adequate cooling performance and system efficiency. Inspected all electrical connections, refrigerant lines, and ductwork for proper installation and operation. System operating within manufacturer specifications with no deficiencies noted.
Conducted comprehensive HVAC system evaluation for complete replacement estimate on aging residential installation. Assessed exterior condensing unit showing significant weathering and rust deterioration on protective grille, documented electrical service connections and meter configuration, and evaluated existing thermostat wiring configuration on UWP12 control module with multi-stage capability. Photographed all equipment conditions and provided detailed replacement recommendations for new energy-efficient system.
Completed installation of new air conditioning system including evaporator coil and ductwork modifications in residential attic space. Installed reflective insulated ductwork with proper routing and connections, integrated new metallic supply ducts with appropriate elbow fittings for optimal airflow distribution, and ensured all components were properly secured and sealed. System was tested for proper operation and airflow efficiency upon completion.
# HVAC Maintenance Service Completed Performed comprehensive preventive maintenance on a two-year-old residential air conditioning system per customer's scheduled tune-up request. System was operating normally with no reported issues at time of service. Conducted complete electrical diagnostics using digital multimeter to verify proper voltage and amperage across system components. All electrical readings confirmed within manufacturer specifications. Measured supply air temperature at 50.9°F, indicating adequate cooling performance and proper refrigerant charge levels. Completed standard maintenance protocol including inspection of all major components, verification of operational parameters, and system performance assessment. All measurements and observations documented photographically for service records. System left in proper working order with all safety controls functioning as designed.
Responded to no cooling complaint on 10-year-old system with warm air and low airflow from vents. Upon inspection, diagnosed failed dual run capacitor showing visible corrosion and oxidation on terminals and wire connections. Replaced defective capacitor with new unit, verified proper electrical connections, and tested system operation. Unit restored to normal cooling operation with proper airflow.
Conducted comprehensive replacement estimate at rental property for existing member whose current HVAC system is non-operational. Performed detailed load calculations using EDS software, determining cooling load requirements of 25,983 BTU and heating load requirements of 33,687 BTU based on structure characteristics including duct loss, ceiling, glass, wall, infiltration, and floor factors. Documented existing electrical panel configuration showing circuit breaker arrangement and confirmed adequate electrical infrastructure for replacement equipment installation.
Responded to no cooling complaint on upstairs system in newer home. Upon inspection, discovered failed contactor and blown fuses in outdoor condensing unit preventing compressor operation. Replaced defective contactor relay and multiple fuses in fuse block assembly, restoring proper electrical function to compressor circuit. Changed neglected air filter in master bedroom return grille located approximately 12 feet high. Verified system operation with proper airflow, compressor engagement, and adequate cooling capacity. Unit now operating within normal parameters and maintaining setpoint temperature.
Responded to service call for leaking water heater of unknown age. Upon inspection, found A.O. Smith Proline water heater with active leak at base of unit, though unit was still operational and producing hot water. Assessed condition of tank, plumbing connections, and pressure relief valve assembly. Documented existing installation including copper supply lines, proper venting, and current insulation configuration around lower portion of tank. Provided customer with assessment findings and recommended replacement due to age-related tank deterioration and active leak condition.
Conducted site assessment for ductwork insulation estimate in confined mechanical space. Documented existing conditions including uninsulated refrigerant lines, HVAC ductwork, and structural deterioration with moisture damage and staining on interior surfaces requiring attention prior to insulation installation.
Completed annual Platinum Level maintenance on a 1-year-old HVAC system during the first scheduled visit. Performed comprehensive system inspection and diagnostics using professional-grade testing equipment. Replaced 16x25x5 air filter as part of routine maintenance protocol. Utilized Klein Tools digital measuring device to verify temperature differentials and system performance metrics across ductwork and components. Employed True RMS multimeter (DL489) to test electrical parameters including voltage, current, and system functionality to ensure optimal operation. All measurements recorded within manufacturer specifications. System operating efficiently with no deficiencies noted. Documented findings with photographic evidence for service records.
Completed inspection of vintage-style shower and tub installation on second floor, verifying proper mounting and functionality of ornate brass fixture assembly with cross-handle controls, curved spout, and flexible shower hose. Ran new water supply lines through wall cavity for washer and dryer hookup, routing plumbing from second floor location with appropriate drainage considerations. All installations tested for leaks and proper water pressure, with fixtures operating within normal parameters.
Responded to after-hours service call to investigate system malfunction. Upon arrival, found indoor unit flashing green indicator light. Reset condenser disconnect switch, which restored system operation. Observed liquid line freezing and measured insufficient temperature split of approximately 12°F across both heads, indicating potential refrigerant or airflow issue. After condenser ramped up to full operation, rechecked temperature readings and confirmed improved split of 23°F (79°F return to 56°F supply). Advised occupant to maintain bedroom door open position to improve air circulation between zones and ensure proper airflow to primary occupied space. System left operational with monitoring recommended.
Upon arrival, identified a hose bib mounted on exterior brick wall with minor leakage at wall penetration point and evidence of previous water intrusion. Assessed interior access point and determined repair would require cutting into basement ceiling drywall, which was outside scope of work. Secured hose bib fixture directly to brick wall using anchoring hardware and applied silicone sealant around entire perimeter of wall penetration to prevent water infiltration and seal against environmental elements.
# HVAC Maintenance Summary Completed annual Platinum Level maintenance on a 6-year-old single-system residential HVAC unit. Performed comprehensive electrical diagnostics using digital multimeter to verify proper voltage, amperage, and capacitor functionality. Measured supply air temperature at 42.5°F, confirming adequate cooling performance. Inspected all electrical components including contactors, relays, and wiring connections. Replaced 16x20x5 air filter and verified system operation within manufacturer specifications.
