For over 90 years, the team at Thielmann has provided customers in Waukesha, Wisconsin with reliable, top-notch HVAC repair services. From heating and cooling to air quality and installation, we do it all so you can rest assured your home will be in its best condition and your family will be comfortable.
We also know life gets busy—that’s why we offer easy, convenient scheduling. Give our technicians a call at (262) 315-3067 or fill out our online form and someone will get back to you quickly.
Our Professionals Will Keep Your House Comfortable During the Fall, Winter, Spring, and Summer Seasons
The average temperatures in Waukesha, Wisconsin are radically different from winter to summer. Winters are known for being freezing, with some of the coldest months having temperatures in the low 20s. In contrast, the summers are humid, warm, and muggy.
Summer temperatures in Waukesha hit around 75°F but can get up to 90°F. The humidity from the surrounding lakes and rivers makes it feel hotter in the local area. Stay cool in this summer heat, and cozy and warm in the winter, when you work with our team of NATE-certified technicians. We will keep your house habitable throughout each season by helping you maintain your furnace, heat pump, boiler, or central air conditioner.
Air Conditioner Replacement and Installation Services
Sometimes, your air conditioner is on its last leg and the best move is not to repair it but to replace it completely. If this is the case our team of certified technicians is ready to help. With decades of experience in AC installation and replacement, we can handle putting in a new AC unit for you from start to finish.
We also provide heating and cooling services in Waukesha, Wisconsin for the best brands on the market and have flexible, easy financing options so you can stay within your budget.
Air Conditioning Repair Services
Summers in Wisconsin can get muggy and hot. Make sure your home is up for the task of keeping you cool by scheduling air conditioning repair or air conditioning tune-up services.
The best way to ensure your system is ready for summer is by having a technician come over and assess the condition of your air conditioner to confirm if it requires repairs.
Here are some of the components of an AC system we will check to see if it needs repair:
- Evaporator coil
- Compressor
- Condenser coil
- Expansion valve
- Filter
- Fan
We also offer air conditioner installation services for old systems that cannot be fixed. If you notice any weird noises, strange smells, or a lack of cold air, chances are you will need a repair or replacement.
Ductless Mini-Split Services
Homeowners in Wisconsin love ductless mini-splits because they are great for the ever-changing weather, from the frigid winters to the humid, muggy summers. Ductless mini-splits are super versatile and offer both heating and cooling options.
We offer the following mini-split services:
- Installation
- Replacement
- Repair
- Maintenance
- Inspections
Our team offers superior HVAC repair services and is fully equipped to handle any ductless mini-split issues, like refrigerant leaks, compressor problems, drainage malfunctions, frozen coils, electrical problems, blower issues, weird noises, and more.
Furnace Repair and Tune-Up Services
Keep your home warm and cozy for the winter with our reliable furnace repair and tune-up services for local residents in Waukesha, Wisconsin.
We can work on any system you have, like:
- Gas furnaces
- Oil furnaces
- Heat pumps
- Packaged units
- Boilers
Furnace Installation and Replacement Services
We can install gas, oil, or electric systems for your convenience. Whether your old system is on the fritz and you need a furnace replacement, or you have a brand-new property and need a furnace installed, we will take care of it.
Heat Pump System Installation Services
Wisconsin residents also use heat pumps to stay warm in the cold winters. Our NATE-certified technicians specialize providing extensive heating and cooling services in Waukesha and will keep you updated from start to finish on the project.
To receive support with a heat pump installation or heat pump repair, contact or HVAC contractors to receive support. Our technicians have the training necessary to fix your broken heat pump system.
Boiler Installation and Repair Services
Another popular heating system, boilers are a great energy-efficient way to heat your home. We offer HVAC installation, repair, maintenance, and tune-ups on boilers.
If you notice any of the following signs, contact us for boiler repair:
- Insufficient heat
- Foul odors
- Strange noises
- Cold air
- Yellow pilot light
We also offer routine boiler maintenance to expand the longevity of your system and ensure it is fully functional when you need it.
Thermostat Installation, Replacement, and Repair Services
Your thermostat is the remote control for your climate comfort. It controls heating and cooling functions but is often one of the most overlooked components of your HVAC system.
If you begin noticing malfunctions in your HVAC system, before rushing to assumptions that a motor is broken or you need a full replacement, consider your thermostat. We offer thermostat installation, replacement, and repair services.
Commercial Heating Maintenance and Replacement Services
Just like homes, businesses and commercial spaces need to offer a good climate-controlled environment to keep patrons and employees alike comfortable.
If you notice anything off about your business’s HVAC system, call the professionals at Theilmann to receive fast and convenient commercial heating repairs and services. Our 90 years of expertise means we’ve seen it all, not just in residential spaces but in commercial ones as well.
Professional Plumbing Services in Waukesha WI
Thielmann Heating, Cooling, and Plumbing has been serving Waukesha homeowners for over 90 years. Our licensed plumbers handle every type of plumbing issue with precision and care. From minor leaks to full system replacements, we provide clear solutions that keep your home running smoothly.
A plumbing issue can quickly disrupt your day. That’s why we respond quickly and get the job done right the first time. Our technicians inspect your system, identify the problem, and provide straightforward options that fit your needs and budget. We use trusted materials and proven methods to ensure repairs last.
We offer a full range of plumbing services in Waukesha:
- Drain & Sewer Cleaning: Clear out blockages and buildup to restore smooth water flow and prevent future clogs.
- Fixture Repair & Installation: Replace or repair faucets, toilets, and sinks for improved performance and reduced water waste.
- Water Heater Repair & Replacement: Maintain, repair, or upgrade tank and tankless models for steady hot water and better efficiency.
- Water Treatment & Filtration: Remove hard minerals and impurities for cleaner, healthier water throughout your home.
- Water Line Repair & Replacement: Fix damaged pipes or install new water lines to maintain consistent pressure and prevent leaks.
- Sump Pump Repair & Installation: Keep your basement safe from flooding with expert sump pump maintenance and installation.
Homeowners throughout Waukesha trust Thielmann Heating, Cooling, and Plumbing for honest work and dependable service. We take pride in our craftsmanship and commitment to customer satisfaction. When you need professional plumbing you can trust, call Thielmann today and let our experts take care of your home.
Take Back Your Weekends and Worry Less About Cooling and Heating Repairs in Your House
One of the advantages of working with our team of professionals includes having more time to enjoy your free time in Waukesha. While we take care of solving your HVAC problems, you can spend your time out on the town.
Take a stroll around Sanctuary Woods or visit the Waukesha County Historical Society and Museum. Our technicians will quickly inspect and fix your malfunctioning furnace or air conditioner to ensure you have time to enjoy your weekend.
Book a Heating or Cooling Appointment With Our Team in Waukesha
Our team in Waukesha is available any day for heating and cooling services. From boiler repair and heat pump installation to AC maintenance plans and heaters repairs, we have you covered. We also are skilled in air quality and offer duct cleaning, whole-home humidifiers, and other air purification services.
Simply fill out our form online or give us a call at (262) 315-3067 to receive assistance.
Recent Jobs and Reviews in Waukesha, WI
Waukesha, WI at a glance
Thielmann Heating, Cooling & Plumbing has completed 20 jobs in Waukesha, WI in October 2026.
The most recent job was on October 13, 2026.
Thielmann Heating, Cooling & Plumbing has completed 247 jobs in Waukesha, WI in the last 12 months.
Job Locations and Reviews
Performed an on-site estimate for proactive replacement of an aging, fully operational gas furnace and air conditioning system located in the basement, currently a 70,000 BTU furnace paired with a 14 SEER AC. Evaluated the existing equipment and associated components, including supply register and duct boot configuration, Aprilaire digital controller, and ventilation fan control, to determine replacement scope and system compatibility.
Conducted estimate for replacement of 28+ year old natural gas furnace and air conditioning system located in basement area of tri-level residence. Existing olive-green cabinet-style furnace unit with metal ductwork connections showed age-related wear consistent with equipment at end of service life. Documented current HVAC equipment configuration, ductwork layout, and installation access points for replacement planning. Photographed existing furnace installation, water heater proximity, basement utility room conditions, and floor drain location to assess equipment removal and new system installation requirements.
Completed routine heating system tune-up and safety inspection as part of recurring family membership maintenance visit. Performed comprehensive evaluation of furnace components including blower motor assembly, gas valve operation, electrical connections, control board functionality, and heat exchanger integrity. All systems tested and found operating within manufacturer specifications with no immediate service needs identified.
Completed warranty replacement of failed inducer motor assembly on residential furnace system. Removed defective motor, installed new OEM replacement unit, verified proper electrical connections and secure mounting, and confirmed system operation with successful startup and diagnostic check.
Completed furnace and air conditioning tune-up maintenance on residential HVAC system. Performed system diagnostics using manifold gauges to verify refrigerant pressures and electrical testing to confirm proper amperage draw on outdoor condensing unit. All equipment operating within manufacturer specifications.
Responded to no heat call on furnace installed earlier this year. Upon inspection, found burner assembly with flame sensor requiring attention. Performed thorough cleaning of flame sensor rod using appropriate brush tool to remove carbon buildup and oxidation. Verified all electrical connections to burner assembly and control board were secure. Tested ignition sequence and confirmed proper flame detection. System restored to full heating operation with all safety controls functioning as designed.
Completed routine membership heating maintenance visit on residential gas furnace. Performed comprehensive system inspection including visual examination of heat exchanger assembly, gas valve controls, electrical connections, draft inducer motor, and venting components. All internal components were accessed, inspected for proper operation, and verified to be in good working condition with no signs of damage or deterioration.
Conducted on-site evaluation for installation of second water heater to supplement existing unit experiencing rapid hot water depletion. Assessed current mechanical room configuration including existing water heater, water treatment systems, and available space for additional unit installation. Documented existing plumbing connections, electrical service capacity, venting requirements, and necessary modifications to accommodate dual water heater system.
Completed estimate for replacement of existing York natural gas furnace and air conditioning system located in basement mechanical room. Both units currently operational but aging, with customer seeking proactive replacement to avoid emergency failure situation. Assessed existing equipment configuration, ductwork connections, electrical wiring at thermostat, condensate drainage, and refrigerant line routing to provide comprehensive replacement proposal.
Completed installation of utility sink with full plumbing connections. Installed hot and cold water supply lines and connected drain line to existing plumbing system. Sink was properly leveled, secured, and tested for proper operation and leak-free connections.
Completed comprehensive furnace and air conditioning tune-up service at residential property. Inspected outdoor condenser unit, finding significant accumulation of grass clippings, leaves, and organic debris around capacitor and electrical components that required removal to prevent airflow restriction and potential component failure. Cleaned condenser coil fins, verified capacitor function and electrical connections, and ensured all wiring terminals were secure and free from corrosion.
Successfully removed and disconnected the existing water softener system, including all associated supply and drain piping. Replaced the second-floor bathtub drain assembly and waste/overflow system, ensuring proper fit and seal. All copper piping was reconfigured as needed, connections were secured with appropriate fittings, and the system was tested for proper drainage and functionality.
Conducted comprehensive assessment of residential HVAC system and water heater for replacement estimate. Evaluated existing furnace unit with metal ductwork, air conditioning system, and standard residential water heater with venting configuration in basement utility area. Documented current equipment specifications, installation conditions, and photographed existing setup including water heater with copper piping connections, flexible vent ductwork, furnace with condensate drain line to floor drain, and overall system layout for replacement proposal preparation.
Responded to service call for outdoor condenser unit producing excessive rattling noise. Upon arrival, inspected Lennox air conditioning condenser unit and identified source of noise disturbance. Performed necessary repairs to eliminate rattling condition and restored unit to normal quiet operation.
Completed comprehensive furnace tune-up on Carrier brand heating unit. Performed full system inspection including internal mechanical components, electrical connections, motor assembly, and control systems. Verified proper operation of all safety controls, cleaned burner assembly, checked gas connections, and confirmed all wiring harnesses and color-coded electrical connections were secure and functioning correctly.
Completed preventative maintenance tune-up on HVAC system. Inspected blower motor assembly, electrical connections, capacitor, and wiring harness; verified all components operating within normal parameters. Documented equipment condition with interior component photography showing motor housing, ductwork connections, and electrical system intact with no immediate service needs identified.
Responded to no hot water condition and performed on-site assessment of existing water heater system. Documented measurements and current equipment specifications, including tank dimensions and venting configuration. Evaluated deteriorated vent pipe showing significant galvanized coating failure and corrosion. Captured photographic documentation of existing water heater unit and compromised venting components for estimate preparation. Prepared comprehensive replacement estimate and coordinated follow-up communication to review proposed scope of work for water heater and venting system replacement.
Installed battery backup system for existing sump pump assembly in basement utility area. Completed installation with proper electrical connections and PVC piping integration to ensure continuous operation during power outages.
Completed full furnace replacement including installation of new Lennox unit with zoning system upgrades. Installed new zone control panel, zone sensor, three motorized dampers, and AA 600 humidifier to optimize multi-zone climate control. Modified venting system with 3-inch PVC exhaust piping and adapted ductwork connections to existing filter cabinet. Coordinated with licensed electrician for electrical connections and obtained required permit for installation. System tested and verified operational with all zones responding properly to control inputs.
Performed no-charge second opinion inspection and equipment assessment of residential furnace system. Documented existing Carrier humidifier installation, ductwork configuration, and associated electrical connections. Collected equipment information and specifications including model numbers and system components for customer records.
