Trusted AC Repair in the Greater Madison Area
Need AC repair now? Our certified HVAC technicians fix air conditioners fast across the Greater Madison Area, including Madison, Sun Prairie, and Fitchburg. We’re family owned since 1949 and available 24/7, with a 4.9 rating from 1,693 reviews. As a Carrier Distinguished Dealer and Nest Elite Pro, we bring proven expertise to every service call. Beat the first heat wave and avoid breakdowns with prompt, honest repairs. Call (608) 478-8991 or book online. Ask about $25 off AC repair.
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"Get started with a complimentary service estimate today for emergency air conditioning repair."
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Complimentary service estimate for air conditioning repair.
- complimentary estimate
Why Choose Us
What Our Customers Say
"A technician was at our house in less than 30 minutes and restored our A/C."
"They explained the issue and fixed it efficiently. AC has run perfectly since."
"He made a wiring fix and maintenance, clearly explained options. Very pleased."
Answers to Common Questions
View All FAQsWhy Is My Air Conditioner Running But Not Cooling Properly?
Your AC is running but not cooling when airflow or refrigerant flow is restricted. Common causes are a dirty air filter, incorrect thermostat settings, low refrigerant from a leak, dirty coils, a blocked outdoor unit, or a blower/compressor issue. Harker techs inspect filters, coils, refrigerant charge/leaks, electrical connections, blower, and condensate drain during a Clean & Check. Refrigerant should not need refilling; needing a “recharge” signals a leak that should be repaired.
Quick checks:
- Replace the filter every 1–3 months.
- Set thermostat to Cool and lower the setpoint.
- Clear debris 2–3 feet around the outdoor unit.
- Open supply and return vents.
Updated: 2025-12-26 00:00:00
Need help in Madison, WI? Call (608) 313-5510 or book online.
[0] https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChdDSUhNMG9nS0VJQ0FnSURyZ0pXYXlBRRAB!2m1!1s0x0:0xf55f104e093c221f!3m1!1s2@1:CIHM0ogKEICAgIDrgJWayAE%7CCgsI8erFtAYQuJCCDg%7C?hl=en-US[1] https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sCi9DQUlRQUNvZENodHljRjlvT21SNE5YbHBTRkZVTUROVmIzcHZWbEEwV1dOYVFsRRAB!2m1!1s0x0:0xf55f104e093c221f!3m1!1s2@1:CAIQACodChtycF9oOmR4NXlpSFFUMDNVb3pvVlA0WWNaQlE%7C0cJoHhGpnz5%7C[2] https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChZDSUhNMG9nS0VJQ0FnSURicUlpd1N3EAE!2m1!1s0x0:0xf55f104e093c221f!3m1!1s2@1:CIHM0ogKEICAgIDbqIiwSw%7CCgwI1L2utQYQkK_3tAM%7C?hl=en-US[3] https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChZDSUhNMG9nS0VJQ0FnSUNidEtHT0VnEAE!2m1!1s0x0:0xf55f104e093c221f!3m1!1s2@1:CIHM0ogKEICAgICbtKGOEg%7CCgwIkcGAtQYQuMvSxQM%7C?hl=en-US[4] https://www.harkerheating.com/contact/[5] https://www.harkerheating.com/support/financing/energy-federal-tax-credits/[6] https://www.harkerheating.com/our-services/heating/[7] https://www.harkerheating.com/our-services/cooling/specialty-units/Why Is My AC Running But Not Cooling Properly?
Your AC can run but not cool due to a clogged air filter, dirty outdoor coils, incorrect thermostat settings, or a refrigerant leak. Low refrigerant usually means a leak that should be repaired, not refilled. Blocked drains, failing blower parts, or loose electrical connections can also reduce cooling. Our technicians check filters, coils, refrigerant charge, safeties, blower assembly, and condensate drains during service. We offer 24/7 emergency HVAC service across Madison and nearby cities.
Quick checks:
- Replace the air filter every 1–3 months.
- Clear debris and gently rinse outdoor coils.
- Confirm thermostat is set to Cool and the temperature is lower than room temp.
Updated: 2025-12-26
Need help in Madison, WI? Call (608) 313-5510 or book online.
[0] https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChdDSUhNMG9nS0VJQ0FnSURyZ0pXYXlBRRAB!2m1!1s0x0:0xf55f104e093c221f!3m1!1s2@1:CIHM0ogKEICAgIDrgJWayAE%7CCgsI8erFtAYQuJCCDg%7C?hl=en-US[1] https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sCi9DQUlRQUNvZENodHljRjlvT21SNE5YbHBTRkZVTUROVmIzcHZWbEEwV1dOYVFsRRAB!2m1!1s0x0:0xf55f104e093c221f!3m1!1s2@1:CAIQACodChtycF9oOmR4NXlpSFFUMDNVb3pvVlA0WWNaQlE%7C0cJoHhGpnz5%7C[2] https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChZDSUhNMG9nS0VJQ0FnSURicUlpd1N3EAE!2m1!1s0x0:0xf55f104e093c221f!3m1!1s2@1:CIHM0ogKEICAgIDbqIiwSw%7CCgwI1L2utQYQkK_3tAM%7C?hl=en-US[3] https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChZDSUhNMG9nS0VJQ0FnSUNidEtHT0VnEAE!2m1!1s0x0:0xf55f104e093c221f!3m1!1s2@1:CIHM0ogKEICAgICbtKGOEg%7CCgwIkcGAtQYQuMvSxQM%7C?hl=en-US[4] https://www.harkerheating.com/contact/[5] https://www.harkerheating.com/support/financing/energy-federal-tax-credits/[6] https://www.harkerheating.com/our-services/heating/[7] https://www.harkerheating.com/our-services/cooling/specialty-units/What should I do if my AC is blowing warm air intermittently?
If your AC blows warm air on and off, start with quick checks, then schedule a diagnostic. Set the thermostat to Cool and lower it a few degrees. Replace the air filter. Clear debris around the outdoor unit and gently rinse the coils. Make sure the breaker is on and the condensate drain isn’t clogged. Intermittent warm air often needs a pro to check refrigerant charge, electrical connections, capacitors/contactors, and coil cleanliness per our Clean & Check.
We serve Madison and Sun Prairie with 24/7 emergency help.
Updated: 2025-12-26
Need help in Cross Plains, WI? Call (608) 313-5510 or book online.
[0] https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChdDSUhNMG9nS0VJQ0FnSURyZ0pXYXlBRRAB!2m1!1s0x0:0xf55f104e093c221f!3m1!1s2@1:CIHM0ogKEICAgIDrgJWayAE%7CCgsI8erFtAYQuJCCDg%7C?hl=en-US[1] https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sCi9DQUlRQUNvZENodHljRjlvT21SNE5YbHBTRkZVTUROVmIzcHZWbEEwV1dOYVFsRRAB!2m1!1s0x0:0xf55f104e093c221f!3m1!1s2@1:CAIQACodChtycF9oOmR4NXlpSFFUMDNVb3pvVlA0WWNaQlE%7C0cJoHhGpnz5%7C[2] https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChZDSUhNMG9nS0VJQ0FnSURicUlpd1N3EAE!2m1!1s0x0:0xf55f104e093c221f!3m1!1s2@1:CIHM0ogKEICAgIDbqIiwSw%7CCgwI1L2utQYQkK_3tAM%7C?hl=en-US[3] https://www.google.com/maps/reviews/data=!4m8!14m7!1m6!2m5!1sChZDSUhNMG9nS0VJQ0FnSUNidEtHT0VnEAE!2m1!1s0x0:0xf55f104e093c221f!3m1!1s2@1:CIHM0ogKEICAgICbtKGOEg%7CCgwIkcGAtQYQuMvSxQM%7C?hl=en-US[4] https://www.harkerheating.com/contact/[5] https://www.harkerheating.com/support/financing/energy-federal-tax-credits/[6] https://www.harkerheating.com/our-services/heating/[7] https://www.harkerheating.com/our-services/cooling/specialty-units/How much does AC compressor replacement cost for homeowners?
AC compressor replacement pricing is confirmed after an on-site inspection. Costs vary based on your system and the repair scope, and a technician will provide a written estimate before work begins. We offer 24/7 service and financing to help with larger repairs. You can also use our $25 off AC repair coupon (non-stackable; present at service; expires 2025-12-31). We serve Madison, Sun Prairie, Middleton, and nearby.
Quick steps:
- Schedule a diagnostic visit.
- Review the written estimate.
- Ask about 18 Months No Interest, No Payments (Plan #924).
Updated: 2025-12-26 00:00:00
Need help in Cross Plains, WI? Call (608) 313-5510 or book online.
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Where We Work
What areas do you serve for ac repair?
We serve the Greater Madison Area, with frequent service in Madison, Sun Prairie, and Fitchburg. See the full list of communities we cover below.





