Hollins, VA HVAC Repair: AC Runs but Won’t Cool

Estimated Read Time: 12 minutes

Is your AC running but not cooling? You hear the system humming, yet the house still feels like a July afternoon in Roanoke. Here is the good news: most no-cool issues trace back to seven common causes. Use this guide to spot quick fixes you can do safely and learn when to call a pro for reliable HVAC repair. Free estimates are available if you need us.

1) Dirty or Clogged Air Filter

A clogged filter chokes airflow, so your coil cannot absorb heat and your AC runs without lowering the temperature. In spring around Roanoke and Salem, pollen can load a filter in weeks.

What to do now:

1. Check the filter size and orientation. Replace if it looks gray, matted, or you cannot see light through it.
2. Use the correct MERV rating for your system. Too high can restrict airflow.
3. Set reminders to change filters every 30 to 90 days based on pets, allergies, and renovation dust.

Why it matters:

• ENERGY STAR notes typical duct systems and airflow issues can cost 20 to 30 percent of conditioned air, and a dirty filter makes that worse by starving the blower.
• Low airflow can cause coil icing, which further kills cooling and can damage the compressor.

Callout from a recent job: “I was really pleased by my experience... Johnnie was very knowledgeable and got my AC back up and running quickly!”

2) Thermostat or Settings Problems

Your AC can run without cooling if the thermostat is set wrong or failing. Simple oversights are common during seasonal changes in Cave Spring and Vinton.

Quick checks:

1. Make sure it is set to Cool, not Heat or Fan Only.
2. Set temperature at least 3 degrees below room temp for a real test.
3. Replace thermostat batteries annually. Weak batteries cause erratic behavior.
4. Confirm the schedule is not overriding your set point.

If you have a heat pump, verify the reversing valve is switching modes. A stuck valve can make it feel like nothing is happening even though the outdoor unit runs. Many smart thermostats need a proper C-wire connection. If your screen goes blank or reboots, schedule a pro visit.

Customer note: “They came out right away and took care of the issue. Super knowledgeable and polite.”

3) Frozen Evaporator Coil

If the indoor coil freezes, your AC will blow little to no cold air. Ice signals low airflow or low refrigerant.

How to identify:

• Weak supply airflow and warm return grill.
• Visible frost on the indoor coil or refrigerant lines.
• Water near the air handler after it thaws.

What to do safely:

1. Turn the system off and set the fan to On for 2 to 3 hours to thaw.
2. Replace the filter and clear supply and return vents.
3. After thawing, turn cooling back on. If ice returns, you likely have a refrigerant or blower problem that needs a technician.

Hard fact: EPA regulations ended production and import of R‑22 refrigerant in the U.S. in 2020. If your older system uses R‑22, a leak is more expensive to address than with modern R‑410A units. That often tilts the math toward replacement.

4) Refrigerant Leaks or Incorrect Charge

Your AC does not “use up” refrigerant. If it is low, there is a leak. Low charge means the system absorbs less heat, so it runs and runs without satisfying the thermostat.

Symptoms:

• Longer cycles and lukewarm air.
• Hissing or bubbling at line sets or coil.
• Ice on the outdoor or indoor lines.

What a pro does:

1. Perform electronic leak detection and visual dye testing.
2. Repair the leak. Topping off without repair is a short-term patch and often violates best practices.
3. Weigh in the correct charge to manufacturer specs. Proper charge restores capacity and protects the compressor.

When to consider replacement:

• A major leak on an R‑22 system.
• Repeated leaks on a coil older than 10 years.

Review snippet: “Great work done by David and Johnnie... New HVAC work looks great and runs smooth with low noise!!”

5) Outdoor Unit Blocked or Dirty

The outdoor condenser has one job: dump heat. If it is covered in debris or packed with grass clippings from a Saturday mow in Hollins, it cannot reject heat, so the system runs without cooling.

DIY steps:

1. Turn off power at the disconnect.
2. Gently rinse the coil from inside out with a hose. Do not use high pressure.
3. Trim vegetation to keep 2 feet of clearance on all sides and 5 feet above.
4. Level the pad if the unit has sunk or tilted, which can stress lines and fan bearings.

Why it matters:

• Manufacturer guidance typically requires at least 24 inches of clearance for proper airflow.
• A clean coil lets the condenser move heat efficiently, preventing high pressure trips and extending compressor life.

Customer feedback we hear often: “The entire crew... was professional and completed the job without issues. I highly recommend this company.”

6) Blower or Ductwork Problems

If the blower is weak or ducts are leaky, conditioned air never reaches the rooms. The system runs, electric meter spins, but comfort never arrives.

What to check:

• Listen for the indoor blower. If it hums but does not start, a failed capacitor or motor could be the cause.
• Walk your home. Closed or blocked vents starve rooms. Open them fully.
• Look for disconnected or crushed flex duct in attics or crawlspaces common around Christiansburg and Rocky Mount.

Hard fact: ENERGY STAR estimates typical duct systems lose 20 to 30 percent of airflow through leaks and poor design. Sealing and balancing brings a double benefit: better comfort and lower bills.

When to call Bob Garrett Services:

1. Uneven temperatures between floors.
2. Hot rooms at the end of long runs.
3. Visible duct gaps or kinks.

7) Safety Switches, Drain Issues, or Electrical Faults

Modern systems protect themselves. If a float switch senses a clogged condensate drain, it will cut cooling to prevent water damage. Likewise, breaker trips or a failed contactor can leave the air handler running while the outdoor unit is off.

Homeowner checklist:

1. Check the breaker panel for tripped AC or air handler breakers. Reset once only.
2. Inspect the condensate line near the indoor unit. If the pan is full, have the drain cleared and treated.
3. Listen outside. If the indoor fan runs but the outdoor unit is silent, you may have a failed capacitor or contactor that needs a technician.

Pro tip for Roanoke summers: algae grows fast in warm drain lines. Prevent clogs with routine maintenance that includes drain cleaning and treatment.

When Repair Makes Sense vs Replacement

Repair is usually best when the system is under 10 years old, the fix is minor, and parts are available. Replacement can be smarter if:

• The system uses R‑22 and has a major leak.
• The compressor or coil fails out of warranty.
• Your repair costs exceed 25 to 30 percent of a new system quote.

What you gain with replacement:

1. Higher SEER2 efficiency for lower bills.
2. Quieter operation and improved humidity control.
3. Warranty coverage that caps future risk.

Homeowner note: “Shaun and David... inspected our HVAC and furnace when it wasn’t keeping up with the thermostat... took care of the issue.”

DIY Fixes You Can Try Before Calling

These safe steps solve many no-cool calls in minutes:

1. Replace the filter and open all vents.
2. Set thermostat to Cool, Auto fan, and a 3-degree difference.
3. Clear debris from the outdoor unit and ensure 2 feet of clearance.
4. Thaw a frozen coil by turning cooling Off and fan On for 2 hours, then retry.
5. Check breakers once and reset if tripped.

Stop if you see ice, hear grinding, smell burning, or the breaker trips again. Those are signs you need a professional.

Why Bob Garrett Services for HVAC Repair in Greater Roanoke

You want fast diagnosis, straight answers, and no surprises. That is how we work.

• Certified technicians service all brands and install high-quality Carrier systems.
• Free estimates for repairs and replacements. Transparent pricing before we start.
• Local expertise across Roanoke, Salem, Vinton, Blacksburg, Christiansburg, and nearby communities like Hardy and Wirtz.
• Thorough repairs that address root causes, including refrigerant leaks, airflow problems, and safety switch faults.

Recent praise from homeowners: “Prompt, knowledgeable... took the time to thoroughly assess my home’s cooling needs.”

Preventative Maintenance That Actually Prevents No-Cool Calls

Seasonal tune-ups keep you comfortable and catch small issues before they snowball in July heat.

What our maintenance visits include:

1. Full system inspection, electrical testing, and safety checks.
2. Coil and drain cleaning, refrigerant performance test, and airflow verification.
3. Thermostat calibration and ductwork assessment for leaks and balance.

What you get:

• Fewer breakdowns during peak heat.
• Lower energy costs through restored capacity and efficiency.
• Documentation for warranty compliance and home sale records.

Note: Many manufacturers require proof of routine maintenance to honor parts warranties. Keeping records protects your investment.

Special Offer: Free Estimate on HVAC Repair

Get a free estimate on HVAC repair or replacement. Request yours before 2026-02-04. Call 540-583-4765 or visit https://bobgarrettservices.com/ to schedule. Mention this offer when you call to prioritize your booking.

Frequently Asked Questions

Why is my AC running but not cooling after a filter change?

If the coil froze before you changed the filter, ice may still block airflow. Turn cooling Off, fan On for 2 hours, then retry. If it refreezes, you may have a refrigerant or blower issue.

Can low refrigerant cause the AC to run constantly?

Yes. Low charge reduces heat absorption, so the system runs longer without reaching set point. A pro must find and repair the leak, then weigh in the correct charge.

How often should I change my AC filter in Roanoke?

Every 30 to 60 days in peak pollen season or with pets. Otherwise, every 60 to 90 days. Check monthly and replace when dirty.

Is it safe to rinse my outdoor unit?

Yes, after cutting power at the disconnect. Use a gentle hose stream from inside out. Do not use high pressure, which can bend fins.

When should I replace instead of repair?

Consider replacement if the system uses R‑22, has a major leak, is over 12 years old, or repair costs exceed 25 to 30 percent of a new system price.

Conclusion

When your AC is running but not cooling, the cause is usually airflow, refrigerant, or a control issue. Use the steps above to rule out quick fixes and call a pro when signs point to a deeper problem. For fast help with AC running but not cooling in Roanoke and nearby cities, we are ready to restore comfort today.

Call, Schedule, or Chat Now

• Call 540-583-4765 for same-day HVAC repair in Roanoke, Salem, Vinton, Blacksburg, Christiansburg, and beyond.
• Schedule at https://bobgarrettservices.com/ for a free estimate before 2026-02-04.
• Prefer messaging? Use our website contact form and mention “Free Estimate” to lock in the offer.

Bob Garrett Services keeps homes comfortable across Greater Roanoke with certified HVAC, generator, plumbing, and electrical pros. We pair factory-trained technicians with upfront pricing, on-time arrivals, and clean work. We service all major HVAC brands, install premium Carrier systems, and back our work with clear guarantees. Local, responsive, and trusted, our team delivers free estimates and honest recommendations that fit your home and budget.