HVAC Repair: questions, answered with sources
Each answer cites the public sources it was checked against, with the date it checked them. Jobs that need a licensed pro in Virginia say so, and explain the job instead of teaching it.
AC Not Cooling
3 answers
What should I check before calling for AC repair?
Check the thermostat (Cool mode, fan on Auto, setpoint below room temperature), whether the system's breaker shows tripped, the air filter, the supply vents and the outdoor unit. Those cover the most common no-cooling calls. If you find ice on the lines, water around the indoor unit, hissing, or a tripped breaker, turn the system off at the thermostat and call a licensed HVAC technician.
Why is my AC running but not cooling the house?
When an AC runs but the house stays warm, the fan is moving air but the system is not carrying heat out. The usual causes are a fan set to On, a clogged filter, a dirty outdoor coil, an outdoor unit that has stopped, a frozen indoor coil, a refrigerant leak, leaky ducts, or a system too small for the heat. A licensed technician handles anything inside the equipment.
How do I keep my AC from struggling on hot days?
Give it less heat to fight and a clear path for air. Set the thermostat around 78°F when you are home and avoid dropping it sharply to catch up, keep blinds closed in the afternoon, run the dryer and oven in the cooler hours, check the filter monthly, keep plants and debris away from the outdoor unit, and have a licensed technician service the system in spring, before the heat.
Blower Motor
4 answers
What does replacing a furnace blower motor involve?
It starts with a diagnosis, because a bad capacitor, a clogged filter or a control fault can look like a dead motor. If the motor has failed, a licensed HVAC technician cuts the power, takes the blower assembly out, fits a motor matched to the furnace, rewires it and runs a full heating cycle. A straightforward job takes one to two hours.
How much does a furnace blower motor replacement cost in Virginia?
There is no set Virginia price; licensed HVAC businesses set their own. As a national guide, Carrier put a 2026 blower motor replacement at about $300 to $900, averaging about $560, and Trane gives the same range. The motor type, access, warranty and after-hours rates move the bill. If the fault is only the capacitor, the repair is much smaller.
Is it worth replacing a furnace blower motor?
Usually yes, if the rest of the furnace is sound and not near the end of its life. Bryant says a new motor is usually worth it on a furnace under 10 to 12 years old. Past 10 to 15 years, or when the quote nears half the cost of a new furnace, compare it with replacement. Confirm the motor, not the capacitor, has failed first.
Why is my furnace blower motor humming but not spinning?
A hum with no spin means power is reaching the motor but the shaft cannot start turning. On older furnaces the usual cause is a failed capacitor, the small part that gives the motor its starting push. Worn bearings, a jammed blower wheel or a failing motor can do the same. Switch the furnace off and have a licensed HVAC technician diagnose it.
Boiler Repair
4 answers
What does a boiler technician check when there is no heat?
A technician works from the simple causes to the serious ones: whether the thermostat is calling for heat and the boiler has power, what error code and pressure it shows, whether the circulator is moving water or air is trapped, whether the burner lights and holds a steady flame, and whether the venting, condensate drain and gas supply are clear.
How much does boiler repair cost in Virginia?
Boiler repair has no fixed price, so the bill depends on the diagnosis. You pay for the visit and diagnostic time, then the part and labour, and the part could be an igniter, a sensor, the fan, the main circuit board or the heat exchanger. Warranty coverage can change the bill a lot, so get a written, itemized quote.
Should I repair or replace my boiler?
Repair it when the boiler is under about 15 years old, the heat exchanger is sound and the fault is one replaceable part. Start pricing a replacement when it is past 15 years, needs repairs every season while fuel bills climb, or the heat exchanger has cracked or leaked outside its warranty. Ask the technician to quote both, in writing, so you are comparing real numbers.
Why is my boiler making banging noises?
Banging from inside a hot-water boiler can be kettling: water overheating in the heat exchanger and forming steam bubbles, whose pressure can cause a rumbling or banging noise. Scale restricting flow, low system pressure, trapped air, a pump problem or a faulty thermostat are the causes to check. Banging out in the pipes instead points to the piping. Either way it needs a licensed technician.
Condenser Repair
5 answers
What does replacing an AC condenser involve?
Replacing an AC condenser means a licensed HVAC contractor recovers the refrigerant, removes the outdoor unit, sets a new one, connects the refrigerant lines and wiring, evacuates and charges the system, and tests it. First you decide whether to replace only the outdoor unit or the indoor coil as well. Virginia's code exempts replacing an electric unit in a house from a permit, but issues one on request.
How much does it cost to replace an AC condenser in Virginia?
No Virginia agency publishes a price. When we checked on October 26, 2026, Trane's 2026 national guide put its installed air conditioner replacements at $6,568 to $13,669. The real cost depends on size, efficiency, refrigerant, whether the indoor coil is replaced, line set and electrical work, and the local permit, so compare written quotes.
Should I replace my whole AC system or just the condenser?
Replace only the condenser when the indoor coil and furnace are fairly new, use the same refrigerant and have worked well. Replace the whole system when the equipment is more than 10 years old, needs repeated repairs or never cooled properly. Federal rules allow either, and manufacturers favour a matched indoor and outdoor pair.
Why is my outside AC unit not running?
An outdoor AC unit that will not run usually has one of four problems: the thermostat is not calling for cooling, it has lost power at the breaker, a float switch has shut it down over a clogged drain, or a part such as a capacitor, relay, fan motor or compressor has failed. The first three you can check; the rest need a licensed technician.
How do I keep my outdoor AC unit clear of debris?
Manufacturers advise at least 2 feet of open space around the outdoor unit on every side, leaves, twigs and grass kept off the top and base, mowing that throws clippings away from it, and a dryer vent well away. A winter cover must be breathable and used only while the AC is off. Coil cleaning inside the cabinet is for a technician.
Duct Repair
4 answers
What does repairing damaged ductwork involve?
A licensed HVAC contractor inspects the whole duct system, attic and crawl space included, reconnects or replaces torn, crushed and loose sections, seals joints and registers with mastic or metal tape, insulates ducts in unconditioned space, then checks airflow and, where there are gas or oil appliances, combustion safety. Some Virginia localities require a mechanical permit when ducts are replaced or moved.
How much does duct repair cost in Virginia?
There is no single Virginia price. The bill depends on how much ductwork is damaged, whether it runs through a tight attic or crawl space, whether sections are sealed or replaced, insulation, testing, old asbestos wrap and any permit. Where a permit is needed it is a small part: Spotsylvania County's packet, updated August 2025, lists $147 for an HVAC replacement. Get a written, itemised quote.
Who seals leaking ductwork in a crawl space or attic?
Usually a licensed HVAC contractor: most heating and cooling contractors also repair ductwork, and in Virginia HVAC work for pay needs a licensed tradesman. Home energy auditors and weatherization providers also find and seal duct leaks, often with testing. Whoever you hire, check the licence on DPOR's lookup and ask for leakage testing and a combustion safety check.
Why is my ductwork sweating in the summer?
Ducts sweat when humid air touches a duct surface colder than that air's dew point. In summer a supply duct carries cold air, so humid attic, crawl space or basement air condenses on any bare, thinly insulated or torn spot and around leaky joints. The usual fixes are sealing the leaks, restoring insulation with an intact vapor retarder, and drying out the space.
Frozen Coil
4 answers
What should I do if my AC coil freezes up?
Turn the cooling off at the thermostat and, if your system allows it, set the fan to On so moving air helps the ice melt. Do not chip at the ice. Put towels or a pan down for the meltwater, change a dirty filter and open any blocked vents. Restart only once it has fully thawed, and call a licensed HVAC technician if it freezes again.
How much does it cost to fix a frozen AC coil in Virginia?
It depends on why the coil froze. A clogged filter or blocked vents costs no more than a new filter. A service visit adds a call fee, which Trane put at an average of $50 to $200 in May 2026, plus labor. A refrigerant leak costs more, and in June 2025 American Standard put an out-of-warranty coil replacement at about $800 to $3,500.
Why does my AC coil keep freezing?
An AC coil freezes when its surface drops below 32°F and the moisture on it turns to ice. When it keeps happening, the usual causes are restricted airflow, from a dirty filter, closed or blocked vents, a dirty coil or a weak blower, or low refrigerant from a leak. Running the AC on cool days below about 60°F and a faulty thermostat can also do it.
How do I keep my AC coil from freezing?
Keep warm air moving across the coil and the refrigerant sealed in. Check the filter monthly in cooling season and change it when dirty, keep supply and return vents open and clear, avoid running the AC when it is below about 60°F outside, and have a licensed technician clean the coil, check the refrigerant and adjust the blower each spring.
Furnace Not Heating
4 answers
Is it safe to relight a furnace pilot light myself?
Furnace makers say yes in one narrow case: the furnace has a standing pilot, you smell no gas, and you follow the manufacturer's lighting instructions for that model. Many furnaces have no pilot at all. For a gas smell or a carbon monoxide alarm, leave the house and call 911 and your gas company. For a pilot that keeps going out, call a licensed HVAC technician.
How much does it cost to fix a furnace that won't heat in Virginia?
There is no set Virginia price. Licensed HVAC businesses set their own rates, and a no-heat call costs a diagnostic visit plus whatever failed: little more than the visit for a thermostat setting or clogged filter, and a part plus labour for an igniter, flame sensor, gas valve, blower motor or control board. Get the diagnosis and an itemized price in writing before approving work.
Why is my furnace running but not heating?
Usually the blower is running while the burners are off. The common reasons are a thermostat fan set to On, a clogged filter or closed vents that tripped the high-limit switch, a pilot, igniter or flame sensor fault, no fuel, a blocked condensate drain or vent pipe on a high-efficiency furnace, or a failing control board. Leaky ducts make warm air arrive lukewarm.
What should I check on my furnace before winter?
Before the first cold night, check the filter, set the thermostat to Heat and make sure the furnace runs and warms the house, test your carbon monoxide alarms, clear flammables away from the furnace, and look at the outside vent pipes and your fuel level. Then book a licensed HVAC technician for the fall check-up of the burners, gas connections, heat exchanger and controls.
Heat Pump Repair
4 answers
What does a heat pump repair visit involve?
A repair visit has three parts. The technician confirms what the system is doing wrong, tests it from the thermostat through the indoor unit to the outdoor unit until the faulty part turns up, then explains the fault and quotes the repair before doing it. Most faults trace to controls, electrical parts, airflow, refrigerant or the defrost system, and that work is licensed in Virginia.
How much do common heat pump repairs cost in Virginia?
Virginia has no set price list: each licensed HVAC business sets its own, and a bill is usually a service call fee plus parts and labor. Trane's general estimates, not specific to Virginia (August 2024, updated February 2026), run from $100-$400 for a capacitor and $200-$700 for a fan motor to $900-$2900 for a compressor. Refrigerant type, age, warranty and after-hours calls move the total.
How old is too old for a heat pump?
There is no fixed cut-off. Manufacturers put a typical heat pump's life anywhere from 10 to 12 years (Trane) to 15 to 20 (Carrier), and ENERGY STAR suggests considering replacement once a heat pump is more than 10 years old. Age matters most alongside repair costs, rising bills, R-22 refrigerant and warranty status, so a working older unit is not automatically too old.
Why is my heat pump covered in ice?
A thin layer of frost is normal in cold, damp weather, and the heat pump clears it with a short defrost cycle. A unit encased in ice is not normal. The usual causes are blocked airflow, water dripping onto the unit from a gutter, a failed defrost control or sensor, a bad outdoor fan motor, or low refrigerant from a leak, and most of those need a licensed technician.
Mini-Split Repair
4 answers
What does a mini-split repair visit involve?
A mini-split repair visit has three parts. The technician confirms the symptom and reads any fault code, tests the system from the controls through the indoor head to the outdoor unit until the failed part turns up, then explains the fault and prices the repair before doing it. Most faults trace to airflow, the drain, electrical parts, refrigerant or the compressor, and that work is licensed in Virginia.
How much does mini-split repair cost in Virginia?
No Virginia agency we checked publishes mini-split repair prices, so the bill comes down to a diagnostic fee, labour and the part. In Trane's August 2024 heat pump repair estimates, which cover ducted and ductless systems, a service call ran $50-200, a capacitor $100-$400 and a compressor $900-$2900. Refrigerant, the number of indoor units and warranty coverage move the total, so get a written, itemized quote.
Should I repair or replace my mini-split?
Repair is usually the better buy when the mini-split is under about 10 years old, the fault is one part and the repair costs well under half the price of a new system. Price a replacement when the unit is past 10 to 15 years, the compressor or a coil has failed, repairs keep coming, or it runs on R-22. Get both prices in writing from a licensed contractor.
Why is my mini-split blinking and not cooling?
A blinking light on the indoor unit is usually the mini-split reporting a fault code: it has detected a problem, such as lost communication with the outdoor unit, a failed sensor, an overheated compressor or low refrigerant, and stopped cooling to protect itself. Count the blinks, look the pattern up in your model's manual, check the settings and filters, and call a licensed HVAC technician if the code returns.
Refrigerant Leak
4 answers
How is a refrigerant leak found and fixed?
A certified HVAC technician finds the leak with an electronic detector, UV dye or bubble solution, recovers the remaining refrigerant, then repairs the leaking tubing or fitting or replaces the leaking coil. The repaired circuit is pressure-tested with nitrogen, evacuated with a vacuum pump and recharged to the manufacturer's specified amount. Adding refrigerant without finding the leak is not a repair.
How much does it cost to fix a refrigerant leak in Virginia?
It depends on where the leak is, which refrigerant the system uses and how many pounds it needs. A tightened fitting is a small bill; a replaced coil or line set is a large one. Trane's May 2026 national guide puts evaporator coil work at $1,000 to $5,000 or more, and its 2025 guide puts R-410A at $40 to $90 a pound installed. Get a written, itemised quote.
Can a homeowner buy refrigerant to recharge their own AC?
Not for a home central air conditioner or heat pump. Under the EPA's Section 608 rules, refrigerant for stationary systems is sold only to certified technicians or the companies that employ them, and recharging requires that certification. The small cans sold over the counter are for car air conditioners. A low charge means a leak, so hire a certified, Virginia-licensed HVAC technician to find and fix it.
How do I know if my AC is low on refrigerant?
The usual signs are warm or weak air, an AC that runs and runs without reaching the setpoint, ice on the indoor coil or outdoor line, a hissing or bubbling sound, a sticky house and higher bills. A dirty filter or thermostat setting can cause the same symptoms, so none proves a leak. Only a certified technician can confirm the charge.
Thermostat Repair
1 answer
Water Heater Repair
1 answer