HVAC Repair Desk

Repairs

35 guides

When a heating or cooling system quits or starts acting up, the repairs hub helps you tell a quick fix from a major job before a technician ever quotes a price.

See every guide
An outdoor air conditioner with its service panel removed and hand tools laid out on the grass

What this covers

  • Systems covered: central AC, furnaces, heat pumps, ductless mini-splits, and boilers
  • Read your symptom first: no cooling, no heat, short cycling, weak airflow, odd noises, or burning and musty odors
  • The parts that fail most: capacitors, contactors, blower motors, control boards, and refrigerant circuit components
  • What moves a repair bill: the failed component, system type, equipment age, and peak-season or after-hours timing
  • Which checks are safe to try yourself and which require an EPA 608 certified technician
  • How to read a diagnostic and get an itemized quote before approving any work

All repairs guides

Close-up of frosted copper refrigerant lines on an air conditioner evaporator coilRepairs · 8 minAC Freezing Up: Causes of a Frozen AC Unit and How to Fix ItA white PVC condensate drain line and a small condensate pump beside an indoor air handlerRepairs · 11 minAC Refrigerant Leak: Signs, How Leaks Are Found, and AC Recharge CostA dual run capacitor and a contactor wired inside an outdoor AC electrical panelRepairs · 8 minAC Short Cycling: Why Your AC Turns On and Off FrequentlyAn outdoor air conditioner with its service panel removed and hand tools laid out on the grassRepairs · 9 minAC Unit Not Turning On: How to Find Out WhyBlue gas burner flames inside a furnace, with the flame sensor and ignitor beside themRepairs · 9 minCracked Heat Exchanger: Signs, Carbon Monoxide Risk and What to DoA thermostat glowing orange in a dark hallway on a hot summer nightRepairs · 9 minEmergency Heat on Your Thermostat: What It Does, When to Use It and How It Differs From Aux HeatClose-up of frosted copper refrigerant lines on an air conditioner evaporator coilRepairs · 10 minFreon in Your AC: What It Is, AC Refrigerant Types, and What ChangedA modern gas furnace with a blue burner flame in a bright basement, snow outside the windowRepairs · 8 minFurnace Blowing Cold Air: Causes, Checks and When to StopBlue gas burner flames inside a furnace, with the flame sensor and ignitor beside themRepairs · 10 minFurnace Flame Sensor: How It Works, How to Clean It, and When to Replace ItHands sliding a clean pleated air filter into a furnace, with the old dusty filter beside itRepairs · 8 minFurnace Ignitor: How Hot Surface Ignitors Fail and What Replacement InvolvesBlue gas burner flames inside a furnace, with the flame sensor and ignitor beside themRepairs · 8 minFurnace Limit Switch: What It Does and Why It Keeps TrippingA modern gas furnace with a blue burner flame in a bright basement, snow outside the windowRepairs · 8 minFurnace Pilot Light Out? How to Relight It and Why It Won't Stay LitClose-up of frosted copper refrigerant lines on an air conditioner evaporator coilRepairs · 8 minR22 Refrigerant: The Phase Out, What Repairs Cost, and Your Replacement OptionsAn outdoor air conditioner with its service panel removed and hand tools laid out on the grassComparison · 8 minR32 Refrigerant vs R454B: How They Differ and Which Matters for Your New SystemA dual run capacitor and a contactor wired inside an outdoor AC electrical panelRepairs · 10 min410A Refrigerant (R-410A): The Phase Out, Repairs, and What to Do NextA dual run capacitor and a contactor wired inside an outdoor AC electrical panelRepairs · 11 minAC Capacitor: What It Does, Signs It's Failing, and Replacement CostClose-up of frosted copper refrigerant lines on an air conditioner evaporator coilRepairs · 11 minAC Condenser: What the Outdoor Unit Does, Common Problems, and Repair vs ReplaceAn outdoor air conditioner with its service panel removed and hand tools laid out on the grassRepairs · 11 minAC Contactor: What It Does, Signs It's Failing, and ReplacementA white PVC condensate drain line and a small condensate pump beside an indoor air handlerRepairs · 11 minCondensate Pump Guide: How It Works, Why It Fails, and How to Replace OneA dual run capacitor and a contactor wired inside an outdoor AC electrical panelRepairs · 11 minCondenser Fan Motor Not Working? Symptoms, Why the AC Fan Won't Spin, and ReplacementClose-up of frosted copper refrigerant lines on an air conditioner evaporator coilRepairs · 11 minEvaporator Coil Guide: How It Works, Dirty vs Leaking, and Replacement CostA white PVC condensate drain line and a small condensate pump beside an indoor air handlerRepairs · 14 minAC Leaking Water Inside: Causes, Fixes, and When to Shut It OffA modern gas furnace with a blue burner flame in a bright basement, snow outside the windowRepairs · 12 minFurnace Blower Motor Failing? Symptoms, PSC vs ECM, and Repair vs ReplaceAn outdoor air conditioner with its service panel removed and hand tools laid out on the grassRepairs · 12 minAC Not Cooling or Blowing Warm Air: How to Find the CauseA clipboard with an estimate, a pen and a calculator resting on a new outdoor AC unitCost guide · 6 minHow Much Does AC Repair Cost?A new outdoor heat pump on a concrete pad beside a modern wood-sided homeRepairs · 5 minBest AC Repair CompaniesA modern gas furnace with a blue burner flame in a bright basement, snow outside the windowRepairs · 12 minWhy Is My Furnace Not Working?A dual run capacitor and a contactor wired inside an outdoor AC electrical panelRepairs · 10 minAC Compressor Repair: Warning Signs, Diagnosis and Repair vs ReplaceAn outdoor air conditioner with its service panel removed and hand tools laid out on the grassRepairs · 9 minAC Repair: Common Problems, Likely Causes and What to Check FirstA wall-hung condensing boiler with copper pipes and a red circulator pump below itRepairs · 9 minBoiler Repair: Diagnosing a Hot Water Boiler, From Low Pressure to Cold RadiatorsA modern gas furnace with a blue burner flame in a bright basement, snow outside the windowRepairs · 10 minFurnace Repair: What Fails, What to Check First, and When to ReplaceAn outdoor heat pump running in light snow beside a house with a warm lit windowRepairs · 9 minHeat Pump Repair: Common Problems, Cost Factors and What to Check FirstBlue gas burner flames inside a furnace, with the flame sensor and ignitor beside themRepairs · 9 minHeating Repair: Find the Problem by System Type and Stay Safe Without HeatA new outdoor heat pump on a concrete pad beside a modern wood-sided homeRepairs · 8 minHVAC Repair Guide: Narrow the Problem to Heating, Cooling, Airflow or ControlsA white ductless mini split head mounted high on a bright bedroom wallRepairs · 9 minMini Split Repair: Error Codes, Leaks, Common Problems and What to Check First

About this topic

It covers diagnostics and repair for central air conditioners, furnaces, heat pumps, ductless mini-splits, and boilers, along with the specific failures homeowners run into most: a unit that runs but blows warm air, a compressor that will not start, a furnace that ignites and shuts off, short cycling, weak airflow, and strange noises or smells. You will find guidance on the parts that fail most often, such as capacitors, contactors, blower motors, and control boards, plus what refrigerant leaks and coil problems actually involve. Cost pages here explain the factors that move a bill rather than promising a flat rate, because the real number depends on the failed component, system type, equipment age, and whether you call during peak season or after hours. Refrigerant and electrical work are regulated and belong with a licensed, EPA 608 certified technician, so the guides also flag which checks are safe for a homeowner and which are not. Read up on your symptom and understand what a fair diagnostic looks like before you approve any repair quote.

Repairs questions

How much does an HVAC repair cost?

There is no flat rate, because the bill depends on what failed. A capacitor or contactor swap and a clogged drain line clear sit at the low end. Refrigerant leak repair, a blower motor, or a control board run higher, and compressor or heat exchanger work is the most expensive. System type, equipment age, your local labor rates, and whether you call after hours or in peak season all shift the total. Ask for an itemized quote that separates the diagnostic fee, parts, and labor before you approve the work.

Is it safe to try any repairs myself first?

A few checks are homeowner-safe and worth doing before you call. Confirm the thermostat is set correctly, reset a tripped breaker once, replace a visibly clogged filter, and make sure the outdoor disconnect is on. Beyond that, stop. Refrigerant handling is federally regulated under EPA 608, and electrical work or anything inside the air handler carries real shock and fire risk. If a breaker trips a second time, or you smell burning, shut the system off and let a licensed technician trace the fault.

How long will a repair take?

Most repairs finish in a single visit of roughly one to three hours once the technician diagnoses the fault and has the part on the truck. Common components like capacitors, contactors, and motors are usually stocked. A repair that needs a special-order part for an older or uncommon system can take a few extra days between diagnosis and completion. If your system is down in dangerous heat or cold while you wait for a part, ask the contractor about a temporary fix or emergency options.