HVAC FAQ

Why is my furnace not heating?

Common causes include thermostat issues, dirty filters, pilot light problems, or a faulty ignition system. First, check your thermostat settings and ensure it's set to "heat" and the temperature is above current room temperature. Replace your air filter if it's dirty. Check if the pilot light is lit (for older furnaces). If these simple fixes don't work, contact a professional HVAC technician.

How often should I change my HVAC filter?

Replace standard 1-inch filters every 1-3 months. High-efficiency filters can last 6-12 months. Check your filter monthly and replace when visibly dirty. Homes with pets, allergies, or high dust levels may need more frequent changes. A dirty filter reduces efficiency and can damage your system.

Why is my AC blowing warm air?

This could be due to low refrigerant, a dirty condenser coil, thermostat issues, or a frozen evaporator coil. Check that your thermostat is set to "cool" and the temperature is below current room temperature. Ensure the air filter is clean and the outdoor unit isn't blocked by debris. If the problem continues, you likely have a refrigerant leak or mechanical issue requiring professional repair.

How much does HVAC repair cost?

Costs vary widely based on the issue:

• Minor repairs: $150-$500 (thermostat, filters, minor electrical)
• Medium repairs: $500-$1,500 (blower motor, capacitor, sensor)
• Major repairs: $1,000-$2,500 (compressor, heat exchanger)
• Emergency service: Add $100-$300 for after-hours calls

Use our AI triage tool for a cost estimate based on your specific issue.

When should I replace my HVAC system?

Consider replacement if:

• System is over 15 years old
• Frequent repairs (more than 2-3 per year)
• Rising energy bills despite no usage changes
• Repair costs exceed 50% of replacement value
• Uneven heating/cooling throughout home
• System uses R-22 refrigerant (being phased out)

Modern systems are 20-40% more efficient and include smart features.

What is HVAC maintenance and how often do I need it?

HVAC maintenance includes professional inspection, cleaning, and tune-up of your system. Schedule maintenance twice yearly:

• Spring: AC tune-up before summer
• Fall: Heating system tune-up before winter

Benefits of regular maintenance:

• Prevents 95% of system breakdowns
• Extends system lifespan by 5-10 years
• Maintains peak efficiency and lower energy bills
• Maintains manufacturer warranty coverage

What's the difference between a furnace and a heat pump?

A furnace generates heat by burning fuel (gas, oil, propane) or using electric resistance. A heat pump transfers heat from outside air (even in cold weather) into your home. Heat pumps are more efficient but may need backup heat in very cold climates. Heat pumps can also cool your home in summer.

Why is my HVAC system making strange noises?

Different noises indicate different issues:

• Banging/clanging: Loose parts or ductwork
• Squealing: Belt or motor bearing issues
• Hissing: Refrigerant leak or air duct leak
• Clicking: Electrical relay or control issue
• Rattling: Debris in unit or loose components

Unusual noises should be inspected promptly to prevent damage.

Can I repair my HVAC system myself?

Safe DIY tasks include:

• Changing air filters
• Adjusting thermostat settings
• Cleaning around outdoor unit
• Checking circuit breakers
• Clearing drain lines (if accessible)

Never attempt: opening refrigerant lines, electrical repairs, gas line work, or removing safety covers. These require licensed professionals and can be dangerous.

What size HVAC system do I need?

Proper sizing requires a professional load calculation considering:

• Square footage and layout
• Insulation quality
• Window types and orientation
• Climate zone
• Occupancy and heat-generating appliances

An oversized system cycles on/off too frequently, reducing efficiency and comfort. An undersized system can't maintain temperature and runs constantly.