Frequently Asked Questions
General HVAC Questions
How often should HVAC systems be serviced?
HVAC systems should be serviced twice per year — once in the spring for your air conditioner and once in the fall for your heating system. Regular maintenance improves efficiency, reduces breakdowns, and extends equipment lifespan.
How long do HVAC systems last?
Most HVAC systems last 10–15 years. Furnaces may last up to 20 years with proper maintenance, while air conditioners and heat pumps typically last 10–15 years.
How do I know if I need HVAC repair or replacement?
If your system is over 10–15 years old, requires frequent repairs, or causes high energy bills, replacement may be more cost-effective. New systems offer improved efficiency and reliability.
What are the most common HVAC problems?
Common issues include dirty filters, refrigerant leaks, thermostat malfunctions, electrical problems, and worn components. Regular maintenance helps prevent these problems.
Why is my HVAC system running but not heating or cooling properly?
This may be caused by restricted airflow, low refrigerant, thermostat issues, or component failure. A professional inspection can identify and fix the issue.
Air Conditioning FAQs
Why is my air conditioner not cooling properly?
This could be due to dirty coils, low refrigerant, airflow problems, or thermostat issues. Professional service can restore proper cooling performance.
How often should AC maintenance be performed?
Air conditioners should be serviced once per year, ideally in early spring before the cooling season begins.
How long do air conditioners last in Raleigh, NC?
Air conditioners typically last 10–15 years, depending on maintenance, usage, and environmental conditions.
What temperature should I set my thermostat in summer?
The U.S. Department of Energy recommends setting your thermostat to 78°F when you’re home to balance comfort and efficiency.
Why is my AC freezing up?
Frozen AC units are often caused by restricted airflow, dirty filters, refrigerant issues, or blower problems.
Heating System FAQs
Why is my furnace not heating properly?
This may be caused by thermostat problems, dirty filters, ignition issues, or worn components.
How often should heating systems be serviced?
Heating systems should be serviced once per year, preferably in the fall before cold weather begins.
How long do furnaces last?
Most furnaces last 15–20 years with proper maintenance.
Why is my furnace making unusual noises?
Unusual noises may indicate loose parts, airflow problems, or mechanical wear. Professional inspection is recommended.
Heat Pump FAQs
What is a heat pump?
A heat pump provides both heating and cooling using electricity. It transfers heat instead of generating it, making it highly efficient.
How long do heat pumps last?
Heat pumps typically last 10–15 years with regular maintenance.
Why is my heat pump running constantly?
Heat pumps may run longer in extreme temperatures, but constant operation may indicate efficiency or system issues.
Maintenance and Efficiency FAQs
Do you offer HVAC maintenance agreements in Raleigh, NC?
Yes, Design Mechanical offers planned maintenance agreements that include inspections, cleaning, and performance optimization.
How can I lower my HVAC energy bills?
Regular maintenance, replacing filters, upgrading to a smart thermostat, and installing high-efficiency equipment can reduce energy costs.
How often should air filters be replaced?
Most air filters should be replaced every 1–3 months, depending on usage, pets, and indoor air quality.
Does HVAC maintenance really save money?
Yes, maintenance improves efficiency, reduces breakdowns, and extends system life, saving money long-term.
Thermostat FAQs
Do smart thermostats really save money?
Yes, smart thermostats can reduce energy use by automatically adjusting temperatures based on your schedule.
Can you install Nest, EcoBee, and Honeywell thermostats?
Yes, Design Mechanical installs and services all major smart thermostat brands.
Why is my thermostat not working properly?
Thermostat issues may be caused by wiring problems, battery failure, or calibration issues.
Indoor Air Quality FAQs
How can I improve indoor air quality?
Installing better air filters, improving ventilation, controlling humidity, and maintaining your HVAC system can improve air quality.
Do whole house air filters help?
Yes, whole house air filters reduce dust, allergens, and airborne contaminants throughout your home.
What causes poor indoor air quality?
Dust, pet dander, poor ventilation, dirty filters, and humidity issues can affect air quality.
Installation and Service FAQs
How long does HVAC installation take?
Most HVAC installations can be completed in one day, depending on the system and home.
How do I know what size HVAC system I need?
A professional load calculation ensures your system is properly sized for efficiency and comfort.
Do you offer HVAC installation in Raleigh, NC?
Yes, Design Mechanical provides HVAC installation services throughout Raleigh and surrounding areas.
What areas do you serve?
We serve Raleigh, Cary, Apex, Wake Forest, and surrounding communities.
Do you offer emergency HVAC repair?
Yes, we provide fast, reliable HVAC repair services to restore your comfort quickly.
Why should I choose Design Mechanical for HVAC service?
Design Mechanical provides professional HVAC installation, repair, and maintenance in Raleigh, NC. Our experienced technicians deliver reliable service, efficient solutions, and long-term comfort.