HVAC Installation in Herndon, VA
A new system here will heat from October through April and cool from June through September every year. Tell us about the house, and a licensed contractor who covers Fairfax County will get in touch.
Tell us about the job
It takes about a minute.
Herndon asks for both, most of the year
Your new system has to handle heat from October through April and cooling from June through September, 11 months out of the year with barely a break between them. Winter nights average 28°F from December through February, cold enough that a furnace or heat pump settles into long, steady cycles most nights. Summer afternoons average 86°F, and the same system has to switch over and hold that ground through the summer months.
More than half the homes here heat with gas, so a lot of installations pair a furnace with a separate air conditioner rather than running one heat pump for both jobs. Whichever setup goes in, it has to meet the current federal minimum efficiency, so installation is also the moment to decide whether to install right at that minimum or above it.
- 7 months
- October through April, your system heats
- 4 months
- June through September, it cools
- 28°F
- the average winter night it heats against
- 86°F
- the average summer afternoon it cools against
NOAA nClimDiv, 1991–2020 normals
Virginia requires HVAC contractors to hold a state license.
The Board for Contractors is the one that licenses HVAC contractors in Virginia. The license belongs to the contractor, not to any single job. It's the same license whether they're doing yours or the next one down the street. Virginia sets one exception. Work under $1,000 doesn't need a licensed contractor at all. An installation like yours will always be above that line.
Most cities and counties also want a permit before an installation starts and an inspection once it's done. That inspection is separate from the state license. It's what catches a bad gas connection or a system that wasn't set up right, and it's done by the local building office rather than the state board.
Sources: Virginia General Assembly · Virginia Department of Professional and Occupational Regulation
- When should I replace my HVAC system?
- Replace it when it's breaking down more than once a season or when repairs keep piling up instead of solving anything. A system that's short-cycling, making new noises, or can't keep the house warm on the coldest nights or cool through a 86°F afternoon is telling you it's done. Homes here need heat from October through April and cooling from June through September, so there's only a short stretch each year when a failing system won't be tested right away. Better to replace it on your schedule than have it quit on the coldest night of the winter.
- Should I replace my furnace and air conditioner at the same time?
- If they're close in age, yes, it usually makes sense to do both together. A furnace and air conditioner installed at the same time are matched to work with each other, and replacing one while the other is old often means you're back for the second job before long anyway. If your furnace is failing but the air conditioner is still young, replacing just the furnace is reasonable. A contractor can look at the age and condition of both and tell you whether pairing them makes sense for your house.
- What happens during an HVAC installation?
- A contractor removes the old furnace, air conditioner or heat pump and sets the new equipment in place, then connects it to your ductwork, electrical, gas line or refrigerant lines depending on what's being installed. They test the system afterward to make sure it's heating or cooling correctly, checking things like airflow before calling the job done. Virginia requires HVAC contractors to hold a state license for this kind of work, and most cities and counties also require a permit and an inspection once the installation is finished. A contractor will price the job once they've seen the house and know what the installation involves.