Replacing or upgrading major equipment can be nerve-wracking, and HVAC systems are no different. You want to make a choice that you won’t regret later and you have so many questions. We’ve covered the most frequently asked questions homeowners have here so that you don’t have to do too much digging around.


Heating and Air Con FAQs


How Long Does a Standard Furnace and AC Last?

Good furnaces can be expected to last 20-30 years and stand-alone air conditioning units usually last an average of 10-15 years. The durability of your units is tempered by many factors such as the overall amount of use, the climate in your location, whether you have been doing regular maintenance, and of course, the quality of the system you have.


How Can I Tell If It’s Better to Repair or to Replace My Unit or System?

There are a few considerations to help you make that decision. How old is your equipment? How much would repairs cost? If your system is more than 10 years old and in constant need of repairs, it may be more cost-efficient to replace the system altogether or at least upgrade some of the hardware.

Also, consider the type of repairs needed. If your air conditioner is leaking refrigerant, replacement might a better option than the expensive cost of repair. Take into account the energy consumption of your current unit versus a newer model. A large outlay now may save you much more in the long run by cutting down your monthly bills.

How many more years do you plan to use your equipment? If you intend to relocate and sell your house in the near future, installing a new top-of-the-line HVAC may not be in your best interest. It might be better to replace individual defective components instead. Speaking to local realtors will give you a good idea of what buyers are looking for and you can plan accordingly.


Where Can I Find a Trustworthy and Qualified HVAC Installation Expert in My Area?

Young woman in winter attire pointing technician to a radiator on the wall.Do some online window shopping and compare different companies around your location. A local company will be familiar with the area and its climate and will be better placed to offer good advice and knowledgeable service. Take a look at Yelp and Facebook reviews; see what past clients have to say. When asking for quotes from different installers, make sure they are for the same system and cover the same scope of work.


Which Unit Is Best for Me?

Check the web for information about the standard size of HVAC for your location and home size, to get an initial idea of what you will need. Installing a unit that’s too big for your home will be just as bad as installing one that’s too small. Both of these will result in irregular levels of heating and cooling in your living space, and higher energy bills. Then discuss with your HVAC technician about their recommendations on the best units for your home. If you feel uncertain, get a second opinion.


Are Certain Times of the Year Better to Shop for HVAC Systems?

This image is a panel showing a tree in spring, summer, fall, and winter.Since the Virginia-Maryland area experiences extreme weather during the winter and summer, you may want to wait until more moderate months to replace an HVAC system, furnace, or AC. Demand for these systems will also be less in the temperate months, so you might get faster service and maybe even better prices. In the meantime, see if you can do repairs to tide you over.

However, this is not a hard and fast rule. If the repairs are major and very costly, and your unit is just not working well, then by all means, find an HVAC contractor you trust who can replace your old unit quickly.


How Much Will It Cost?

The cost of replacing a whole HVAC system, AC or furnace will greatly depend on the brand and grade of the system you choose, and the area it will cover. You will also need to factor in any related costs such as ductwork, air purifiers, humidifiers and/or dehumidifiers, and a thermostat, as well as labor. Taking all of these into account, as of 2020, the average cost for a new HVAC unit without ductwork runs from $4820 – $9350, and with ductwork $6820 – $12,350.

Air conditioning units are rated by SEER scores (Seasonal Energy Efficiency Ratio), and refer to a unit’s maximum efficiency level. The higher the SEER score, the more efficient it will be, although the initial outlay may be bigger. Talk to a qualified local HVAC company about minimum required SEER ratings in your area.

When you contract for a bid, always ensure that the technician coming to your home has access to all areas – including crawl spaces, attics, and basements – so that you receive an accurate quote. Also make sure all costs are included in the quote and ask for a breakdown of expenses: equipment, labor, removal of existing equipment, refrigerant, any other parts, electrical work, code compliance, and any extras.


What Is the Right Size of Air Conditioner for My Home?

AC units can be measured by either tonnage or cooling power. The larger the tonnage, the more power it will have. If you have a small house, it will be more efficient to purchase a 1-ton unit rather than a 5-ton one. There are several factors that determine what the best size unit is for your home:

  • The area of the space
  • The location of your home and the local weather and climate
  • The current insulation in your home, including doors, windows, and in the walls and roof.




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DM Select Services is a long-time, family-run HVAC company serving N. Virginia, Maryland, and Washington D.C. Our team of qualified and experienced HVAC technicians can help with any of your heating, cooling, and ventilation needs, from the smallest job to installing a full system. Contact us today and we’ll help you figure out the best system for your home or workplace. For fast and reliable HVAC services, call (703) 721-4844 or request a free quote online.