Your HVAC system should keep you warm in the winter and cool in the summer. If it is not doing that, there is something wrong with it. Either the furnace is broken, or the air conditioner is. You may be tempted to replace only the damaged unit when this happens, but beware! It's not a good idea to combine an old A/C with a new furnace or vice versa. Doing so could reduce efficiency and performance. There are several reasons why you should replace the two together even if only one is broken. Read on to find out why.

Advantage: Having a Properly Matched System Increases Longevity and Efficiency

If malfunctioning, it’s likely your HVAC system is outdated. Replacing only one part would mean mixing an efficient device with an old, inefficient one. The technology for HVAC systems has improved and developed significantly over the years. All new systems have a minimum Seasonal Energy Efficiency Ratio (SEER) of 13. This means a new unit with minimum efficiency is still more efficient than one bought even as recently as five years ago.

Replacing both parts of the unit will offer you better efficiency and performance. You can also reap the full benefits of the new technology that comes with new units. One significant benefit is that you’ll likely have lower utility bills.

If you replace the two units together, you don't need to worry about replacing the second part a few months or years later. If you replace only one at a time, you may have trouble when it’s time for repairs. The process could end up being very complex and quite expensive if you’ve mixed an old and new unit.

Using matched systems also promotes efficiency and the entire system's smooth operation. The furnace and air conditioning unit share the same air handler, and using mismatched products may cause efficiency problems. 

You also ultimately save money when you replace the two units together. You will not need to worry about paying for air conditioning or furnace repair work, as the new unit will be covered by a warranty. Also, some manufacturers will not honor the warranty for new products that have been combined with old products. 

Advantage: Mixing Old and New Systems Can Decrease Performance

Mixing new and old units may not be good for the new unit. The unit might not work at its full potential since the components may have a hard time functioning together. As a result, you may lose out on energy cost savings, and your new unit may also develop problems due to incompatibility.

Disadvantage: Cost

A new furnace costs between $2600 and $4600, while a new air conditioning unit costs between $3800 and $7500. That is a hefty amount if you need to replace your units out of the blue. Although replacing both units may be expensive, it will save you money in the long run.

The only time it is not prudent to replace them together is when you already have a new and matched combination of heating and air conditioning units. In such situations, it would be reasonable to replace only the faulty unit, since the same model will likely be available on the market.

Get in Touch With Us

Need help with your home's HVAC system? We can help. Heat Mechanical Heating and Cooling offer full service for your property heating and cooling needs. We are a one-stop shop for all your furnace and AC installation needs. Our team of professionals is honest and skilled and will stop at nothing to satisfy our customers.

Call us at 972-937-0697 or complete this form to get in touch with us.