All modern HVAC systems require electrical access. While heat pumps, air conditioners, and electric heaters clearly run on mains power, even oil and gas furnaces require power for their igniters and control circuitry. Problems with your home's electrical system or inadequate service can affect your HVAC system and lead to issues.

If you're installing a new HVAC system, now is the perfect time to address these issues and ensure your home's electrical service can provide enough power to run your HVAC system. This guide will help explain how upgrades work and why you may need one when installing new HVAC equipment.

What Are Electrical Service Upgrades?

Your main electric service panel determines the power available for devices in your home. You can think of the service panel as a "budget" for each circuit. For example, if your home has 200A service, the total of all circuits in your home will need to be 200A or less. Most circuits in a home will use 15A or 20A breakers, with dedicated circuits for larger appliances requiring more.

Most modern homes use 100A or 200A service, although 400A may be commonplace on larger homes, and some older houses may only have 50A service. Surprisingly, HVAC equipment is one of the primary drivers behind higher amperage service panels in newer homes. For example, four or five-ton air conditioning units may require dedicated circuits with 35A or 40A breakers.

Note that upgrading your home's electrical service isn't simply a matter of contacting your electrical company. Instead, you'll need an electrician to upgrade your existing service or install a new one.

Should You Upgrade for a New HVAC System?

Several factors will likely determine whether your need an upgraded electrical service panel for your new HVAC installation:

  • Is your new unit larger than your old one?
  • Did your old unit frequently trip breakers or cause other electrical problems?
  • Are you installing an AC in a home that previously did not have one?
  • Have you recently renovated your home or added other large electrical appliances?

In general, you may need to upgrade your service panel if the dedicated circuit for your new HVAC equipment exceeds the capabilities of your current service panel. This situation typically arises when upgrading to a larger unit or adding a central air conditioning system to a home that previously did not include one.

Older homes are the most likely to require service panel upgrades. For example, you'll probably need to upgrade if you live in a home that still uses 50A or 100A service, especially if you're installing a relatively large AC unit. You may also need to upgrade if you've added extra electrical loads through renovations in the years since your previous install.

As with any other aspect of your home's electrical system, it's best to consult with an electrician before deciding on a service panel upgrade.