For years, furnaces have been the go-to heating system in Maryland homes. But as energy costs rise and homeowners become more focused on comfort, efficiency, and sustainability, heat pumps have emerged as a smarter, more effective solution. If your goal is a more comfortable home—without hot and cold spots, high fuel bills, or noisy on/off cycles—this guide will help you understand why multi-stage and variable speed heat pumps are worth considering.
In this article, we’ll walk through how furnaces and heat pumps work, compare their comfort performance, energy use, and operating costs, and explain the important considerations before making the switch. We’ll also break down how system sizing, duct design, and insulation play a critical role in comfort and efficiency.
Traditional furnaces generate heat by burning natural gas, propane, or oil. That combustion heats a metal heat exchanger, and a fan pushes air across it, delivering warm air through the duct system. Furnaces typically supply air between 120°F and 140°F. They’re usually sized to meet the coldest outdoor temperatures, which can lead to oversizing—meaning the furnace cycles on and off frequently, reducing comfort and efficiency.
Unlike furnaces, heat pumps move heat instead of generating it. In heating mode, they extract heat from the outdoor air—even in winter—and transfer it indoors using a refrigeration cycle. In cooling mode, the process reverses. Heat pumps generally supply air at lower temperatures than furnaces—between 90°F and 105°F—which feels different but still keeps homes comfortable when the system is designed and sized properly.
Not all heat pumps are created equal. Single-stage units operate at full power or not at all, which often results in short cycling, uneven temperatures, and reliance on expensive backup heat. Multi-stage and variable speed heat pumps can adjust their output based on the outdoor temperature and the heating demand. That means they run longer at lower speeds, maintaining more consistent temperatures and better humidity control—especially in Maryland’s mixed climate.
If you're used to the high blast of hot air from a furnace, the lower supply temperature from a heat pump can feel cooler by comparison. But that doesn’t mean the system isn’t heating effectively. In fact, longer run times on multi-stage and variable-speed heat pumps help circulate air more evenly, which often leads to better overall comfort and fewer hot or cold spots.
Heat pumps can extract heat even in very cold temperatures. Variable speed systems are particularly good at this—they can maintain indoor comfort even when it’s 5°F outside without switching to auxiliary heat. In Maryland, temperatures rarely fall below that, meaning a properly sized, variable speed heat pump can handle nearly every winter day on its own.
Heat pumps use the same compressor for both heating and cooling, which means they must be sized carefully. In Maryland, heating loads are typically 30% higher than cooling loads. Oversizing a single-stage heat pump for heating can cause cooling issues in summer, like poor humidity control and short cycling. That’s why variable speed systems are ideal—they can scale up or down as needed for either season.
|
Feature |
Furnace |
Heat Pump |
|
Supply Air Temperature |
120-140°F |
90-105°F |
|
Sizing Considerations |
Often oversized without major drawbacks |
Must use multi-stage to avoid relying on auxiliary heat |
|
Safety |
Risk of gas leaks or carbon monoxide |
Generally safer; no combustion |
|
Energy Costs |
Dependent on fuel prices |
High-efficiency models often cost less to run than gas or oil |
|
Comfort |
Prone to uneven temperatures and short cycling |
More even temperatures and better humidity control |
The Inflation Reduction Act offers federal tax credits of up to $2,000 for installing high-efficiency heat pumps.
Maryland electric utilities offer $750 to $2,000+ in rebates for heat pump installations. The final amount depends on how much energy the new system saves compared to your old one. To qualify, you’ll need a home energy audit and must complete some additional energy-saving upgrades, such as insulation or duct sealing. Potomac Edison, BGE, Pepco.
Switching from high-efficiency gas to electric may not offer immediate savings but could in the long run as fuel prices shift. If you currently use propane or oil, a heat pump upgrade is almost always cost-effective.
HVAC systems are 10- to 15-year investments. If you’re replacing your system soon, it’s worth considering what energy costs will look like in the coming years.
A Manual J load calculation is critical. It ensures your new system is the right size. You’ll also want to evaluate your ductwork to ensure it can handle the airflow requirements of a heat pump.
Heating and cooling systems can’t perform well if the building envelope isn’t doing its job. Before replacing your HVAC system, it’s smart to improve insulation, air sealing, and duct sealing.
Adding insulation in key areas—like attics, crawlspaces, and garage ceilings—reduces demand on your system. Air sealing keeps that conditioned air from escaping.
Leaky ducts can waste up to 30% of the air your system produces. Sealing them (especially with a technology like Aeroseal) is one of the best ways to boost comfort and efficiency.
Start with a home energy audit. It will show where your home is losing energy, qualify you for rebates, and help you make smarter decisions about your HVAC system. Whether you choose a heat pump or another solution, we’ll help you design a system that fits your home—and your comfort goals.
Atlas Home Energy
