How Heat Pumps Have Evolved Over the Years

Written by Butch Garey – Founder of 1st Service Heating and Air.

Heat pumps have been around for decades, and I’ve personally seen the evolution firsthand after more than 45 years in the HVAC industry.

Back in the late 1970s and 1980s, heat pumps started becoming more common in homes. Many of those early systems were large, inefficient, and built with older technology. Units like the Williamson systems were bulky outdoor units connected to large indoor furnaces, and brands like Janitrol (now known as Goodman/Amana) offered more budget-friendly options.

These older systems were typically single-speed, meaning they ran at full power every time they turned on. That’s why many homeowners remember lights flickering when their system started—it was pulling maximum power all at once.

Why Older Heat Pumps Were Less Efficient

Older heat pumps had:

• One-speed operation (full power or off)
• Higher energy consumption
• Less humidity control
• Limited performance in cold weather

They also relied on relays, switches, and older mechanical components instead of today’s advanced control boards.

The New Generation of Variable Speed Heat Pumps

Modern systems have completely changed the game.

Today’s variable capacity heat pumps, like BOSCH IDS systems, can adjust their output based on your home’s needs in real time.

Instead of running at 100% all the time, they can:

• Ramp up on very hot or cold days
• Slow down during mild conditions
• Maintain more consistent indoor comfort

This means better efficiency, better comfort, and lower energy use.

Real-World Example of Energy Savings

Let’s say your home needs 3 tons (36,000 BTUs) of cooling on a very hot day.

With an older system → it runs at full capacity every time.

With a variable system → it may only run at:

• 2.5 tons
• 2 tons
• or even lower

That means you’re only using the energy you actually need.

This also improves humidity removal, making your home feel cooler and more comfortable.

Simple Way to Understand the Difference

Think of it like cooking on a stove.

You wouldn’t turn every burner on full blast just to heat one pan.

Old systems = full power all the time
New systems = adjust to exactly what’s needed

That’s the difference between outdated and modern HVAC technology.

Are Variable Speed Systems Worth It?

Yes—they cost more upfront, but they deliver:

• Lower utility bills (we’ve seen bills cut significantly)
• Quieter operation
• Better humidity control
• Longer system lifespan
• Improved comfort year-round

Instead of overpaying your utility company every month, you’re investing in efficiency and comfort.

Get a Free Heat Pump Estimate in Richmond, KY

If your system is older, it may be costing you more than you realize.

At 1st Service Heating & Air, we help homeowners across Richmond, Lexington, and surrounding areas upgrade to high-efficiency systems that save money and improve comfort.

Call (859) 333-5191 today
Request your free, no-obligation estimate
Ask about financing options with low monthly payments