Learn · Heating: Furnaces & Heat Pumps

Heat Pumps Explained for Central Texas

A heat pump heats and cools your home with a single system — and it does it by moving heat, not burning fuel. Our mild winters make Central Texas close to ideal heat-pump country. Here's how they work, what 'aux heat' means, and where they shine.

By Mike Dodge, Owner Updated June 17, 2026 7 min read

Reviewed by Mike Dodge, Owner of MLD Services (licensed TACLA37761C).

"Heat pump" confuses a lot of homeowners — it sounds like a heating-only device, but it actually does both heating and cooling with one outdoor unit. And here's the part that surprises people: it's one of the most efficient ways to heat a home in a mild climate like ours. If you're weighing your next system or just trying to understand the one you have, this is the plain-language version.

What a heat pump is

A heat pump is an all-in-one heating and cooling system that works by moving heat rather than creating it. It uses the same refrigerant cycle as your air conditioner — in fact, in cooling mode it is an air conditioner. The magic is that it can run that cycle in reverse to heat.

How it heats and cools with one system

Cooling (summer): It pulls heat out of your indoor air and releases it outside — exactly like a standard AC.
Heating (winter): A reversing valve flips the cycle. Now it pulls heat from the outside air (even cool air contains heat energy) and releases it inside.

Because it's relocating heat instead of burning fuel, a heat pump can deliver more heating energy than the electricity it uses — which is why it's so efficient in a moderate climate.

One system, both directions

Heat flow — out of the home in summer, into it in winter.
Same equipment — the reversing valve flips the direction.

A heat pump is an air conditioner that can run backward. In winter it pulls heat out of even chilly outdoor air and moves it inside — which is why heat pumps fit our mild Central Texas winters, with backup heat on the rare hard freeze.

Why Central Texas suits heat pumps

Heat pumps are happiest in mild winters — and ours qualify. We get relatively few hard freezes, so a heat pump spends most of the heating season in its efficient sweet spot. For all-electric homes especially, it can be the most cost-effective comfort system available. The trade-off arrives only on the coldest mornings, which is where backup heat comes in.

What "aux heat" actually means

When it's too cold outside for the heat pump to keep up, or while it briefly runs a defrost cycle, the system switches to auxiliary (emergency) heat — usually electric strips that cost more to run. Seeing "aux heat" on your thermostat during a hard freeze is completely normal. Seeing it run constantly in mild weather is a red flag worth a service call.

Where heat pumps fall short (the honest part)

On extreme-cold days, backup heat runs and your electric use climbs.
If you already have cheap natural gas and a good furnace, the math can favor keeping it.
An undersized or poorly installed heat pump struggles — install quality matters even more than the brand.

That's why we never give a one-size answer. The full side-by-side is in Heat Pump vs. AC + Furnace, and the basics of the gas alternative are in Gas Furnace Basics.

How MLD helps you decide

As a York Factory-Authorized dealer serving the Leander corridor since 2009, we install and service both heat pumps and gas systems — so we have no reason to push one over the other. We look at your home, your utility situation (many area homes are served by PEC), and your comfort goals, then recommend what actually fits, at a flat, written price. Education first, pressure never.

What to do next

Comparing system types? Read Heat Pump vs. AC + Furnace.
Heat not keeping up? See Heat Not Working? Troubleshooting.
Planning a new system? Get a free second opinion or request a flat-rate quote.

Call 512-528-4258 and we'll tell you honestly whether a heat pump fits your home.

Want a second opinion before you spend a dollar?

Send us another company's quote, or just ask a question. A licensed MLD Services pro will give you the honest, repair-first answer — with zero pressure.

Get a Free Second Opinion Call 512-528-4258

Quick Answers

Frequently asked

How does a heat pump heat without burning fuel?

A heat pump moves heat instead of making it. In summer it pulls heat out of your home (like a regular AC); in winter it runs the cycle in reverse, pulling heat from the outside air — yes, even cool air holds heat — and bringing it inside. Because it moves heat rather than burning fuel, it can deliver more heating energy than the electricity it consumes.

Do heat pumps work in Central Texas winters?

Very well. Our winters are mild, with relatively few hard freezes, which is close to ideal for a heat pump. Modern units heat efficiently across the temperatures we typically see. On the rare extreme-cold morning, the system uses backup 'auxiliary' heat to keep up.

What is 'aux heat' or 'emergency heat' on my thermostat?

Auxiliary heat is the backup (usually electric heat strips) a heat pump switches to when it's too cold outside to pull enough heat from the air, or briefly during a defrost cycle. Seeing 'aux heat' during a hard freeze is normal. Seeing it run constantly in mild weather is not — that points to a problem worth checking.

Is a heat pump right for my home?

It depends on your home, your existing equipment, and whether you have gas service. Heat pumps shine for all-electric homes and our mild climate, but a gas furnace can make sense too. We help you compare honestly — call 512-528-4258 or read our heat pump vs. furnace guide.

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