The Big Mistake in My Garage
I'm a homeowner in Sioux City, Iowa, and a few years ago, I made a decision that, in hindsight, cost me a lot of time and money. I needed to heat my garage. I wanted to use it as a workshop in the winter, but it was always freezing. My first thought was a traditional HVAC system. But then I heard about heat pumps. They're efficient, right? They can both heat and cool. It sounded perfect.
So, I went out and bought a heat pump. A big one. I thought I was being smart. I thought I was getting the latest technology. I thought I was going to save a ton on my energy bills. Instead, I got a garage that was barely warm enough, a confusing thermostat, and a big headache. This is the story of that mistake, and what I learned about Daikin, thermostats, and why a heat pump isn't always the best answer.
In short, I learned that the promise of a heat pump doesn't always match the reality of a Sioux City winter. I'm not an HVAC engineer, so I can't speak to the thermodynamics of every model. What I can tell you from my own personal experience is that choosing a system requires more than just looking at an efficiency rating.
What I Thought Was the Problem (And What Actually Was)
When the heat pump first went in, I was hopeful. The installer—a local guy, not a Daikin specialist—set it up. He connected it to a basic thermostat. Within a few days, I noticed the problem. The air coming out of the vents wasn't hot. It was lukewarm. It was like trying to warm a room with a hair dryer on a low setting.
My first thought was that the unit was broken. Or maybe I'd bought the wrong size. I spent a lot of time online, searching "daikin heat pump not heating" and "heat pump vs hvac for garage." I kept hitting dead ends.
The real problem was more subtle. It wasn't the heat pump's ability to heat. It was the combination of a few things: the outdoor temperature, the insulation of my garage, and—this is the big one—the thermostat setup. I'd read all the brochures about how efficient a Daikin heat pump is. The literature says stuff like, "Daikin inverter technology allows for precise temperature control." That's true, in a lab. In my garage, with a poorly matched thermostat, it was a mess.
Take this with a grain of salt, but I believe the issue came down to the defrost cycle. In cold weather, heat pumps have to periodically reverse their cycle to defrost the outdoor unit. During that time, the indoor unit often blows cool air. On a Daikin system, the thermostat is supposed to manage this cycle to minimize that cool air. But the thermostat I had—a basic model—didn't do this well. Every 20 minutes or so, the garage would get a blast of cold air. The room never truly felt warm.
The Cost of the Mistake
The real cost wasn't just the price of the unit. I bought the Daikin heat pump for about $1,800. I also paid $600 for installation. Then there was the thermostat. I tried three different models before I figured out the problem.
- First thermostat (cheap): $40. Didn't work.
- Second thermostat (mid-range): $120. Still had the cold air problem.
- Third one: Daikin's own connected thermostat. $350.
I spent over $500 on thermostats alone. That's $500 that I wouldn't have spent if I'd just gone with a standard furnace in the first place. I'm not 100% sure, but I think the total cost of my experiment was close to $3,000. For a garage heater.
In March 2024, I finally gave up. I disconnected the heat pump. I bought a simple 5,000-watt electric garage heater—a shark fan style unit—for $150. It plugs in, I flip a switch, and it blasts hot air. It's not as efficient as a heat pump, but it works. The garage is warm. And I'm not fighting with a thermostat.
What I Learned About Daikin Thermostats
This gets into technical territory, which isn't my expertise. I'd recommend consulting a proper HVAC contractor. But from my perspective, here's the key takeaway:
Daikin thermostats are not all the same. The Daikin One+ is a great thermostat, but it's designed to work with their ducted systems and their specific communicating protocol. If you're a DIY guy or a general contractor who slaps on any old thermostat, you're likely to have the same issues I did. The Daikin system seems to really need its own thermostat to manage the defrost cycle correctly. I've only worked with residential heat pumps. I can't speak to how this applies to their larger commercial HVAC systems.
The Real Solution: Knowing When to Pay for Simplicity
Looking back, I was chasing the wrong metric. I thought energy efficiency (SEER2, HSPF) was the most important thing. For my specific need—heating a single, poorly insulated garage in Sioux City—simplicity and reliability were far more important. I should have budgeted for the simplest, most reliable solution, not the most technologically advanced one.
Personally, I'd argue that for a garage, a simple electric heater or a gas-fired unit heater is a better choice than a heat pump. The heat pump's complexity (the reversing valve, the defrost cycle, the refrigerant lines) creates too many points of failure and confusion for a space that doesn't need perfect, even temperature control.
Here's my rule now: For a primary living space, a Daikin heat pump with the proper thermostat is a great choice. For a workshop or garage where I just need to take the edge off, I'm going with the simplest, dumbest, most reliable heater I can find. It's about time certainty. I want to know that when I flip the switch on a cold January morning, the heat is going to run. No defrost cycles. No confusing thermostat programming. Just heat. And that's worth the premium on my energy bill.
