Let me be blunt: if your building is cold because the thermostat is doing something strange, buying a space heater is not a heating solution. It's a delay tactic. And in the six years I've spent managing HVAC purchasing for a mid-sized company, delay tactics have cost us more than any faulty part ever did. The “temporary” space heater that looks like a bargain is often the most expensive line item on your monthly operating statement.
I've overseen roughly $180,000 in cumulative HVAC spend across two office buildings and a warehouse—thermostats, sensors, blower motors, service calls, and yes, an embarrassing number of portable heaters. The pattern I keep seeing is that we reach for a portable heater whenever a system behaves unpredictably, rather than asking why it's behaving unpredictably. Every time we've done that, we've eventually paid for the diagnostic anyway—plus the heater, plus the extra electricity.
The winter that made me question “temporary” heat
In late 2023, tenants in one of our satellite offices began complaining about cold drafts. Our maintenance tech checked the air handler, changed the filter, and confirmed there was warm air at the vent. Yet the room still didn't feel comfortable by mid-morning. The thermostat on the wall showed 68°F, but the far side of the office felt noticeably colder.
Rather than call a technician right away, the standard reflex kicked in. We purchased two Lasko heaters—about $95 each, if I remember correctly, plus tax—and placed one in each affected office. The immediate comfort complaint went away. The electric bill did not. Comparing the utility invoices, the extra consumption in that building was around $110 in December and $130 in January. The heaters were doing exactly what they were designed to do—converting electricity into heat. They just weren't addressing the reason the building's own heating system wasn't doing its job.
We finally called a technician in February. I should have called him in November. He found the problem within 20 minutes: an outdoor reset sensor mounted on the north side was feeding inaccurate resistance readings back to the thermostat. The thermostat thought the outdoor temperature was around 50°F when it was actually 22°F, so it was ending the heating cycle far too early. The failed part was a Honeywell outdoor temperature sensor—the same style originally spec'd for our unit.
The replacement—a Honeywell E52-P20AY-1 temperature sensor, if I'm reading the invoice line correctly—cost about $50 at the local supply house. The service call ran a few hundred dollars. So the real fix was, maybe, $350 total. Meanwhile, the “temporary” heaters had already cost us roughly $240 in extra electricity in two months, plus their own purchase price, plus the continued tenant discomfort. The heaters didn't fail. They just couldn't fix the thing that mattered.
Why I almost approved a $950 blower motor job that wasn't needed
A second example, and the one that permanently changed my review process: In Q2 2024, one of our warehouse air handlers started moving noticeably less air. The vents were hissing instead of pushing. Our regular vendor ran an amp draw test on the blower motor and found it drawing below spec. Their recommendation: replace the blower motor—$950 including parts and labor.
The data supported that call. My gut didn't. I remembered a similar “component failure” two years earlier that turned out to be a control issue, and I still felt the sting from that invoice. So I asked for a senior tech to review the system before we authorized anything. He traced the low amp draw to a fan speed control that had been bumped down, likely during a filter change. The blower motor was fine. A setpoint adjustment restored the airflow in about ten minutes.
That experience reinforced something I already suspected: individual component failures are often the product of upstream control issues. A blower motor doesn't usually die because it's a bad motor. It dies because something keeps making it run when it shouldn't, or at the wrong speed, or with poor airflow. Replacing the motor without diagnosing the control chain is how you end up paying for the same repair twice.
This is why I now treat a space heater purchase the same way I treat a blower motor replacement quote. If it's a response to a recurring system problem, I ask for the diagnostic first. A portable heater might keep people comfortable for an afternoon. It won't keep the fan speed from getting knocked off, or the outdoor sensor from drifting, or the thermostat from short-cycling.
The free fix that belongs in every TCO checklist
Before you buy any part, before you schedule any service call, try the cheapest move in the book: reset the thermostat. I know “how to reset thermostat” sounds too simple to matter, but a lot of momentary control glitches clear with a full power cycle. On most commercial Honeywell thermostats, the procedure is:
Switch the system to Off. Wait about 60 seconds (or remove the faceplate/batteries if your model requires a harder reset). Switch it back to Heat and set your desired temperature. Let the system run through at least one full cycle.
We have prevented at least two service calls this winter alone just by doing this before phoning anyone. It doesn't fix every issue—a degraded outdoor sensor or a failing limit switch needs actual replacement. But when it works, it costs literally nothing. And when it doesn't work, you've at least ruled out one variable for the technician.
I'll add the obvious caveat: I'm not anti-portable-heater in every context. If you need spot heat on a loading dock or in a workshop bay, a portable unit is a legitimate tool—and I've typed “lasko heater” into more than one shopping cart myself when the warehouse got cold. But when you're using it to keep an occupied office tolerable because the heating controls are misbehaving, you've turned a $50 component problem into a monthly operating expense. The underlying problem is still waiting for you.
The TCO approach that changed how I buy
From the outside, a $100 space heater looks cheaper than a $350 service call. What that view misses is the second invoice that always follows—the electricity, the repeated complaints, the eventual diagnostic, and sometimes a new blower motor if the neglect goes on long enough. I'll take the diagnosis-first route every time.
Here's my current policy after reviewing six years of HVAC invoices: any time someone in our company asks for a portable heater to fix a recurring temperature complaint, we pair that request with a diagnostic visit. The heater can come—it just can't be a substitute for finding out why the system isn't doing its job. In the cases where we followed that process, our total cost ended up three to four times lower than the cases where we let the heater silence the complaint until the real problem got more expensive.
I'd rather spend $350 on a service call and a Honeywell sensor than $240 in extra electricity plus $200 in space heaters and still face the same thermostat issue in March. That's not a judgment call about portable heaters as products. It's a judgment call about treating symptoms instead of causes. Six years of spreadsheets say the causes are where the savings are hiding.
