I've been the office administrator at our company since March 2020. That means I manage facilities purchases for about 340 people across three locations—roughly $150,000 in orders a year, depending on how many fit-outs and repairs we're doing. When the first cold-weather complaint lands in my inbox, I'm the one who buys the heaters.

This checklist is for anyone who handles heating for an office, warehouse, or small commercial space. It's not an engineer's guide. I'm not an engineer, and after five years in this role, I've learned that being honest about where my expertise ends is exactly why our vendors keep working with us. What follows is the routine I run before ordering a single unit.

Step 1: Walk through the cold space before you buy anything

The first winter I managed purchasing, I ordered two space heaters for a meeting room without looking at the room itself. The room measured 55°F at 9:00 a.m. It wasn't because the building lacked heat—it was because someone had closed the supply vent during a painting project the week before. No heater was needed.

Now I do a short walk-through before opening a purchase order:

  • Room size and ceiling height. A 1,500-watt plug-in heater is a spot solution, not a whole-building solution.
  • Exterior walls and windows. That's where the real heat loss is, and it changes which product makes sense.
  • Blocked vents or thermostats. File cabinets and fabric partitions hide more climate problems than equipment failures do.
  • Who is actually in the room. A room full of computers and monitors may need far less heating than a bare conference room.

This step takes 15 minutes. It has saved me more money than any vendor discount I've negotiated.

Step 2: Match the heater type to the room's job

This sounds obvious, but in my opinion it's the most common mistake people make: they pick one heating technology and try to apply it everywhere.

For occupied offices and meeting rooms, a Dimplex electric radiator is my default. It heats through natural convection and radiant output rather than a noisy fan, so it doesn't disrupt calls, and the unit-level controls are simple enough for employees to understand. We use them in areas where the central HVAC just can't keep up, and they've held up well.

For unoccupied spaces like storage rooms, electrical closets, or anywhere water pipes run along exterior walls, the job is different. You don't need to make that space comfortable—you need to keep it above freezing. That's where Dimplex tubular heaters with thermostat come in. They're low-wattage, they mount out of the way, and the thermostat keeps the space at a safe minimum without wasting energy trying to heat it to people temperature.

The same logic flips in summer. A Chillwell portable air cooler might take the edge off for one person in a small, dry office, but it's not a substitute for real cooling in a crowded room. Match the product to the actual problem, and you won't be as disappointed.

Step 3: Verify the electrical circuit can handle the load

This is the step most people ignore, and it's the one that made me look bad to my operations manager.

A 1,500-watt heater on a 120-volt circuit draws about 12.5 amps. If that circuit already feeds overhead lighting, a few computers, and a coffee maker, the breaker will trip. We learned this the hard way in 2022 when we put two electric radiators in a conference room. They worked individually. Together—and with the breakroom microwave on the same circuit—they didn't.

Before you order heaters in quantity, have maintenance or an electrician confirm what's actually available. If a room needs two heaters and there's only one circuit, you have an electrical project, not a heating product problem. I still kick myself for not checking this sooner, because the vendor's delivery arrived three days before we realized we couldn't run the units.

Step 4: Decide how the heat gets scheduled and controlled

Most modern electric heaters include basic controls, but controls matter more than people think. A heater without a thermostat runs at full power until someone remembers to switch it off. That's expensive and uncomfortable.

At the building level, we installed an ecobee thermostat for our main HVAC system in 2024. It handles the morning warm-up schedule and the evening set-back. That system serves the whole floor, and it's genuinely useful.

But here's the boundary I try to make clear to everyone in the office: the ecobee controls the central forced-air equipment. It does not control plug-in electric radiators. Each Dimplex radiator has its own built-in thermostat and programming, so I set those separately based on the room's use. If you assume one smart thermostat will manage every heat source in the building, you'll end up with rooms that are too hot or too cold and confused employees.

Know what controls what before you promise anyone a result.

Step 5: Compare long-term cost, not just the purchase price

In November 2022, I bought two budget fan heaters for a breakout area because they were about $70 cheaper than the radiator option. It felt like a small win until the first one failed in February and the second was so loud that nobody used it. By the next winter, I was ordering the Dimplex units anyway. The $70 I saved ended up costing us more than $300 in replacement equipment and a month of grumbling employees.

Now I compare based on what a heater will cost over its working life: purchase price, wattage, hours of use, and whether the thermostat can set back when the room is empty. I also read the claims with a skeptical eye. Per FTC advertising guidance (ftc.gov/business-guidance/advertising-marketing), claims like "energy-efficient" must be truthful and substantiated. If a vendor can't point to actual wattage and control features, I don't trust the marketing phrase. In my experience, the honest answer is usually in the product spec sheet, not the headline.

Step 6: Set safety rules before the heaters arrive

This is less about product selection and more about human behavior. If you manage an office, you already know that someone will do the thing you didn't plan for. In our case, an employee placed a heater under her desk to get it "out of the way." It wasn't a disaster, but the dust buildup on the unit produced a burning smell that triggered a small evacuation. The same heater in open space worked perfectly for two more years.

Our simple rules:

No heaters under desks. Period. They need airflow on all sides.

Plug directly into a wall outlet. Extension cords and power strips are not rated for continuous high-wattage loads in most cases.

Keep combustible material clear. A jacket hung over a heater "just to warm it up" is how fires start.

I don't love adding restrictions, but after five years, I've learned that a small set of clear placement rules prevents the same problems from recurring.

Step 7: Don't forget the places—and the food—nobody thinks about

The spaces that cause the most winter damage are the ones without desks. In January 2025, a hard freeze caught us with a storage room that had a water line running along an exterior wall. The room didn't need to be warm for people, but the pipe needed to stay above freezing. A Dimplex tubular heater with thermostat now runs in that room all winter, set to around 40°F. It costs very little to operate and gives us peace of mind.

The same hidden-damage principle applies to the breakroom freezer. Employees kept complaining that their frozen meals were developing ice crystals and white, dry spots—classic freezer burn. It wasn't because the freezer was too warm. Freezer burn happens when air reaches the food and pulls moisture out of it, even at 0°F. How to prevent freezer burn in an office freezer: check the door gasket for leaks, store food in airtight containers or heavy-duty freezer bags, and don't let frost build up inside. The fix cost us a $12 replacement gasket and a sign reminding people to seal their bags.

When you do your winter walk-through, open the doors you usually ignore: pipe chases, storage closets, the breakroom freezer. That's where January problems hide.

Mistakes I still see people make

If you take nothing else from this checklist, avoid these three:

Buying watts instead of control. A cheap high-wattage heater that runs all day costs more than a lower-wattage unit with a good thermostat that runs only when needed.

Oversizing the room. A 1,500-watt heater in a small office will cycle on and off constantly. It's not more comfortable; it just costs more.

Expecting one product to solve every problem. A product that claims to heat, cool, dehumidify, and replace your HVAC system is probably doing none of those things well. The vendors who say "this isn't what we're best at" are the ones I trust with the rest of the order.

That's the whole checklist. I still run it every fall, and it still catches something I would have missed.