Start with the zones, not the catalog

For most small and mid-size offices, you should buy three or four right-sized units instead of one whole-building HVAC overhaul. In our 120-person office, the fix wasn't a new rooftop unit. It was a Dimplex oil radiator for two drafty perimeter offices, a bathroom exhaust fan for the damp restroom, a dehumidifier for the basement archive, and a Frigidaire ice maker for the breakroom. The total was less than a single emergency service call during peak summer. That's the conclusion. Now the why.

I'm the office administrator for a 120-person company. I manage facilities and service ordering—roughly $85,000 annually across 12 vendors. I report to both operations and finance. I took over purchasing in 2020, and I've processed 60-80 orders a year since. My experience is mostly mid-size commercial offices and two satellite sites. If you're outfitting a warehouse, restaurant kitchen, or retail floor, your needs will differ.

What I'd buy first for supplemental heat

For a quiet office where people sit for hours, I'd start with a Dimplex oil radiator. It's not instant. It doesn't blow hot air in your face. But it holds heat steady, doesn't dry out the air as much as fan-forced ceramic heaters, and it's silent enough for a phone call. We put one in a 12x14 corner office that never got warm after 3 p.m. The occupant stopped bringing in a personal space heater, which made our safety officer happy.

Even after choosing the Dimplex oil radiator, I kept second-guessing. What if it heated too slowly? Didn't relax until the first cold snap passed and the energy bill didn't spike. That's the thing about facilities purchases—you don't really know if you got it right until the season changes.

For outdoor break areas or a covered patio, the calculation changes. A Dimplex infrared patio heater heats people and objects, not the air, so it works better in open or drafty spaces. We used one for a smoking area and a lunch patio. It doesn't replace a building heating system, but it extends outdoor use by a few weeks in spring and fall. (Thankfully, no more complaints about cold breaks in October.)

I still kick myself for not checking the plug load earlier. We had two 1,500-watt heaters on one circuit. The breaker tripped during a client visit. Now I map circuits before I place any heater order. If you're buying for a small office, ask facilities for a circuit map—or hire an electrician to check. That's not optional.

Ventilation: the bathroom exhaust fan is not a luxury

The least glamorous purchase on this list is the one that prevents the biggest long-term problem: a properly sized bathroom exhaust fan. If moisture sits on drywall, mirrors, and metal fixtures, you get mold, peeling paint, and rust. In 2022, we ignored a weak fan in a second-floor restroom. Six months later, we paid $1,800 to repair ceiling paint and replace a light fixture. The fan itself would have cost a fraction of that.

For commercial restrooms, check CFM rating, sones (noise), and duct length. A fan that's too small won't clear steam. A fan that's too loud won't get used. We now specify fans with a humidistat or timer so they run long enough after people leave. (Ugh, the number of times I found a manual fan switched off after 30 seconds.)

And don't confuse air movement with moisture removal. A ceiling fan or a tower fan doesn't exhaust humid air. It just moves it around.

Humidifier vs dehumidifier: get the direction right

The humidifier vs dehumidifier question comes up every winter. They solve opposite problems. A humidifier adds moisture to dry air. A dehumidifier removes moisture from damp air. If your office has static shocks, cracking wood furniture, and dry sinuses, you may need a humidifier. If you have foggy windows, musty smells, or a damp basement archive, you need a dehumidifier.

We bought a dehumidifier for a below-grade storage room after a pipe leak. The first unit was undersized. It ran constantly and never got below 60% relative humidity. I regret not measuring the room and checking the AHAM capacity rating. The second unit—sized for the square footage and the dampness level—held the room at 50% and cycled normally. That's when I finally relaxed.

When comparing dehumidifiers, use the AHAM capacity rating and Energy Star listing, not just the pint number on the box. As of January 2025, those are the two specs I check first.

For Dimplex specifically, their dehumidifier line fits the same logic as their heaters: programmable controls, auto-restart, and low-wattage options. They're not the cheapest. They're also not the most complex. For a facilities manager who needs predictable operation and a serviceable unit, that's usually the right trade-off.

Cooling and breakroom: don't overbuy the ice maker

On the cooling side, we use portable cooling fans and a small chiller for a server closet. But the keyword that keeps showing up in our purchasing requests is Frigidaire ice maker. For a 120-person office, a freestanding ice maker in the breakroom made more sense than adding a second refrigerator. We checked drain access, water line, and clearance before ordering. The first model we looked at needed a floor drain. Ours didn't have one. That would have been a $2,000 mistake.

My rule now: for any appliance with water, confirm three things before you buy—water supply, drain path, and ventilation clearance. If you can't check all three, don't hit confirm. I approved a water-cooled chiller once without confirming make-up water. The install crew had to run a new line. Finance asked why the project was 18% over budget. I didn't have a good answer.

Small orders are still worth doing right

I've managed $200 orders and $20,000 orders. The vendors who treated the $200 order seriously are the ones I still call for the big ones. Small doesn't mean unimportant—it means potential. If you're buying one Dimplex oil radiator for a reception area, you should still get a real quote, a real lead time, and a real invoice. If a supplier won't provide that, walk away.

That said, I can't promise every small order gets the same pricing as a bulk contract. It usually doesn't. What I can promise is that good suppliers don't punish you for starting small. They document the order, ship what they quoted, and answer the phone when something goes wrong.

What I'd do differently, and what still doesn't apply to me

I still kick myself for not documenting a verbal promise on a late heater delivery. The sales rep said it'll ship Friday. It shipped the following Wednesday. We had no written confirmation, so we ate the overtime for a temporary rental. Now I get lead times in writing, even on small orders.

My experience is based on 60-80 orders a year across mid-size commercial offices. I can't speak to heavy industrial refrigeration, clean rooms, or medical facilities. If you're working with those environments, your codes, redundancy requirements, and maintenance contracts will be different. Also, I'm not an electrician or HVAC engineer. I'm the person who has to make the purchase order work. For final sizing, circuit load, and code compliance, get a licensed professional.

If you only take one thing from this: match the product to the zone, not to the catalog. A Dimplex oil radiator for a drafty office, a Dimplex infrared patio heater for outdoor breaks, a bathroom exhaust fan for moisture, a correctly sized dehumidifier for damp storage, and a Frigidaire ice maker for the breakroom will outperform one oversized, overcomplicated system that nobody understands.