TOPGREENER Circulator Switch, Hourly Fresh Air Timer for Ceiling and Wall Ventilation Fan and Bathroom Fan, Countdown Time Delay, LED Indicator, 120VAC, 1/4HP Motor, 3A Max Fan Load, TDTS5-W, White

Why I tried this timer switch

I wanted a simple, set‑and‑forget way to keep air moving in a couple of problem spots in my house: a windowless bathroom that loves to grow condensation, and a basement office that gets stuffy by mid‑afternoon. I wasn’t looking for a humidity sensor or a smart switch—I just wanted a reliable schedule that would run a fan for a short period each hour and a way to run the fan after showers without someone forgetting to turn it back off. The Topgreener timer switch hit that brief, and after living with it, I’m glad I chose the straightforward approach.

What it is and how it works

At its core, this is an hourly fresh‑air timer for a 120V, single‑pole ventilation fan circuit. You set how many minutes per hour the fan should run—anywhere from 5 to 60 minutes—or turn the feature off entirely. There’s also a manual ON/OFF switch to override the schedule. An LED illuminates whenever the fan is running, and it briefly flashes when you change settings so you know your adjustment “took.”

It’s UL‑listed and rated for up to a 1/4 HP (3A) motor load, which covers the vast majority of bathroom and in‑ceiling ventilation fans. It requires a neutral wire to power the electronics (typical in newer homes) and installs like a standard single‑pole switch.

Installation: smooth if your box is ready

Wiring it was straightforward: hot (line), switched hot (load), neutral, and ground. Two things to know before you start:

• You must have a neutral present in the switch box. If your house is older and only has line and load, this isn’t the right product unless you run new cable.
• The body is bulkier than a simple toggle switch. A standard‑depth box can work, but a deeper box makes life easier, especially if you already have a few wirenuts in there.

On one bath, I had a deep box with an accessible neutral; installation took ten minutes. In the basement, space was tighter; I had to take a little extra time folding wires neatly to seat the device. I appreciated that the ground connection is a screw on the device rather than a flying lead—it kept the wire count down in a crowded box. The wall plate isn’t included, so you’ll need a Decora‑style plate to finish the install.

The “minutes per hour” adjustment is a small knob hidden behind the faceplate. I like that decision: it keeps the setting accessible without inviting casual tampering. A small flathead screwdriver is all you need to set it.

If you’re not comfortable identifying line vs. load or confirming neutral, bring in an electrician. As with any timer switch, miswiring can lead to frustration (or a non‑functional fan).

Daily use and performance

In the bathroom, I set the schedule to 30 minutes per hour and taught my family to hit the manual ON before showering. The switch runs the fan and then shuts it off automatically on the timer, which has all but eliminated the “fan left on all day” issue. More importantly, the mirror clears faster post‑shower, and the room doesn’t smell musty at night.

In the basement office, 15 minutes per hour made a noticeable difference in how the room feels by late afternoon. I leave a nearby door cracked, and the gentle, predictable air exchange keeps the space from going stale without running a fan continuously.

Noise is, of course, a function of the fan, not the switch. But by carving the hour into short run segments, the switch lets you move air without the constant drone you get from continuous run setups. If you’re sensitive to nighttime noise, you may want to set a shorter interval in bedrooms or skip hourly cycling there and use the manual mode only.

I found the LED implementation just right: it lights only when the fan is on, and it’s not distractingly bright in a dark room. The brief flash when you change the timing is a helpful confirmation that you didn’t miss a detent on the dial.

After several months of daily cycling, it’s been stable—no missed cycles, no drifting settings, no odd behavior. The manual override behaves predictably, and the hourly schedule resumes after an override ends.

What it does well

• Keeps air fresher in windowless or low‑ventilation rooms without running a fan all the time.
• Prevents fans from being left on indefinitely; the manual run auto‑shuts off on the selected timer.
• Simple, physical controls; no app, no cloud, no calibration quirks.
• LED feedback is useful without lighting up the room.
• UL‑listed, and the 3A/1/4 HP rating suits most residential ventilation fans.

Where it comes up short

• Neutral required. If your switch box doesn’t have one, this isn’t a drop‑in solution.
• The device body is chunky; tight boxes can be a squeeze.
• Single‑pole only. If your fan is controlled from two locations, this won’t replace a 3‑way circuit.
• It’s not a humidistat. It won’t detect spikes in humidity and react automatically; you have to set minutes per hour and use manual mode after showers.
• No time‑of‑day schedule. If you want the fan to run more during the day and less at night, you’ll be adjusting the dial seasonally or leaving it to the manual override.

None of these are deal‑breakers for what this is designed to do, but they’re worth considering for your use case.

Setup tips from the field

• Check the fan’s amperage draw. Most bathroom fans are well under 3A, but verify the nameplate to stay within the 1/4 HP rating.
• Confirm a neutral in the switch box before buying. Look for a bundled white conductor tied into other neutrals—not just a white wire on the switch (which could be a re‑purposed hot in older wiring).
• Plan for box fill. If you have multiple switches in a single gang box, you may need a deeper retrofit box to keep things tidy.
• Label your setting. I put a tiny piece of tape inside the faceplate noting the chosen minutes per hour; it’s handy months later when you forget whether you left it at 15 or 30.
• Pair with a quiet, efficient fan. The best schedule won’t help much if the fan can’t move air or is so loud you avoid using it.

Who this is best for

• Bathrooms without windows where humidity and odor linger.
• Basements, laundry rooms, and small offices that benefit from regular air changes.
• Households with kids or guests who forget to turn fans off.
• Anyone who prefers a reliable, low‑tech solution over app‑driven controls.

If you need automated humidity detection, time‑of‑day scheduling, or smart‑home integration, this switch isn’t targeting that space. If you want a dependable, set‑once airflow routine, it’s a great fit.

Reliability and build

The face and buttons feel solid, and the electronics have been consistent. The hidden timing dial has positive detents, and the manual rocker switch has a clean click. Being UL‑listed inspires confidence, and the 120VAC, 60Hz spec is in line with typical residential setups. I also appreciate that the manufacturer separates the wall plate as an accessory; it’s easier to match plates across a room when they’re not forced on you.

Final take

The Topgreener timer switch strikes a smart balance: it automates just enough to solve common air quality annoyances without adding complexity. The hourly run feature makes a real difference in rooms that otherwise get stale, and the manual countdown neatly handles post‑shower ventilation without wasting energy. Installation is approachable if you have a neutral and a bit of box space, and once it’s in, you can mostly forget it’s there—exactly what I want from a utility control.

Recommendation: I recommend this switch for anyone who wants a reliable, no‑nonsense way to keep air fresher in bathrooms, basements, and small closed rooms. It’s especially good in homes where fans get left on or not used long enough after showers. Skip it only if you don’t have a neutral in the box, require 3‑way control, or need smart/humidity‑sensing features.