🔥 Hot Flanges & Fast Letdowns: Why Eufy’s HeatFlow™ Tech Might Just Change Your Pumping Life
Hey pumping parents — Jessica here! As your go-to IBCLC and certified pump nerd, I get to test a lot of pumping tech. But let’s talk about something truly exciting: Eufy’s HeatFlow™ Technology, featured in the Eufy S1 Pro — the only wearable breast pump with built-in flange warming.
Yes, you read that right. The flange. Heats. Up. đź‘€
Let’s dive into why that matters — and how it can help you get the most out of every pump session.
💡 What Is Eufy’s HeatFlow™ Technology?
HeatFlow™ is Eufy's term for their integrated flange-warming system. Unlike traditional silicone flanges that sit cold and lifeless on your breast (ugh), the S1 Pro has a thin heating strip built right into the upper rim of the flange, activated by little metal prongs. Think cozy, targeted warmth — not a toasty boob sauna.
👉 Take a look:
Here’s a thermal image of the Eufy S1 Pro with HeatFlow™ activated so you can see exactly where the warmth concentrates:
🔥 Why Add Heat at All?
Here’s the short version: warmth = flow.
Heat can:
Encourage faster milk letdown
Help empty the breast more efficiently
Potentially shorten your pump sessions
Turn a session from "supply sustainer" into "supply booster"
This isn’t a brand-new concept. Moms have been microwaving gel pads since forever (shoutout to Lano and Idaho Jones). But Eufy? Eufy took the concept and baked it in — no microwaving required.
🧩 Does It Work with Inserts?
One of the top questions I get is whether the heat still works when you're using inserts. Spoiler alert: yes — but only if the inserts don't cover the heating zone.
👉 Here’s what that looks like:
This thermal photo shows the HeatFlow™ element’s location in relation to Legendairy Milk inserts, which leave the heating rim completely exposed — perfect for maintaining warmth during use.
⚠️ Willow Go: A Warmed Flange, But Not On Purpose
Now, you might be wondering, “Don’t some other pumps get warm too?” Kind of — the Willow Go, for example, is known for running noticeably warm during use. But unlike Eufy’s HeatFlow™, it’s not intentional; it’s a byproduct of poor insulation and hot electronics.
👉 See the difference:
This thermal shot of the Willow Go shows how the warmth is more diffuse, uncontrolled, and inconsistent — making it a far less effective tool for milk expression compared to the deliberate engineering of the Eufy S1 Pro.
🎛️ Customizable Warmth (Because Not Everyone Likes to Feel Like a Hot Pocket)
One of the best parts? You can choose when and how much heat you want:
Two Modes: "Mild" (95–105°F) and "Hotter" (97–107°F)
Timer Settings: 5, 10, 15, or 20 minutes
User Favorites: Most parents love the 100–107°F sweet spot for better flow
Bonus tip: Too warm? Too tingly? Turn it down or off. You’re in control. And no, it won’t heat your milk — it’s concentrated only at the flange rim.
🧠Real Talk: Does It Actually Work?
For most clients I’ve worked with? Yes.
Examples range from cutting session times in half to better milk output and more productive second letdowns — all without changing anything else about their pumping routine.
⚡ And What About Battery Drain?
Yes, it uses a bit more battery — but that’s where the charging case saves the day. With the S1 Pro, just drop it into the charging case after use and it’s ready for your next session. No hunting for a cord. No panicked low-battery beeps in the middle of a workday.
(If you’re using the S1 base model, make sure to grab a backup battery pack or charger. The charging case is sold separately — and currently hard to find in stock.)
đź’Ą Bottom Line
Eufy’s HeatFlow™ Technology isn’t a gimmick. It’s a thoughtfully integrated innovation designed to support efficient, comfortable pumping. It doesn’t replace great flange fit or a good routine — but it might just make it all work faster, smoother, and more effectively.
And yes, I’m watching closely as they prep to roll this out in the upcoming Eufy E20 — bringing this feature to more pumpers at a more accessible price point. 🎉
💡 Recap: Jessica’s Pro Tips for Using HeatFlow™
Start with 5 minutes of heat at the beginning of your pump
Add another 5 minutes around the halfway mark to boost additional letdowns
If you notice tingling or sensory overload, turn it down or off
Match your insert use wisely to avoid covering the heat zone
Keep that charging case handy and you’re golden!
🎥 Want to see this pump in action?
Check out my full video walkthrough here: Watch on YouTube
🧠Ready to geek out even more?
Read the full specs and explore our on-demand pumping workshops at Genuine Lactation On-Demand
Until next time,
Happy (and warm) pumping!
— Jessica 💜
IBCLC + Pump Tester Extraordinaire
