eufy Security Flood & Freeze Sensor E20 Review: HomeBase Leak Alarm With a Probe
The eufy Security Flood & Freeze Sensor E20 is a battery leak and freeze disc for households that already run a US eufy HomeBase. It sits on the floor or tucks a 1.2 m probe under an appliance, sounds a 75 dB local alarm when water hits both pins, and can warn before pipes freeze with five temperature thresholds. The five-year CR123A and IP54 housing make it a set-and-forget add-on for a kitchen, laundry or basement. The hard limit is the HomeBase: without Mini, HomeBase 2, 3 or Pro it does nothing, and it has no Matter, Apple Home, Google Home or Alexa leak-sensor path. Distinct from the older T8920 Water and Freeze Sensor, this is the E20 generation with the extension probe and the louder on-device buzzer.
- Existing eufy HomeBase households
- Kitchens, laundry rooms and basements
- Buyers who want a local siren, not only a phone ping
- Tight spots that need a probe under an appliance
One sensor per water source: kitchen, bathroom, laundry.
Buy on Amazon USACheck priceBuy on Amazon CanadaPros
- Detects both leaks and freezing pipes, with five freeze thresholds in the app
- 75 dB on-device buzzer plus LED so you can find the leak in the room
- 1.2 m extension probe for gaps under appliances
- CR123A battery rated for five years
- IP54 housing for damp utility spaces
- Works with Home Assistant through the community eufy Security integration
Cons
- Requires a compatible US eufy HomeBase, it is not a standalone Wi-Fi sensor
- No Matter, Apple Home, Google Home, SmartThings or Alexa leak-sensor path
- No everyday temperature reading, tilt or tamper contact
- Warranty is not published on the spec sheet
Who is the Flood & Freeze Sensor E20 for?
This sensor is for someone who already owns a US eufy HomeBase and wants leak and freeze coverage next to a water heater, washing machine, fridge, sink or basement pipe. It is not a standalone Wi-Fi gadget: the radio is Sub-1G back to the HomeBase, which is what carries Wi-Fi and the phone alerts. That also means it can sit where 2.4 GHz is weak, as long as it is within about 200 m of the base in open air. The 1.2 m extension probe is the reason to pick the E20 over a disc-only sensor, because the thin probe reaches under an appliance where the round body will not fit.
What the Flood & Freeze Sensor E20 offers
Two hazards, one puck. Water has to touch both metal pins, or the probe, to trigger; freeze alerts fire below 4 C, with five alarm points in the app from 32 F to 40 F. When a leak is found the unit itself buzzes at 75 dB and the LED blinks red, so you can find it in a utility room without unlocking a phone. The CR123A is rated for five years, the housing is IP54, and a low battery makes the LED flash red every minute. Pairing is a two-second sync-button press into the eufy app under the HomeBase. Home Assistant can see HomeBase sensors through the community eufy Security HACS integration that already covers this line.
What to know before you buy
It will not work without a compatible US HomeBase (Mini v4.0.5.2 or newer, HomeBase 2 from after 2021, HomeBase 3, or HomeBase Pro). There is no Matter, Apple Home, Google Home, SmartThings, Zigbee, Z-Wave or Thread path, and Alexa has no water-leak device type to map onto. It does not report everyday temperature, only freeze-risk thresholds, and it has no tilt or tamper contact. The official US storefront currently sells an 8-pack; the single unit is the Amazon listing. Warranty is not published on the spec sheet used here. This is a different model from the catalog's older T8920 Water and Freeze Sensor.
Is the Flood & Freeze Sensor E20 worth it?
Inside an eufy Security house it is a cheap extra layer: a local siren, a probe, a five-year cell and freeze thresholds on a disc you can drop next to a water source. Outside that ecosystem it is the wrong buy, because the HomeBase is not optional and none of the big voice platforms expose a leak sensor of this kind. If you need a Matter or Zigbee leak disc that talks to Apple Home or Home Assistant natively, look at those protocols instead of this one.
Frequently asked questions
Does the eufy Flood & Freeze Sensor E20 need a hub?
Yes. It talks Sub-1G to a US eufy HomeBase: Mini (v4.0.5.2 or above), HomeBase 2 (v3.4.1.2 or above, released after 2021), HomeBase 3 or HomeBase Pro. Without one of those it cannot pair or send phone alerts.
Does the Flood & Freeze Sensor E20 work with Home Assistant or Apple Home?
Home Assistant can reach HomeBase sensors through the community eufy Security HACS integration. Apple Home, Google Home, SmartThings and Matter are not supported, and Alexa has no water-leak device type for this sensor.
Does it have a local alarm, or only phone notifications?
Both. A leak sounds a 75 dB buzzer on the disc and blinks the LED red, and the HomeBase can push a notification to the eufy app.
What battery does the Flood & Freeze Sensor E20 use?
One CR123A cell, pre-installed, rated for five years. When it is low the LED flashes red every 60 seconds.
Is this the same as the older eufy Water and Freeze Sensor?
No. The catalog already holds the T8920 Water and Freeze Sensor. The E20 is model T90F0, with the 1.2 m probe, a 75 dB local buzzer and a five-year CR123A.
