Rain sensors: accuracy, durability, integration (not DIY)

Regularly the question comes up which rain sensor works well. I checked various threads but there is no continuity on this and some are really old.

Since weather apps (I now use OpenWeather) do not work well for me (it rains and the app does not show it), I am looking for a solid rain meter that integrates with Homey.


  1. Accuracy: measure how many mm falls every day.
  2. Wireless: zwave preferred, wifi if needed.
  3. Power: preferably not a battery operated device.
  4. Durable: can it work for a few years?
  5. Integrates well with Homey.
  6. Not a DIY project

I prefer to not not spend on something that does not last and replace it more often if that sums to less than €25 per year. Maximum cost €150

Any tips?

Feel free to add your experiences (mention make and model) and this thread can perhaps provide some continuity.

How about this: https://www.amazon.co.uk/dp/B09MHDPY34/ref=sspa_dk_detail_6?psc=1&pd_rd_i=B09MHDPY34&pd_rd_w=mJfne&content-id=amzn1.sym.15c0cc83-c6c5-4d44-aa3d-0de17a9f3682&pf_rd_p=15c0cc83-c6c5-4d44-aa3d-0de17a9f3682&pf_rd_r=60K3DK6JVW0G9CBWTNKB&pd_rd_wg=ffCss&pd_rd_r=ea92dd80-386c-447b-80c7-ffc88e611191&s=outdoors&sp_csd=d2lkZ2V0TmFtZT1zcF9kZXRhaWw
Integrates with Homey using my Misol and Ecowitt app.

The only Z-Wave rain sensor I know that is compatible with Homey is the POPP Z-Rain Sensor. But it uses batteries and I have no personal experience with this device, sorry.
But I have the POPP Z-Weather, about 2 years, and the POPP Outdoor Siren 2, about 3/4 year, in use, and so far I have had no bad experiences with either device.

Note: Many rain sensors determine the amount of rain via a rocker with two paddles (see photo). In order to detect whether it’s raining, one of these paddles must first fill with rainwater and then tilt due to the weight. Depending on the strength of rain, it can take up to several minutes until the rain sensor recognizes that it’s raining. If you want the awning to close automatically at the first raindrops for example, you have to use a different type of rain sensor.

Thanks for the tip! Although it requires batteries, I like the solar panel which may delay me going up the roof to replace batteries.

The Ecowitt Wittboy WS90 or WS90AE-DE looks like a winner, be it significantly more expensive.

I want to start small and cheap though and expand as I like.
Do you think the Self-Emptying Rain Collector Rainfall Sensor Ecowitt WH40 and the new LAN/WiFi Ecowitt GW2000 gateway will work together (both 868 MHz)?
How will the rain collector empty itself?

Estimated cost gateway + mechanical rain collector/sensor €125.

Thank you for this. I use a lot of z-wave and I see this device uses standard AAA and very little power if configured correctly.

I do not need speed, just want to know how many mm water fell in a day. I use it to prevent water irrigation.
During a rainfall the POPP Z-Rain reports the amount of rain every 1024 seconds in m3 (total sum of the rainfall), mm per m2 and mm/h (current strength of the rainfall). How do I calculate it?

How will it empty itself?
Does it need to be set horizontal for the rocker to work?
When there is strong wind, can I connect it to the underlying floor?

Available for €80.

The WH40 and GW2000 should work OK. The batteries should last well over a year, probably 2 or more. I have the weather station with the solar panel and the batteries are still OK after 3 years.
The operation is the same as the POPP unit where the see-saw rocks back and forth as one side fills up followed by the other. Once the bucket is full the see-saw tips and empties while the other side starts to fill. This does mean they need to be mounted level for the action to work correctly.
The update rate from the sensor is around 15 to 30 seconds and provides the following (except Ultraviolet):

All of which are available in the flows.
Once you have the GW2000, you can expand the system to include moisture sensors. I have these in various places in the garden so I know if it is OK to skip irrigation based on the soil moisture content.

Note: the rain sensor doesn’t need to be mounted up high, like a wind sensor does, as it will catch rain in any space that is not covered.

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I’ve looked in the app store (trigger cards) and in the manual, and I have absolutely no idea how to calculate this at the moment, sorry.
But I asked an friend, maybe he has more information.

When the rocker tilts, the water runs out of the paddle through slots in the bottom of the sensor.


Don’t know exactly, but this is what is written in the manual:
The base (1) contains the gauge and a indicator to place it on a flat surface.

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@Adrian_Rockall: Do i need the gateway of this Ecowitt Wittboy WS90, to work with Homey?

Yes, it does appear that is the case. From the link above:

Multifunctional weather station accessory WS90: An accessory that needs to be paired with the gateway or console cannot be used alone.


Support linking with Gateway GW2000/1100/HP2564 consoles: monitor the weather conditions in your home and garden

Did you hear back?

More info in this thread . Let’s continue there.

Any owner of the POPP Z-Rain is invited to read here on how to use its readings.
Your help will be appreciated.

I own the Netatmo Rain Gauge(Wifi)I have the indoor and outdoor module. Works great. Outside battery operated, about 1 ½ - 2 years for the battery.

Rain gauge is self emptying. Everyday restarts @ 0.00mm. Has his ownn app for Homey and netatmo’s own app for your smart phone. As noted it also has a tumbler. It takes some while before it tumbles the first time(mostly 0.1 mm), so no direct guarantee it starts to rain.

Works pretty ok for me for years now.

Indoor module( nescessary, the rest is optional)

Outdoor Module

Rain Gauge

Netatmo’s App

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@Marcel_Ubels Thank you, it is a very impressive design and report.
Weather station with Rain Gauge for €189.

Anybody using a Gardena rain sensor?

Yeah quite pricey, but works good. But including a co2 meter inside, moisture meter in and outside, thermometer in and outside and noice meter. The noice meter has no value for me, because it doesn’t mute( my wife).durability is very good(have them about 5 years), only the mounting kit for the rain gauge is not that durable because it got broken after three years.( screw broke)

@Marcel_Ubels Thank you for the info.

Gardena electrical rain sensor

I see it is a 5 meter wired sensor (seen for €40), but still requires a 9V battery. To be connected into any of the Gardena listed irrigation control computers. There is a Homey app for Gardena, but it does not show this sensor so may have to rely on the Gardena app.


It states expired product.

Btw, I use also the Netatmo WS for more than 4 years. In my experience it is very reliable. Once I had a broken battery cover, but it was replaced free of charge by support.
In addition, I have Tempest WS from WeatherFlow in use and am also very satisfied with it. In comparison to the Netatmo WS, the Tempest provides much more weather data:

The Tempest WS provides even more information, such as weather forecasts, but unfortunately this data has not yet been integrated into the Homey app. In Home Assistant, these data are integrated. If you need a listing, let me know.
Because the Tempest uses solar panels and a rechargeable battery, it is completely independent. However, the purchase price is also significantly higher.

Btw, the Gardena Rain Sensor also does not seem to work with Gardena Smart System. So I guess there is no way without DIY to integrate it to Homey.
The Smart Sensor, a soil moisture sensor, from Gardena works with Homey. But in addition you need the Gardena Hub.

A much cheaper alternative to the Smart Sensor from Gardena is the WH51 Wireless Soil Moisture Sensor from Ecowitt. I have 4 of them in use myself. A maximum of 8 sensors can be connected to one Ecowitt GW1100 WiFi gateway.
These sensors are also supported by @Adrian_Rockall Misol and Ecowitt app.
Instead of a complete weather station, you can also use only the WH40 Wireless Self-Emptying Rain Collector Rainfall Sensor from Ecowitt.

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I use Ambient Weather WS-5000 Ultrasonic Professional Home Weather Station & Thermo Hygrometer which is pricy, but I it can be bought in pieces.
I think that it’s nice to have the rain sensor separated from vind and other sensors. The best position for vind and rain sensors are not the same!
I have added some special sensors also, all of them is batt. powered, one (eath moist) is more heavy on the batt. I think that it’s on the edge of the networks capability.
It integrates smoothly with Homey using Adrians app. It also integrates with Ambient Weather.com and Weather Underground and more.
I have had it for about 2 years, no change of batt. except the one mentioned.
Base station (console) and vind sensor can be powered by wire.

Just my 2 cent.

  • Kurt
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After buying, I can now recommend the zwave gauge of POPP Z-Rain. Relatively cheap, simple and effective.

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Is this rain sensor usable without any additional hub? I’m looking for a standalone sensor what directly connects to the homey pro hub. Is this possible?