https://makerworld.com/en/models/2613834-iqflow-2200-water-meter-braket-fur-ir-sensor
Battery lifetime notice
Reading the meter via the IR interface has a direct impact on the battery lifetime.
According to the manufacturer, the expected lifetime is around 16 years – however, regular polling will reduce this.
The exact impact is currently hard to quantify and needs to be observed over time.
For this reason, I have:
- increased the polling interval to 120 seconds
- disabled additional values such as flow (L/h) and temperature
- and explicitly included battery-related data to monitor long-term effects
I just tested and putting a piece electrical tape over the TX did the trick. Thanks for the help!
@CloudMass
I can read data for about 12-14 hours until it stops. I have to trigger the magnet again by removing the sensor and put it back into position. Do you have the same issue?
How did you mount your sensor?
Mine has been continuously reading data for a few days now without issues. At the moment I have just carefully placed the ESP on the meter and hope to god that it does not get bumped 
I’ll have to look into printing that bracket.
Good and bad news for me 
Can you share a picture of your position - without - touching it!
Seem, that I have to improve my braket.
@CaneTLOTW does it now work continiously?
In which part of denmark do You live. I live in Egedal. Ir seems here to have been blocked by Novafos
In theory yes. But seems like in practise that this is not true.
Have had this running with 16 seconds poll, for a year now. And the battery days left has only descended in a positive way. Used to go down at 04:34 and now it is going down at 04:39. So unless that is just an internal counter, then I would say we are alright.
Did you get it working?
I am thinking of using one of theese
Together with an poe esp device, i dont like running stuff in usb chargers if i can avoid it. I should be able to use your code and modify it for another esp.
Did you add some magnets or was it enough with the one in the wattwätcher?
I use the Wattwächter and it works very well.
I had to flash it from Tasmoto to ESOpHome.
I'm reading every 60 sec and have a forced restart of the ESP in the code every 24h.
It now works already for 5 days without interruption.
I ended upp buying one from Christians teknikshop, since wattwächter dont ship to sweden. Got it working but it stops after a while, different time every time. Restart dont help, only thing that works is if i remove the device from the meteter and put it back. I suspects the magnets isnt strong enough and have ordered a couple to test with
I had the same issue. Some water meters simply stop after x minutes. Then I need to remove and put it back onto the meter. No way for me to do it with permanent mount. Someone built a solution with a servo motor which removes it automatically.
Maybe an electromagnet will fix the problem
Before building servo contraptions: the flowIQ 2200 continuously broadcasts its readings via wireless M-Bus. Kamstrup / your utility can provide the AES key for your own meter (see the two official docs below) — with the key, any wM-Bus receiver reads it without touching the meter at all.
My water company refuses to share the key...
"Refuses" is worth pushing back on — politely and with paperwork. Two official Kamstrup documents show that sharing meter keys with end customers is an intended, supported process, not a security exception:
- Register, download and distribute encryption keys — describes how customers can download keys for their meters, and how distributors can assign separate read rights.
- Change ownership of encryption keys — describes transferring/requesting key ownership between organisations via Kamstrup's EKS portal.
The "read rights" part matters: the wM-Bus AES key is decrypt-only — it lets you read the broadcasts your own meter already sends through your walls every few seconds. It gives no write or configuration access. If the utility claims otherwise, ask them to point at the mechanism.
So instead of accepting a flat "no", ask them in writing:
- why the Kamstrup-provided key distribution process can't be used in your case,
- what legal basis the refusal rests on,
- and — if they still won't hand over the key — what machine-readable alternative they offer for accessing your own consumption data.
That last question has teeth in the EU since 12 September 2025: the EU Data Act (Regulation 2023/2854, Art. 4(1)) requires the data holder to make readily available product data accessible to the user "easily, securely, free of charge and in a comprehensive, structured, commonly used and machine-readable format". That may not literally entitle you to the AES key — but it does mean "no, on principle" is not a complete answer anymore. Utilities tend to respond differently once the question is phrased that way.
They keep blaming gdpr and because they cant change the encryption i can sell my house but sit in the car outside and see how much water the new owner uses...