---
title: Water tank monitor Battery Replacement (pre may 2022)
description: T35 Battery Replacement
---

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# Water tank monitor Battery Replacement (pre may 2022)

## Once you have your battery kit, please read carefully and follow the instructions step by step to replace the battery.

![](https://help.waterwatch.io/3.0.1/~gitbook/image?url=https%3A%2F%2F3663084420-files.gitbook.io%2F%7E%2Ffiles%2Fv0%2Fb%2Fgitbook-x-prod.appspot.com%2Fo%2Fspaces%252FUHGkYdZf2x89OKqHUwwA%252Fuploads%252FcKTMkdQAbahaMuwQFTq4%252Funscrew%2520base%25201%2520WHITE-01.png%3Falt%3Dmedia%26token%3D15422fe9-0f37-468e-b70b-91e87e0ebd81&width=768&dpr=4&quality=100&sign=19e9a907&sv=2)

1\. Unscrew the top case anti-clockwise and remove.

![](https://help.waterwatch.io/3.0.1/~gitbook/image?url=https%3A%2F%2F3663084420-files.gitbook.io%2F%7E%2Ffiles%2Fv0%2Fb%2Fgitbook-x-prod.appspot.com%2Fo%2Fspaces%252FUHGkYdZf2x89OKqHUwwA%252Fuploads%252FTDLE8lFlrPDOLI5Nhwbr%252F2%2520Remove%2520radar%2520%2526%2520case-01.png%3Falt%3Dmedia%26token%3D261b5b56-09ef-42da-ae64-032696fbdd7d&width=768&dpr=4&quality=100&sign=75f332d1&sv=2) 

2\. Gently pull the radar, internal case and battery from the top case. 

![](https://help.waterwatch.io/3.0.1/~gitbook/image?url=https%3A%2F%2F3663084420-files.gitbook.io%2F%7E%2Ffiles%2Fv0%2Fb%2Fgitbook-x-prod.appspot.com%2Fo%2Fspaces%252FUHGkYdZf2x89OKqHUwwA%252Fuploads%252FC4gG9N3EsJWIaOEHbwEO%252F3%2520Unplug%2520old%2520battery-01.png%3Falt%3Dmedia%26token%3D90971a9f-6443-4a24-a494-de0c14847be1&width=768&dpr=4&quality=100&sign=47f2f4e0&sv=2)

3\. Carefully unplug the battery cable from the circuit board. Plug your new battery in.

 ![](https://help.waterwatch.io/3.0.1/~gitbook/image?url=https%3A%2F%2F3663084420-files.gitbook.io%2F%7E%2Ffiles%2Fv0%2Fb%2Fgitbook-x-prod.appspot.com%2Fo%2Fspaces%252FUHGkYdZf2x89OKqHUwwA%252Fuploads%252FQtpio4L5AvDMKJ9kklFS%252F4%2520Slide%2520battery%2520into%2520case-01.png%3Falt%3Dmedia%26token%3D4754b121-192b-4e78-bf7e-512c943e2208&width=768&dpr=4&quality=100&sign=7ee5b1e9&sv=2)

 4\. Place the new battery into the cradle in the top case. The battery wires should be placed on the left side of the cradle.

![](https://help.waterwatch.io/3.0.1/~gitbook/image?url=https%3A%2F%2F3663084420-files.gitbook.io%2F%7E%2Ffiles%2Fv0%2Fb%2Fgitbook-x-prod.appspot.com%2Fo%2Fspaces%252FUHGkYdZf2x89OKqHUwwA%252Fuploads%252F5URfR1VdT4IrjhvVWYyr%252F5%2520Slide%2520internal%2520case%2520in-01.png%3Falt%3Dmedia%26token%3D2419d63c-84e9-4b19-a424-a3c18bf2d8ae&width=768&dpr=4&quality=100&sign=4492a3de&sv=2)

 

5\. Slide the internal case and radar into the top case over the battery. Keep the wires to the left and be careful not to pinch the battery wires between the internal case and the top case.

Push the top case and radar together to compress the o-ring.

![](https://help.waterwatch.io/3.0.1/~gitbook/image?url=https%3A%2F%2F3663084420-files.gitbook.io%2F%7E%2Ffiles%2Fv0%2Fb%2Fgitbook-x-prod.appspot.com%2Fo%2Fspaces%252FUHGkYdZf2x89OKqHUwwA%252Fuploads%252Fuv3IqID1nmeBAnX7n5B5%252F6%2520Screw%2520Base-01.png%3Falt%3Dmedia%26token%3D8cbbf715-fc77-42f3-9585-d36b0933200b&width=768&dpr=4&quality=100&sign=1de685f2&sv=2)

6\. Screw the base back on and you’re good to go! Make sure the cover is tightly screwed on to prevent water and dust from damaging your sensor.

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