I noticed a bit of water at the bottom of our refrigerator. It's probably because I still need to cut a hole in the sill and put in the plastic vent but it's one of those tasks that's still on the to-do-list. Whilst I was cleaning the refrigerator anyway I shot a few pictures to show the sensor we put on the door. It's a 433.92MHz DS10A Door Sensor with a longer cable attached. Mounting was easy using the supplied double-sided tape.
I mounted it on the inside of the door so you hardly notice it. Has been working fine for over a year now. The DS10A itself is located underneath the kitchen cabinet behind the sill.
