Question: How long will the battery last?

The battery in the HT1 sensor device (model CR2477) generally have a 1 to 2 year lifespan (often closer to two), but there are a few details to consider when changing it.

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Typical battery life is 1-2 years; more in warm conditions and less in extreme cold.

Thankfully, it is a replaceable battery. You will mostly likely need to purchase the replacement online. They are uncommon at hardware stores, but you can find them for sale from quite a few different outlets such as Amazon and various specialized battery retailers.

When it's time to change it, the process is quick and easy. Just follow these simple instructions.

The easiest way to open the case is with an old credit card or similar plastic card. Hold the sensor with the back facing you (the side with the seam) and with the text upright. Using a corner of the credit card, slide back and forth along the top seam pushing inward until the card penetrates slightly (squeezing the left and right sides of the sensor can help).

Then slide the card along the top edge to the left side and pry outward and the back cover will come off. The circuit board will then come out on its own. It's positioned by two plastic pegs but is only held in by the back cover. The battery is on the back of the board. It's a CR2477 lithium coin cell. The + side of the battery should face away from the circuit board.

Reassembly is the reverse, with one trick: it's easier to replace the back cover if you put the top side in first, as the bottom has two smaller pegs that are designed to snap in more easily.

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