If you've ever had a watch battery replaced, you may have been told that water resistance can't be guaranteed afterwards. It's a fair thing to wonder about. After all, you only came in for a new battery, so why would that change anything?
Here at Parrys of Malvern, we're always upfront with our customers about this, because we'd much rather you understood what's going on inside your watch than find out the hard way after a swim. So let's explain what water resistance actually is, why a battery change can affect it, and what you can do to keep your watch protected.
First things first. No watch is truly "waterproof". That's why manufacturers use the term water resistant instead. It means the watch has been built to keep water out up to a certain point, under certain conditions.
That protection comes from a set of small rubber or synthetic seals, often called gaskets or O-rings. You'll find them in a few key places:
Each of these seals needs to be in good condition and sitting perfectly in place for the watch to stay water resistant.
To reach the battery, the caseback has to come off. That means the seal underneath it is disturbed. Even when it's refitted with great care, an older seal may not sit quite the same way it did before, especially if it has flattened or lost its shape over time.
This is the big one. Rubber seals don't last forever. Over the years they dry out, harden, shrink or crack. A watch that was perfectly water resistant when it was new might have lost much of that protection long before the battery ran out. Opening the case can reveal a seal that's already past its best.
A battery change involves the caseback. It doesn't involve the crown, the pushers or the glass. If any of those seals have worn, the watch may already let water in, and a simple battery replacement won't fix that. That's why we can't honestly promise a watch is water resistant just because the caseback has been closed up properly.
Everyday life takes its toll. A knock against a door frame, a dropped watch or a slightly loosened crown can all compromise water resistance without any obvious sign on the outside.
Hot showers, baths, saunas and hot tubs cause the metal and seals to expand and contract at different rates, which can weaken seals over time. Soaps, shampoos, sun cream, perfume and chlorine can also break down rubber gaskets faster than you'd expect.
When a jeweller tells you water resistance can't be guaranteed after a battery change, it's not about cutting corners. It's simply being honest. Seals wear out over time, and a battery change only involves one of them, so there's no way to promise the whole watch will keep water out just because the back has been closed up carefully.
At Parrys of Malvern, we'd always rather give you the full picture. If your watch is one you wear swimming, in the bath or out in all weathers, just let us know when you bring it in and we'll talk you through the options.
Many people are surprised to learn that the depth shown on a watch doesn't mean you can take it that deep. The number is a technical rating rather than a real-world guide to swimming or diving. As a rough guide:
If you're not sure what your watch is rated for, have a look at the caseback or dial, or bring it in and we'll happily check for you.
A little care goes a long way. Here are some simple habits that help:
If you notice fogging under the glass, droplets inside, or the watch stops after getting wet, don't wait. Moisture can quickly cause rust and corrosion in the movement. Bring it to us as soon as you can and we'll take a look and advise you on the next steps.
Parrys of Malvern has been caring for local watches and jewellery since 1952. As an independent, family-run jeweller at 115 Church Street in Great Malvern, we offer watch battery replacements alongside a full range of watch and jewellery repairs.
We take the time to explain what we find, whether that's a simple battery change or something that needs a little more attention. And if you're thinking about a new watch that suits a more active lifestyle, take a look at our watch collection, featuring brands such as Sekonda and Rotary.
If you'd like your watch battery changed, or you want advice on keeping your watch protected from water, visit us at Parrys of Malvern, 115 Church Street, Malvern, WR14 2AJ. We're open Tuesday to Saturday, 9.30am to 4.15pm. You can also call us on 01684 574077 or get in touch online.
We'll keep your watch ticking, and help keep the water out too.

