You cannot use boiling water for your hot water bottle. Pouring boiling water into it may damage it, creating cracks and tears. This in turn may lead to your bottle leaking, making your hot water bottle unsafe to use.
Instead of boiling water, pour hot water into your bottle. If you use a kettle, wait 10-15 minutes after the water is finished boiling before pouring it into the hot water bottle. You can also fill your bottle with hot water from a tap.
Are some hot water bottles resistant to boiling water?
To the best of our knowledge, no hot water bottles on the market are designed to resist boiling water over long periods, with a guarantee of not getting damaged.
In fact, you’ll find a sign on most hot water bottles explicitly advising against using boiling water. Below is an example of a Fashy hot water bottle, made in Germany.
Can I use boiling water if there is no sign on my bottle?
In the unlikely case that this message is not on your hot water bottle, avoid using boiling water anyway. Stay on the safe side and use hot water from the tap or water from your kettle after letting it cool down for at least 10 minutes.
In addition to being a safer option, not using boiling water will increase your hot water bottle's longevity and prevent you from buying a new one every year.
Why is damaging your hot water bottle dangerous?
An important rule when using a hot water bottle is safety first. This means using an item that adheres to British standards (B.S 1970:2012), is in good condition, and does not have any holes or tears. If your hot water bottle has holes or tears, it may leak and cause serious burn injuries.
Although hot water bottles have many benefits, it's of crucial importance to give safety the highest priority when using them.
What can I do instead of using boiling water?
1. If you have a silicone hot water bottle, use a microwave
Only place your hot water bottle in the microwave if it’s made of silicone and microwave safe. Do not use the microwave unless you’re 100% sure it’s suitable. Read our latest article explaining how to know whether your hot water bottle is microwave safe.
If it is, fill the hot water bottle up two-thirds and follow the manufacturer’s instructions on how long you should heat it. It typically takes 2 to 3 minutes for a hot water bottle to heat in a microwave.
2. Use a kettle and let it cool down
If none of the options above is suitable for you, boil water in a kettle and let it cool down for about 10 minutes. That way the water won’t be boiling anymore and is safe to be poured into your hot water bottle.
Once the water in your kettle has cooled down, follow the same typical procedure, unscrew the stopper, carefully pour water into the bottle, and conduct a short test to make sure the hot water bottle is safe for use. Again, use a cover to keep your bottle warm longer.
3. Do not use hot water from the tap
Although this is the fastest and cheapest alternative, you shouldn't use hot tap water to fill your hot water bottle. The water may contain impurities (minerals and other toxins for example) and damage the inside of your bottle.
Instead, use water boiled from your kettle after letting it cool down as presented in the section above. Once you’ve reached two-thirds of your hot water bottle capacity, screw the stopper back on. Make sure the bottle is well sealed by turning it upside down and gently squeezing it over the sink.
If you want to keep your bottle warm longer, use a cover. Here are more tips on how to keep your hot water bottle warm for as long as possible. Using a cover for your hot water bottle is also generally advised to prevent direct contact between the bottle and your skin.