Virgin Media O2 has urged customers to keep their routers out of direct sunlight to prevent overheating and slower connection speeds.
The broadband provider's warning comes as the UK is braced for another scorching day with temperatures above 30C.
Customers are being asked to keep their routers out of direct sunlight to avoid slower connection speeds as many are still working from home.
A list of tips has also been published about how to boost the signal to the garden for those wanting to take their afternoon meetings in the sun and how to create a WiFi hotspot if the signal cannot reach.
The provider wrote: "Although we test our Hubs carefully at a range of temperatures, they are better off out of bright sunlight, just like your phone or laptop."
They explained that leaving the routers in direct sunlight can impact their performance and cause overheating and poorer WiF signal.
A Virgin Media spokesperson stressed there is no widespread issue of routers overheating and they are just providing information about the risk.
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They added it shouldn't be put in a cupboard or behind the TV as that can also reduce how far the signal can go.
Other things that can impact signal is if it is in the way of furniture, large electrical appliances and even big bodies of water like a fish tank.
A good placement is away from sunlight and in an open area and at least 3ft away from a cordless phone or baby monitor, they added.
Electrical devices generate heat and even though many have cooling systems, placing them in direct sunlight can still cause overheating.
A spokesperson for Virgin Media said: "We regularly provide advice to our customers on how to get the best from their services.
"There is no widespread issue of our hubs overheating due to the warmer weather and we carry out rigorous and extensive testing to ensure our products can operate effectively in a wide range of temperatures."
Catherine Hiley, broadband expert at Uswitch.com, told the MailOnline : "Just like laptops, phones and games consoles, routers require ventilation to get rid of excess heat. Therefore, you should avoid placing them in or near direct sunlight.
"Keeping it in a shaded area and ensuring the room is well ventilated should be enough to stop it from overheating. If you're using a fan to keep cool, make sure the router benefits from the moving air as well.
"If your router is regularly overheating, it could indicate that the device has an underlying problem or that it is getting too old to function properly. If this is the case, it may be worth asking your provider to send you a new router or purchasing a compatible one through a trusted retailer."
