Watch out for frozen pipes this winter! When sizing your boiler, there are some key factors which will influence how big an appliance you’ll need. Whatever your choice, it’s essential to shop around and speak to as many installers and providers as possible happy heating! If you are planning to remodel your kitchen or bathroom, our. Thank you for the clear and practical advice it’s saved me stress, time and money! Size isn’t the only factor that can affect the cost of a new boiler - the type of boiler.