A professional boiler installer will survey your home and ask you questions about your hot water needs, such as if you may need to use hot water from two sources at the same time (e.g. someone using the shower while hot water is required when washing the dishes in the kitchen), or whether you use a pumped power shower. The engineer is developing a usage profile for your via asking such questions, and thus can make an informed decision on which boiler is most suitable for your home.
The initial survey should be fairly detailed, and expect a lot of questions, some of which you may not know the answer to, but the engineer can perhaps answer by finding things out like how many people live in the house, and inspecting the bathroom and kitchen areas to get an idea of your hot water needs by observation. The engineer may ask you about events like Christmas, and if you have a number of guests staying over for prolonged periods of time...again, to get an idea of potential maximum usage.
The installer should offer you a range of suitable boilers for your home based on your needs, giving you some room to choose within a selected range to meet your own budget. The engineer should guide you on which brands are the most reliable - you have to weigh up reliability and likely longevity of a boiler versus costs.
While your engineer is surveying your property, it's important to have some questions prepared as it's a good opportunity to get their opinion on your current heating system. You should get their opinion on your current radiators, heating controls, tips about conserving heat - that kind of thing. They will be taking such considerations into account anyway, but it's certainly wise to prepare such questions to ensure you can make more informed decisions regarding your home's heating system.
Once your new boiler is installed, the engineer will run a series of performance and safety tests to ensure it's installed properly. The engineer will record these tests usually in the back of the instruction manual. These tests create a benchmark which is important for your warranty. Of course, in the days after the installation, you should keep a vigilant eye on its performance. If you notice anything untoward, call the engineer's company and notify them.
The final point is the most important: a good engineer can explain things clearly to the layperson. If you're left feeling confused by an engineer due to too much technical information, it's always worth getting a second opinion (another survey by another heating/plumbing company). It's very important that an engineer can reassure the home owner WHY a particular range of boilers are most suitable for the property and the home owner's needs so they can make an informed decision. Article kindly provided by kentishplumbers.co.uk