Getting a new boiler installed is a significant investment, and for most people it’s not something they do more than two or three times in their lifetime. That can make the whole process feel a bit daunting — especially when it comes to understanding what a good job actually looks like, and how to tell whether you’re getting one.
This guide walks through the full process of a boiler installation in Kent so you know exactly what to expect, from the initial survey through to the engineer leaving your home with everything running correctly.
Step one: survey and quote
A reputable heating company will always want to survey your property before providing a final quote. This isn’t bureaucracy — it’s essential. The engineer needs to understand the size of your home, your hot water demand, the location of your existing boiler and flue, the current state of your pipework and controls, and whether any additional work is required. Quotes provided without a survey are estimates at best, and they often increase when the engineer actually arrives.
At David Osborne Heating, we carry out pre-installation surveys across East Kent at no charge. The quote you receive after a survey is the price you pay — we don’t add surprise extras on the day.
Step two: choosing your boiler
Your engineer should guide you through the options that suit your home rather than simply selling you the most expensive unit. The key considerations are boiler output (measured in kW, which needs to match your home’s heating demand), fuel type (almost all new installations in Kent are gas, though we also work with oil systems), and whether a combi, system, or regular boiler is most appropriate for your property.
We work with all major manufacturers including Worcester Bosch, Viessmann, Baxi, Ideal, and Vaillant — and we’ll always explain the trade-offs between different models honestly.
Step three: the installation
On installation day, the engineer will typically start by draining down the existing system and removing the old boiler. New pipework connections are made, the new boiler is fitted and connected to the gas and water supplies, and the flue is installed or adapted as required. If a magnetic filter is being fitted (recommended for all new installations), this goes in at this stage.
Once the physical installation is complete, the system is refilled, pressure-tested, and commissioned. Commissioning means the engineer sets the boiler up to manufacturer specifications — gas pressure, flow rates, controls configuration — and confirms everything is operating correctly. This stage is critical and shouldn’t be rushed.
Step four: handover and certification
Before leaving, the engineer should walk you through the new boiler’s controls, show you how to repressurise the system, and explain what to do if you notice any issues. You should receive a Gas Safe certificate for the installation, and the engineer should register the boiler with the manufacturer on your behalf (or confirm you’ve received the details to do so).
Building Regulations notification is also required — as a Gas Safe registered company, we handle this automatically as part of every installation.
Frequently Asked Questions
Q: How long will my new boiler installation take?
A: Most standard replacements take one to two days. More complex jobs — moving the boiler location, converting system types, or significant pipework changes — can take two to three days.
Q: Do I need to be home during the installation?
A: Yes, or you should arrange for a responsible adult to be present throughout. Engineers need access to various parts of the property, and you’ll need to be there for the handover.
Q: Will the engineers make a mess?
A: There will inevitably be some disruption — pipework may need to be accessed through walls or floorboards in some cases. Good engineers protect floors and work areas and clean up thoroughly before leaving.
Q: What if something goes wrong after installation?
A: Reputable companies will address any post-installation issues promptly. We provide an aftercare service for all our installations in East Kent.
Q: Is my existing pipework suitable for a new boiler?
A: In most cases, yes — particularly if your existing system is not too old. The survey will flag any concerns, and if any pipework upgrades are needed they’ll be quoted separately before any work begins.