A proper boiler installation quote should name the exact boiler model, list the controls, flue, filter and any extras, state whether the system will be flushed, include removal of the old boiler and confirm the warranty length. It should be a fixed price, in writing, following a survey. If a quote is a single figure on a text message, it is not a quote, it is a guess, and the difference usually appears on the day.
Comparing quotes is hard because installers specify jobs differently. One includes a magnetic filter, another does not. One quotes a ten year warranty, another two. This guide breaks a quote into its parts so you can line two up side by side and see what you are really being offered.
What a complete quote includes
The boiler
The manufacturer, the model and the output in kilowatts. “A 30kW combi” is not enough; there are dozens. The model tells you the efficiency, the warranty available and whether the installer is accredited to offer it. If you are not sure the size is right, our guide on what size boiler you need explains how output is chosen.
The flue
Every new boiler gets a new flue. The quote should say whether it is a standard horizontal flue, a vertical flue through the roof, or a longer run with extensions and bends, because each is priced differently.
Controls
Building Regulations require a room thermostat and a timer or programmer on a new boiler, and installers often include thermostatic radiator valves. The quote should name what is being fitted. A smart thermostat, if included, should be named too.
System cleaning and protection
Look for a chemical flush or a power flush, a magnetic system filter and inhibitor. These are the items most often missing from a cheap quote, and they are what keeps the new boiler alive. Most manufacturers make the filter and the flush a condition of the warranty.
Pipework and making good
Any new gas or oil supply pipe, condensate pipework, alterations to the heating pipework and the making good of holes where the old flue came out should be listed. On a relocation, this section is where the real differences between quotes appear.
Removal and disposal
The old boiler, the old flue, and on a conversion the cylinder and tanks, should all be taken away. The quote should say so.
Paperwork and warranty
Commissioning with the Benchmark checklist, warranty registration with the manufacturer and notification to Gas Safe or OFTEC for the Building Regulations certificate. The warranty length and what it covers should be written down.
The price and its terms
One figure, stated as fixed, with VAT shown, and the payment terms. A small deposit is normal for a boiler that has to be ordered. A large deposit before a survey is not.
How to compare two quotes that look different
Write the sections above down the side of a page and fill in each quote against them. Gaps become obvious. If one quote leaves out the flush and the filter, add what they would cost before comparing totals. If one offers a two year warranty and the other twelve, think about what a repair in year five would cost. If one names a premium boiler and the other a budget one, read about the difference before assuming they are equivalent; our guide on whether cheap combi boilers are worth it is a fair place to start.
Questions to ask before you accept
- Is this price fixed, whatever you find on the day?
- Who exactly will do the work, and can I check their registration?
- How long will the job take, and when could you start?
- What is not included that I might need?
- Do you service the boiler afterwards, and what does the annual service involve?
Our guide on how to choose a boiler installer covers the wider checks worth making on the company itself.
Why the cheapest quote is often not the cheapest job
Missing items get added on the day, a skipped flush shortens the boiler’s life, a short warranty moves the cost of a fault onto you, and an installer who is hard to reach afterwards costs you time every winter. A quote that includes everything and is honoured to the penny is the one that turns out cheapest over the life of the boiler.
How DCI Boilers can help
DCI Boilers quotes every installation in Cornwall and Devon after a survey, at a fixed price that includes the boiler, flue, controls, filter, flush, removal, commissioning and paperwork, with manufacturer warranties of up to 12 years. Our engineers are Gas Safe and OFTEC registered and we service what we fit. See our gas boiler replacement page for what we install, or ask us for a quote and compare it line by line with anyone else’s.
Need help now? Call DCI Boilers on 07888 862 603 or get a free quote.
Frequently asked questions
Should a boiler quote be free?
Yes. A survey and a written quote should cost nothing and carry no obligation.
How long is a boiler quote valid for?
Typically 30 days, because boiler prices from the manufacturer change. The quote should state its expiry.
What if the installer finds a problem on the day?
With a fixed price after a proper survey, that is the installer’s risk. If something genuinely unforeseeable appears, a good installer stops and explains the options before doing anything that changes the price.
Do I need a quote for a like-for-like swap?
Yes. Even a straightforward swap should be specified in writing so you know which boiler, which controls and which warranty you are getting.