What is a combi boiler?


What is a combi boiler and how does it work?

A combi boiler (or combination boiler) is a high-efficiency water heater and central heating boiler, combined within one compact unit. Hot water is provided on demand rather than stored in a water tank means you can have a nice hot shower, run a long bath or have the heating on all day without having the worry of running out of hot water.

Why you should choose a combi?

  • You'll get infinite hot water whenever you turn on the tap or shower because it heats water straight from the mains.
  • Perfect for homes that are short on storage space as you do not need any water tanks or cylinders.
  • They work well if you live in a house with limited space.
  • They've got fewer parts to install, so tend to be quicker to install.
  • Highly efficient when compared to older boiler models.
  • Installation costs are typically cheaper than standard or system boiler

Things to think about before choosing a combi boiler.

  • If you use more than one tap at a time, it could reduce the flow of hot water.
  • But that does also depend on the strength of your mains water pressure.
  • Your water might take a few seconds to heat up.
  • Power showers cannot be installed with these boilers

Why choose a Worcester Bosch combi boiler?

Worcester Bosch boilers have won Which? Best buy for gas boilers for the last 9 years running highlighting the quality, energy efficiency and all-round performance of the full Worcester Bosch range. To read more about Worcester Bosch and Which? visit:https://www.worcester-bosch.co.uk/products/boilers/which-best-buys

Is a combi boiler cheaper to run than other types of boiler?

The Energy Saving Trust says whether a combi or a standard boiler is cheaper to run depends completely on your lifestyle.

A combi boiler is more economical to run as a result of not needing a hot water tank, which helps to keep costs down. And are cheaper to run if your household doesn’t use too much water. Combi boilers can be more efficient as they don’t leave water sitting in a tank where it can lose some of the heat.

Regular boiler, for example, tends to produce hot water twice a day, regardless of if it gets used or not – in the morning and in the evening. This requires the boiler to fire up to produce the hot water even if it doesn’t get used the water simply cools down, which will waste a lot of energy over time.

I don't have a combi boiler, should I switch?

If you have a small to medium-sized house where space is at a premium, then combi boilers are a fantastic choice due to their compact size. Some models are even small enough to fit in a standard kitchen cupboard.

What size combi boiler do you need?

KW output Bedroom Radiators
24 - 27Kw 1 - 2 bedrooms 10 Radiators
28 - 34Kw 3 - 4 bedrooms 15 Radiators
35 - 42Kw 4+ bedrooms 20 Radiators

There are many factors that you need to consider when choosing the right boiler for your home, e.g. the number of bath and showers. The above table should be used as a guide only but please be aware you might need a different sized boiler based on your lifestyle.

How much does a combi boiler cost?

  • Swapping your existing combi with a new one – starting from £1,795 + VAT (labour & parts)
  • Converting from a Standard, system or back boiler to a Combi boiler – starting at £2,645 + VAT (labour & parts)

Included within your fixed price from us

  • Gas Safe installation
  • FREE Honeywell Smart Thermostat RRP £199.99
  • FREE Worcester Bosch magnetic filter worth £154.99
  • FREE system cleanse
  • Up to a 10-year guarantee
  • Flue worth up to £100
  • Fitting pack
  • All the right safety attachments

When you are comparing quotes for replacing your existing, remember to check if these things are included and don't forget is the quote includes VAT.

  • A Worcester Bosch boiler
  • Installation
  • Smart Thermostat
  • Worcester Bosch magnetic filter
  • System cleanse
  • 10-year guarantee
  • Flue
  • All the additional parts and required pipework
  • All the right safety attachments

If you would like to replace your boiler or just get a genuine fixed price, tap the button.