Conventional versus Combination Boilers - The Pros and Cons:
A Conventional boiler is purely a heating appliance – there will be an external hot water cylinder, control valves and radiators.
Worcester-Bosch Ri conventional boiler
Why would you want one?
- More than one hot water outlet can be supplied simultaneously (dependant on a separate storage cylinder)
- You desire a longer service life for a boiler than 10-12 years.
- You would prefer to have a stored hot/cold water supply in the house
- You may have recently invested in a new hot water cylinder/tanks
- You want an electrical immersion heater as hot water backup in case of boiler failure
- The water flow rate (sometimes erroneously described as pressure by plumbers) is too low for a combination boiler (but see low water mains pressure solutions as there are solutions available)
- All conventional boilers are now condensing technology, mandatory in the UK
- Perceived reliability advantage.
A System Boiler;
Is a conventional boiler (above) with the circulation pump mounted within the boiler casing, most of these are designed to be fitted to a sealed radiator system (in other words, one without a header tank).
They also incorporate some sealed system components, such as an expansion vessel, shown in the ATAG boiler below.
ATAG i32S System Boiler
A Combination boiler contains all the necessary controls and equipment to provide instantaneous hot water and also central heating – apart from radiators and pipe, everything else is in the boiler. There are now over 7 million households in the UK equipped with Combination boilers.
New for 2019, Worcester Bosch Greenstar 8000
Why would you want one?
- Convenience. Hot water is always available, 24 hours a day
- Economy. Only heat the hot water you use. Ideal if you are at home infrequently.
- Consecutive hot water demands can be made without running out
- You don’t require to run two hot water taps simultaneously
- No water tanks in the roof or hot water cylinders are required.
- It’s a one box compact solution, ideal for small properties
- All combination boilers are condensing versions, now mandatory in the UK
- It offers mains pressure showering without a pump (ideal for flats or loft conversions)
