Worcester Greenspring CWi47 Technical And Speci?Cation Information page 9

What is a 'combi' boiler?
A 'combi' or combination boiler is a high efficiency water
heater and a central heating boiler combined (hence the
name) within one compact unit. Water is heated directly
from the mains eliminating the need for a hot water storage
cylinder and the associated cold water storage cistern in the
roof space. Because your hot water is delivered to your taps
or shower at mains pressure it's very convenient and can
save on your hot water costs. As an added benefit, showers
from a 'combi' can be comparable with the performance
of a power shower.
So a 'combi' can also give you a little extra room to play
with, making it ideal for a flat or a bungalow with very little
or no roof space and it's also the right choice if you want
to use your loft space for a room conversion. Another
'combi' benefit is that it can generally save you money on
installation time and costs as well installation materials.
'Combi' boilers are so popular that they account for two
out of every three new domestic boilers installed in Britain
every year.
What is a regular boiler?
Regular boilers – sometimes referred to as traditional or
conventional boilers – are suitable for homes that already
have a traditional heating and hot water system that requires
a separate hot water cylinder. Regular boilers also require a
cold water storage cistern to feed the hot water cylinder
and an expansion cistern in the loft. They are a good option
for any home where a large volume of stored hot water is
required e.g. homes with two or more bathrooms, or in
areas where the water pressure is low. Regular boilers are
compatible with solar water heating systems to bring you
the added benefits of environmentally friendly hot water
and further cost savings.
What is a system boiler?
Both a system boiler and a regular boiler work on the principle
of stored hot water – but a system boiler is different in two
important ways. Firstly, many of the components of the
heating and hot water system are built into the boiler itself,
making it quicker and easier to install. Secondly, it doesn't
need a feed and expansion cistern in the loft. There are two
kinds of cylinder which this type of system may have –
a mains pressure hot water cylinder or a low pressure hot
water cylinder. They are also compatible with solar water
heating systems to bring you the added benefits of
environmentally friendly hot water and reduced hot water
and heating costs.
Hot water to baths,
showers and basins
Worcester
combi boiler
with programmer
Kitchen and
appliances
Cold
mains
Combi boiler layout
Feed and
expansion
cistern
Cold water
storage cistern
Hot water to
baths, showers
and basins etc
Worcester
regular boiler
with programmer
Regular boiler layout and solar water heating system
Hot water cylinder
Hot water to
baths, showers
and basins etc
Worcester
system boiler
with programmer
Cold mains
System boiler layout and solar water heating system
(System boiler with unvented hot water cylinder)
Drawings are for illustrative purposes only.
Room
thermostat
Worcester Greenskies
solar thermal panels
Hot water cylinder
Room
thermostat
Worcester Greenskies
solar thermal panels
Room
thermostat
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