What are Combi boilers?
Combination boiler or
combi boilers come being one of the most common types of boilers used in UK for
a reason. Unlike the system and conventional units, the combination boilers are
designed to be an all in one unit which produces hot water for taps and central
heating in order to cut down the use of storage tanks or cylinders, thus
occupying the least space required to house the boiler. Additionally on a
comparison, the installations are much easier and faster than any other boiler
The combi boilers
operates by using the water from the main supply that results in stronger water
pressure and ensures that you would never be lacking on hot water again. The modern
highly efficient units come, being a stainless steel condensing boiler with an
inbuilt heat exchanger that operates in order to serve the customers with hot
There are two main
reasons behind the combi boilers great and powerful efficiency i.e. these units
have high operating efficiency and low internal water volume. This means when
in summer days you don’t need space heating you are only paying to heat water
which is domestically required.
Now that you have a
well knowledge about the combi boilers, you might be thinking about how to
bleed a central heating system combi boiler?
The infiltration in
your heating system can reduce the efficiency of your unit, turn your radiators
cold and produce abnormal sounds like whistling or humming, demanding an urge
to bleed your central heating system.
If you find your system
pressure to be too high then releasing some of the air out of the system would
likely solve the problem for you and put the pressure down to a required level.
In case of the combi
boilers, the hot water circulates between the radiator and the boiler through
pipes. Over the time, the air seeps into the pipes, creating air bubbles which
then interfere with the distribution of water in the pipe and the vessel, thus
reducing the efficiency level of your system and generating huge energy waste
which certainly increases your energy bills.
Bleeding the system
would, therefore, allow a good circulation of hot water in the pipe lines, and
would eventually result into uniform heat diffusion along with a cut down on
your energy bills.
Now that you have a
clear understanding of why bleeding comes being important for your system, let
us discuss about how to bleed a central heating system combi boiler?
How to bleed a central heating system Combi boiler?
The accumulated air in your boiler can be removed by
following these easy steps-
- Depending on the type of bleed valve in
your system, you need to undo it using a radiator bleed key or a flat
- Now put the boiler system off in order to
allow the air to rise to the top of the radiator and prevent it from
interfering during the process.
- Use a pair of grips to ensure that the
valves at the bottom of your radiator are open in order to allow the water to
flow into the radiator.
- Now loosen the radiator’s bleed valve
with a radiator key or a flathead screwdriver.
- As soon as you loosen the bleed valve,
you will be able to hear hissing sound of the air escaping.
- Once the water begins to come out, you
know that all the air has been released from the radiator. Now tighten the
bleed valve back.
- It is recommended to keep a cloth ready
for any droplets that would come out of the system as soon as the air escapes.
- Now go around each of the radiators in
the house, repeating the process if required.
Warning- It is highly
recommended to consider a professional help if you have no experience about it,
as it can be dangerous dealing with water flowing with a lot of pressure.