Types of Central Heating Boilers

By Rob Hull on July 23, 2010

The market today offers a wide range of types of central heating boilers of all shapes and sizes, from small and compact boilers that can fit in the space of a small kitchen cupboard to larger, high-output monoliths.

Each of the types of central heating boilers available have their own pros and cons, some vastly different, while others only seem to only change aesthetically. Boilers can run on gas, oil and even electricity, so it can be often confusing working out exactly what you need, and what you can really have!

What Boiler Type for What Purpose?

Depending on your requirements, there are a range of types of central heating boilers to consider, ranging in size, cost, output, storage and efficiency but whatever your need it’s imperative that you get professional advice and quotes before you proceed. These include:

Combination Boilers

The most popular boiler type on the market today, sales of combination boilers (often referred to as a ‘combi’ boiler) account for more than half of boilers sold within the UK. This is mainly due to its convenience, as most central heating systems will heat a copper cylinder located in an airing cupboard using a boiler to provide hot water, but a combination boiler will heat the water needed around the house for taps and such from within its unit, and is combined with a central heating system. A combi system will not require a cold water tank or separate water cylinder to supply it, which means that the costs of hot water will be a little lower than with a boiler that holds water in a cylinder. The only downside to the lack of water cylinder in a combi boiler is that the rate of hot water produced is likely to be lower than with a boiler with a water cylinder, even more so in the colder months.

Wall Mounted Boilers

Most boilers produced today are made to be wall mounted, with more compact and lighter heat exchangers created with materials including lightweight cast iron, stainless steel, copper or aluminium. Wall mounted boilers come in many versions, such as with a Fanned Flue or Room Sealed. As with most new boilers, the wall mounted type of boiler is required to have fitted a “system by-pass”, which is required to filter water throughout the boiler appliance to prevent the often loud noise that boilers are known to create, called “kettling”.

Free Standing Boilers

Usually created to be narrow enough to fit snugly between fitted kitchen units, these floor standing boilers can be installed in other suitable locations also.

Condensing Boilers

This type of boiler boasts an effective “heat exchanger”, which allows heat to be re-circulated rather than lost up the flue of the boiler, making it more energy efficient and therefore reducing fuel costs significantly for the owner. One of the issues often mentioned with condensing boilers is the pluming effect it creates from the flue terminal, which is often mistaken for steam. The pluming is due to droplets of water that are held in suspension throughout the boilers flue, and is not a danger, although is considered a nuisance and will occur for all the time that the boiler is running. Because of this, the placement of a condensing boiler can be more difficult.

Back Boilers

Old back boilers located in fireplace areas in homes must be replaced due to recently passed building regulations, and these are usually replaced by a high efficiency or a condensing boiler. Back boilers should not be sold in many cases because of the open flued model, unless it is much too complex or pricey to install a new boiler replacement. Back Boilers can only be fitted if they can fit the Seasonal Efficiency of Domestic Boilers rating in the UK, which is a minimum of 78% efficiency. Often people will choose to fill the space a back boiler leaves with a gas fire and a new condensing combination boiler elsewhere in the household.

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Servicing typically costs between £50-£80 so what are you waiting for?

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New & Replacement LPG Boilers

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Ballantrae KA26 - Current Boiler: Back boiler. 20 Years old. Located in the living, Not to too sure where it may need moving too. New Boiler: Open to advice on LPG\'s and Back boilers- and any advice that might help.Working. Radiators all ok. Replace ASAP. Contact Anytime. Appointment Anytime. Property is A Hotel.

New & Replacement Gas Boiler Installation (ECO grant funded)

TS6 - Current boiler: Back boiler: 15yrs plus. Benefits: childtaxcredit. earns: No one working. Call anytime
LU4 - Heatline S30 compact non condensing approx 12 yrs old. not working Benefits: childtaxcredit Earns less £15,860k pa. employmentsupport-under16,employmentsupport-disabledchildpremium Call ANYTIME.
CA2 - Current boiler is approx 10 years old, located in the living room, back boiler. Faults: no working as it should Benefits: childtaxcredit,workingtaxcredit-under16,workingtaxcredit-under20 House hold income is below £15,860. Contact: after six
Mellor BB2 - Current boiler: Worcester 28 CDI. 10yrs. All copper pipes. Located in a porch at the back of house w/m. Faults: inefficient. Benefits: working tax credit-disabled worker. Household income below £15,860. Call anytime.
SY11 - Current boiler: Back boiler, Glow worm. 15yrs plus. Benefits: pensioncredit. Call anytime
NE15 - Current boiler is approx 14 years old, back boiler located in the living room. Faults: takes 3 hours to get hot water. Benefits: childtaxcredit House hold income is below £15,860. Contact: 10am

New & Replacement Gas Boilers

Ystalyfera SA9 - Current Boiler: no boiler. Age: no boiler. Located: it was a back boiler. Looking to switch to a combi. Would like it preferably upstairs in the bedroom. Radiators: all ok. Would like the work to be done within 3 months. Contact: anytime. Appointments: anytime.
OX10 - in motions of buying it. Half way through, looking to go through in April May. Current boiler: Back boiler. 15yrs plus. Not sure if working. 2 bed mid terrace. Probably wants a combi. Call anytime. Replace within 3 months. Appointments: can have access. working hours
Resolven SA11 - Current boiler: 20yrs plus, old back boiler system and replace with a new combi boiler. Call anytime. replace 1 rad in replacement of back boiler. replace within 3 months. Appointments: anytime
PR9 - Current boiler: Back boiler. Does work. Change to combi. Call anytime before 10.30am or after 2.30pm. Replace within 3 months. Appointments: evenings best or weekends
BS15 - Current boiler is a back boiler - I would like to get a quote for a new boiler/ fire removed and tank removed Open to advice on make and model to be located same place as current boiler in the bedroom. We currently have a emersion heater in the bedroom cupboard, water tank in the loft. Preferably contact me 12-1 weekdays, evenings after 6pm or weekend. Thanks, ·····
LE3 - Current boiler: Baxi back boiler. 20yrs plus. Does work. Wants a new back boiler. Call anytime. Replace within 3 months. Appointments: anytime next week
KA8 - Current boiler: boiler has been removed. Thinks rads are ok but may need to replace 1-2. May have been a back boiler. Requires a combi. Replace within 3 months. Call anytime. Appointments: mornings.
TN23 - Current Boiler: Baxi back boiler. 25 Years old. Located in the front room, advice on moving. New Boiler: Open to advice. Working. Radiators all ok. Replace with in the month. Contact Anytime. Appointment Anytime.
NW2 - Current Boiler: Baxi Back boiler. 20 years old and workin. Located behind fire. Rads ok. Replace within 3 months. Contact anytime. Appointments anytime.

New & Replacement Gas Central Heating Systems

G13 - Current boiler is a back boiler, located in the living room. Open to advice of new boiler location and type. Radiators maybe required. Not working. Replace: within 3 months Contact: customer will be at the flat and available 20 - 23 January all day & 30/31 January all day. Contact: anytime after 8.30am -7pm

Repairs to Electric Boiler Systems

SE17 - I have an electrical boiler which is currently not producing any hot water. Model - OSO Hotwater Direct 20 RD

New Electric Boiler Installation

HP14 - To replace leaking back boiler connected to coal/wood burning stove
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